The Dragon Archive - User contributions [en]

Fast Edit

2025-06-27T16:58:38Z

Polluks:

Fast Edit v1.00 was written by Geir Hovland in the period March-August 1990. After the review in [[Dragon Update]] by Raymond Roach in December 1990, version v1.01 was released. As of September 2011, FEdit is released to the public domain by the author.

FAST EDIT - REVIEWED BY RAYMOND ROACH, DRAGON UPDATE, DECEMBER 1990
-------------------------------------------------------------------
When I think that I have found the best text editor/word processor for the
Dragon, up comes someone with another which offers much that the others do not.
Geir Hovland has done just that with his FEDIT V1.00 disc. I have reviewed it
using my Dragon 64 with Superdos E6 and a Panasonic KX-P1081 printer.
The screen presentation is 64 x 32 upper and lower case characters. This, using
a TV set for the screen, is a little difficult to read at my age, but is really
very good, the program is fully menu driven and very straightforward to use.
The left/right arrow keys bring the required menus on screen. Only one hiccup
came to light in the edit mode. After making a deletion, the cursor did not
flash until the left arrow as pressed a second time. Once this was known, no
other problems were found. Block move, copy or delete functions are easy to use
as are the word search/replace facilities. A menu allows you to control key
repeat rate and delay time, and, if you like that sort of thing, have a
keyclick. There is also a menu which allows you to upload and download text
between computers at one of four Baud rates. The print menu provides for full
or part print with or without linefeed. It also caters for serial and parallel
printer connection.
Now I come to the part which I found sets this program apart from others. You
can use the full IBM international character set within the text by pressing
the CLEAR key followed by the ASCII number. These 255 possibilities have really
expanded the Dragon in a way I have never found before.
Geir Hovland deserves every encouragement Dragon owners can give him - so
PLEASE buy a copy of the disc, which brings a first rate English manual with
it, and open up the Dragon for even greater use.
P.S. Having just printed a proof copy of this review I realised that I have
forgotten another word of information. When you have finished your text, ALWAYS
end with an ENTER. If you do not, the last line will not print out - as I have
just reminded myself.
The disc can be obtained from G.E. Hovland, Stubbsvingen 67B, 7036 Trondheim,
Norway. Because of the high charges involved in international cheques, please
pay in Norwegian Kroner. The cost for disc and manual is only 100 Kroner. (Ask
your bank how you can pay).

Comment by the author: In the updated version V1.01, an extra return/linefeed
is sent to the printer after the last page. The cursor flash issue pointed out
has also been fixed.

Screenshots
-------------------------------------------------------------------

[[File:fedit-1.png]]

[[File:fedit-2.png]]

[[File:fedit-3.png]]

[[File:fedit-4.png]]

[[File:fedit-5.png]]

[[Category:Software]]

OS-9 Editor Assembler

2025-06-27T16:50:35Z

Polluks: Category

{| align="right" valign="top"
|{{Infobox Game
|Image = [[Image:OS9_Assembler.png|center|300px|Title screen]]
|Gamenumber =
|Company = [[Microware Systems Corporation]]
|Developer =
|Publisher = [[Dragon Data Ltd]]
|Musician =
|HVSC =
|Release = 1980
|Platform = [[Dragon 64]]
|Genre =
|Gamemode =
|Operation = {{Keyboard}}
|Media = {{Diskette}}
|Language = {{EN}}
|Info =
}}
|}

Editor, assembler and debugger for the OS-9 operating system.

==Packaging==

[[File:OS9_Assembler_diskette.jpg|300px|Assembler diskette]]

==Downloads==

[http://archive.worldofdragon.org/archive/index.php?dir=Disks/Dragon/&file=OS-9%20Editor%20Assembler%20Debugger%20%28198x%29%28Dragon%20Data%20Ltd%29%5B%21%5D.zip OS-9 Editor Assembler Debugger diskette] (Zipped VDK image)

[[Category:Software]] [[Category:OS-9]] [[Category:Programming]]

OS-9 C Compiler

2025-06-27T16:49:33Z

Polluks: Category

{| align="right" valign="top"
|{{Infobox Game
|Image = [[Image:CCompiler_DragonData_Screenshot01.png|center|300px|Title screen]]
|Gamenumber =
|Company = [[Microware Systems Corporation]]
|Developer =
|Publisher = [[Dragon Data Ltd]]
|Musician =
|HVSC =
|Release =
|Platform = [[Dragon 64]]
|Genre =
|Gamemode =
|Operation = {{Keyboard}}
|Media = {{Diskette}}
|Language = {{EN}}
|Info =
}}
|}

K&R style C compiler for the OS-9 Operating System.

==Packaging==

The OS-9 C Compiler was delivered on two diskettes.

[[File:CCompiler_DragonData_Inlay.jpg|600px]] 
[[File:OS9_C_Compiler_diskette_1.jpg|300px|C Compiler diskette 1]][[File:OS9_C_Compiler_diskette_2.jpg|300px|C Compiler diskette 2]] 
[[File:C-Compiler-OS9-Disk-label-cleaned-Disk-1of2.jpg|300px]][[File:C-Compiler-OS9-Disk-label-cleaned-Disk-2of2.jpg|300px]] 
[[File:CCompiler_DragonData_Sheet01.jpg|300px]][[File:CCompiler_DragonData_Sheet02.jpg|300px]]

==Downloads==

[http://archive.worldofdragon.org/archive/index.php?dir=Disks/Dragon/&file=Dragon%20Data%20Ltd%20-%20OS-9%20C.zip OS-9 C Compiler v1.1] (Zipped VDK images)

[http://archive.worldofdragon.org/archive/index.php?dir=Manuals/&file=Dragon%20Data%20Ltd%20-%20OS9%20-%20C%20Compiler.zip OS-9 C Compiler v1.1 User's Guide] (Zipped PDF document)

[[Media:C-Compiler-OS9-Manual-Dragon_Data.pdf|OS-9 C Compiler v1.1 User's Guide (A different version)]] (PDF file)

[[Media:C-Compiler-OS9-Quick-Ref.pdf|OS-9 C Compiler Quick Reference Card]] (PDF file)

[[Category:Software]] [[Category:OS-9]] [[Category:Programming]]

OS-9 Basic 09

2025-06-27T16:48:47Z

Polluks: Category

{| align="right" valign="top"
|{{Infobox Game
|Image = [[Image:Basic09.png|center|300px|Title screen]]
|Gamenumber =
|Company = [[Microware Systems Corporation]]
|Developer =
|Publisher = [[Dragon Data Ltd]]
|Musician =
|HVSC =
|Release =
|Platform = [[Dragon 64]]
|Genre =
|Gamemode =
|Operation = {{Keyboard}}
|Media = {{Diskette}}
|Language = {{EN}}
|Info =
}}
|}

BASIC09 is the BASIC interpreter/compiler for OS-9. This is a very structured version of BASIC, quite different from the Microsoft BASIC that is part of the DRAGON ROM.

== Screenshots ==

[[File:Basic09_Screenshot01.png|300px]][[File:Basic09_Screenshot02.png|300px]]

==Packaging==

[[File:Basic09_Inlay.jpg|300px]] 
[[File:Basic09_Disk.jpg|300px]]

==Downloads==

[http://archive.worldofdragon.org/archive/index.php?dir=Disks/Dragon/&file=Dragon%20Data%20Ltd%20-%20OS-9%20BASIC09.zip OS-9 BASIC09 diskette] (Zipped VDK image)

[http://archive.worldofdragon.org/archive/index.php?dir=Manuals/&file=Dragon%20Data%20Ltd%20-%20OS9%20-%20Basic09.zip OS-9 BASIC09 User's Guide] (Zipped PDF document)

[[Category:Software]] [[Category:OS-9]] [[Category:Programming]]

Tele-Forth

2025-06-27T16:48:01Z

Polluks: Category

{| align="right" valign="top"
|{{Infobox Game
|Image = [[Image:TeleForth_Screenshot01.png|center|300px|Titleimage from the game]]
|Gamenumber =
|Company = [[Armadillo International Software]]
|Developer =
|Publisher = [[Microdeal]]
|Musician =
|HVSC =
|Release = [[:Category:Game_1983|1983]]
|Platform = [[Dragon 32]] or [[Dragon 64]]
|Genre = [[:Category:Application|Application]]
|Gamemode =
|Operation = {{Keyboard}}
|Media = {{Cassette}}
|Language = {{EN}}
|Info =
}}
|}

== Screenshots ==

[[File:TeleForth_Screenshot02.png|300px]]

== Packaging ==
[[File:TeleForth_Binder.jpg|600px]] 
[[File:TeleForth_Tape.jpg|300px]]

== Download ==

* [http://archive.worldofdragon.org/archive/index.php?dir=Tapes/Dragon/cas/&file=Tele-Forth%20%281983%29%28Microdeal%29%5B%21%5D.zip Tele-Forth] (zipped .CAS file)

[[Category:Application]] [[Category:Game_In_Archive]] [[Category:Game_1983]] [[Category:Game_Online]] [[Category:Programming]]

OS-9 Pascal

2025-06-27T16:46:00Z

Polluks: Category

{| align="right" valign="top"
|{{Infobox Game
|Image = [[Image:OS9Pascal_Screenshot01.png|center|300px|Title screen]]
|Gamenumber =
|Company = [[Microware Systems Corporation]]
|Developer =
|Publisher = [[Dragon Data Ltd]]
|Musician =
|HVSC =
|Release =
|Platform = [[Dragon 64]]
|Genre =
|Gamemode =
|Operation = {{Keyboard}}
|Media = {{Diskette}}
|Language = {{EN}}
|Info =
}}
|}

A Pascal editor and compiler for the OS-9 operating system.

Scans courtesy of Richard Harding.

== Screenshots ==

== Packaging ==

[[File:OS9Pascal_Inlay_th.jpg|602px|link=https://archive.worldofdragon.org/images/e/ed/OS9Pascal_Inlay.jpg]] 
 
[[File:OS9Pascal-disk-1of2.jpg|300px]] [[File:OS9Pascal-disk-2of2.jpg|302px]] 
 
[[File:Pascal-OS9-label-1of2.jpg|300px]] [[File:Pascal-OS9-label-2of2.jpg|300px]]

==Downloads==

* [http://archive.worldofdragon.org/browse/?dir=downloads/Software/Dragon/Dragon%20Data%20Ltd/OS-9/Pascal OS-9 Pascal]

[[Category:Software]] [[Category:OS-9]] [[Category:Programming]]

Vbcc

2025-06-27T16:45:05Z

Polluks: Category

The '''vbcc''' cross compiler and its '''vlink''' linker support [[Dragon DOS]], the assembler is called '''vasm6809_mot'''.

http://www.compilers.de/vbcc.html
http://sun.hasenbraten.de/vlink/

[[Category:Software]] [[Category:Programming]]

Dragon DOS

2025-06-27T16:42:28Z

Polluks: Subcategory

== Dragon DOS 1.x ==

[[Dragon Data Ltd]] comissioned [[The Micro Works]] to write the original Dragon DOS, some pre-release examples of this including the (c) Micro Works signature can be found in the downloads area. Shortly after release a number of bugs were discovered in 1.0 and a number of articles were published in [[Dragon User]] with patches to the ROM code to correct the worst of these. The most common version is 1.0, it is not known if any other version was officially released although 1.7 has been seen but the source of 1.7 and the differences with 1.0 are unknown at this time.

== Dragon DOS 2.x ==

For the [[Dragon Alpha]] a modified version of Dragon DOS was required, one that would load into RAM from disk rather than exist on a ROM. [[Vivaway Ltd]] were given the source code for Dragon DOS 1.x and Dragon DOS 2.x was created. A VDK disk image of Dragon DOS V2.F for the [[Dragon Alpha]] can be found in the downloads area. From looking at segments of the original Dragon DOS 2.C source code it would appear that [[Vivaway Ltd]] implemented the changes as options so that the source code could be assembled for a Dragon ROM or RAM implementation - There is also an option that appears to infer it would also assemble to work on a Tandy CoCo.

== Dragon DOS 4.x ==

Eurohard wanted to release an updated Dragon DOS for the [[Dragon 64]] / [[Dragon 200]] that contained all the known bugfixes and to avoid confusion with the 2.x series numbering they jumped straight to V4.0. A ROM image of this is available for download.

== Dragon DOS Interface Pictures ==

<gallery caption="Dragon DOS Interface">
Image:DiskController_Box.jpg|Box
Image:DiskController_Top.jpg|Casing Top
Image:DiskController_Bottom.jpg|Casing Bottom
Image:DiskController_PCB_Top.jpg|Issue 1 PCB Top
Image:DiskController_PCB_Bottom.jpg|Issue 1 PCB Bottom
Image:DiskController_Issue2_PCB_Top.jpg|Issue2 PCB Top
</gallery>

== Dragon DOS IC Parts List ==

'''DragonDOS Board IC list (with Datasheets)
{|{{PrettyTable|width: 700px; font-size: 2em;}}
|''Part Number''||''Description''||''Datasheet''
|-
| 2764 || 8Kb EPROM || [[Media:HN482764G.pdf|(pdf)]]
|-
| SN7416N || Hex inverter buffers/drivers with open-collector high-voltage outputs || [[Media:SN5406-SN5416-SN7406-SN7416.pdf|(pdf)]]
|-
| SN7417N || Hex buffers/drivers with open-collector high-voltage outputs || [[Media:SN5407-SN5417-SN7407-SN7417.pdf|(pdf)]]
|-
| SN74LS00N || Quad 2-input positive-NAND gates || [[Media:SN5400-SN54LS00-SN54S00-SN7400-SN74LS00-SN74S00.pdf|(pdf)]]
|-
| SN74LS04N || Hex inverters || [[Media:SN5404-SN54LS04-SN54S04-SN7404-SN74LS04-SN74S04.pdf|(pdf)]]
|-
| SN74LS74AN || DUAL D-TYPE POSITIVE EDGE-TRIGGERED FLIP-FLOPS WITH PRESET AND CLEAR || [[Media:SN54-74LS74N.pdf|(pdf)]]
|-
| SN74LS139N || DUAL 1-OF-4 DECODER/DEMULTIPLEXER || [[Media:SN54-74LS139.pdf|(pdf)]]
|-
| SN74LS174N || Hex/Quadruple D-Type Flip-Flops With Clear || [[Media:SN54174-SN54175-SN54LS174-SN54LS175-SN54S174-SN54S175-SN74174-SN74175-SN74LS174-SN74LS175-SN74S174-SN74S175.pdf|(pdf)]]
|-
| WD2797PL-02 || Floppy Disk Formatter/Controller || [[Media:WD279x-02.pdf|(pdf)]]
|-
|}
 

== New developments ==

Several people have created new versions of the DragonDOS controller, which use the same WD2797 floppy controller IC as the original controller but are smaller.

* Jose Leandro's Disk Controller (2012) Eagle Schematics:[[File:DragonDos_Controller_-_Jos%C3%A9_Leandro.zip]]
This one was created by Jose Leandro, a spanish Dragon user.

Full details (in spanish): http://hardware.speccy.org/temp/Dragon-1.html

<gallery caption="Jose Leandro's Dragon Disk Controller">
Image:DragonDOS_JoseLeandro_PCB_Top.jpg|PCB Top
Image:DragonDOS_JoseLeandro_PCB_Bottom.jpg|PCB Bottom
</gallery>
 

* Lafumat's Dragon Disk Controller (July 2012)

This one was created by Lafumat, a user of the spanish RetroWiki and Zona de Pruebas forums.

<gallery caption="Lafumat's Dragon Disk Controller">
Image:Lafumat_Disk_Controller-V1.1-PCB_Top.jpg|PCB Top
Image:Lafumat_Disk_Controller-V1.1-PCB_Bottom.jpg|PCB Bottom
</gallery>

== Dragon DOS Downloads ==
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Dragon%20Data%20Ltd%20-%20Dragon%20DOS%201.0%20-%20Pre-Release%201.zip Dragon DOS 1.0 - Pre-Release 1] (Zipped ROM file)
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Dragon%20Data%20Ltd%20-%20Dragon%20DOS%201.0%20-%20Pre-Release%202.zip Dragon DOS 1.0 - Pre-Release 2] (Zipped ROM file)
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Dragon%20Data%20Ltd%20-%20Dragon%20DOS%201.0%20-%20Pre-Release%201.zip Dragon DOS 1.0 - Pre-Release 3] (Zipped ROM file)
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Dragon%20Data%20Ltd%20-%20Dragon%20DOS%201.0.zip Dragon DOS 1.0] (Zipped ROM File)
* [http://archive.worldofdragon.org/archive/index.php?dir=Disks/Dragon/&file=Dragon%20Data%20Ltd%20-%20Dragon%20Alpha%28Professional%29%20-%20DragonDos%202.F%20Boot.zip Dragon DOS 2.F] (Zipped Disk Image)
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Eurohard%20S.A.%20-%20Dragon%20DOS%204.0.zip Dragon DOS 4.0 (English)] (Zipped ROM File)
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Eurohard%20S.A.%20-%20Dragon%20DOS%204.0%20%28ES%29.zip Dragon DOS 4.0 (Spanish)] (Zipped ROM File)
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Eurohard%20S.A.%20-%20Dragon%20DOS%204.1.zip Dragon DOS 4.1] (Zipped ROM file)

[[Category:System Software]]

Category:System Software

2025-06-27T16:41:13Z

Polluks: Category

[[Category:Software]]

RS-DOS

2025-03-03T20:12:57Z

Polluks:

'''RS-DOS''' ('''R'''adio '''S'''hack '''D'''isk '''O'''perating '''S'''ystem) was the primary disk operating system for the [[Tandy]]/[[Radio Shack]] TRS-80 Color Computer series, commonly referred to as the CoCo. It was developed by [[Tandy Corporation]] and was based on [[Microsoft]]'s [[BASIC]] interpreter with additional disk I/O functionality.

== Overview ==
RS-DOS was the standard disk operating system for early TRS-80 Color Computers before being largely replaced by third-party alternatives such as [[OS-9]] and [[Dragon DOS]]. Unlike [[MS-DOS]], RS-DOS was not a standalone operating system but rather an extension of the built-in [[Color BASIC]], adding disk commands and file management features.

== Features ==
* Provided basic file management capabilities, including [[LOAD]], [[SAVE]], [[RUN]], and [[DIR]] commands.
* Used a proprietary [[Disk File System]] that differed from common FAT-based file systems.
* Supported up to 35 tracks per disk and single-sided, single-density [[floppy disks]].
* Required the Color Computer Disk Extended BASIC ROM for operation.
* Lacked multitasking or advanced memory management features.

== Limitations ==
RS-DOS had several limitations:
* It did not support subdirectories or hierarchical file structures.
* Disk access was relatively slow compared to later systems.
* It lacked built-in support for hard drives or non-floppy disk storage.

== Successors ==
As computing demands increased, RS-DOS was gradually replaced by more powerful operating systems such as [[OS-9 Level 1]] and [[OS-9 Level 2]], which provided multitasking and a Unix-like environment. Other third-party DOS implementations, such as [[Disk Extended Color BASIC]] and [[Dragon DOS]], also emerged to expand the capabilities of the TRS-80 Color Computer.

== See Also ==
* [[TRS-80 Color Computer]]
* [[Color BASIC]]
* [[OS-9 System]]
* [[Dragon DOS]]

[[Category:System Software]]

RS-DOS

2025-03-03T20:11:25Z

Polluks: Created page with "'''RS-DOS''' ('''R'''adio '''S'''hack '''D'''isk '''O'''perating '''S'''ystem) was the primary disk operating system for the Tandy/Radio Shack TRS-80 Color Computer se..."

'''RS-DOS''' ('''R'''adio '''S'''hack '''D'''isk '''O'''perating '''S'''ystem) was the primary disk operating system for the [[Tandy]]/[[Radio Shack]] TRS-80 Color Computer series, commonly referred to as the CoCo. It was developed by [[Tandy Corporation]] and was based on [[Microsoft]]'s [[BASIC]] interpreter with additional disk I/O functionality.

== Overview ==
RS-DOS was the standard disk operating system for early TRS-80 Color Computers before being largely replaced by third-party alternatives such as [[OS-9]] and [[DragonDOS]]. Unlike [[MS-DOS]], RS-DOS was not a standalone operating system but rather an extension of the built-in [[Color BASIC]], adding disk commands and file management features.

== Features ==
* Provided basic file management capabilities, including [[LOAD]], [[SAVE]], [[RUN]], and [[DIR]] commands.
* Used a proprietary [[Disk File System]] that differed from common FAT-based file systems.
* Supported up to 35 tracks per disk and single-sided, single-density [[floppy disks]].
* Required the Color Computer Disk Extended BASIC ROM for operation.
* Lacked multitasking or advanced memory management features.

== Limitations ==
RS-DOS had several limitations:
* It did not support subdirectories or hierarchical file structures.
* Disk access was relatively slow compared to later systems.
* It lacked built-in support for hard drives or non-floppy disk storage.

== Successors ==
As computing demands increased, RS-DOS was gradually replaced by more powerful operating systems such as [[OS-9 Level 1]] and [[OS-9 Level 2]], which provided multitasking and a Unix-like environment. Other third-party DOS implementations, such as [[Disk Extended Color BASIC]] and [[DragonDOS]], also emerged to expand the capabilities of the TRS-80 Color Computer.

== See Also ==
* [[TRS-80 Color Computer]]
* [[Color BASIC]]
* [[OS-9 System]]
* [[DragonDOS]]

[[Category:System Software]]

Delta DOS

2025-03-03T19:58:14Z

Polluks: Category

== Description ==
The Delta DOS interface is a disk controller cartridge with disk access functions for BASIC in ROM. It was made by [[Premier Microsystems]] and there are two known versions of the interface. 

== Delta DOS Interface Pictures ==
<gallery caption="Casing">
Image:DeltaDos_Top.jpg|Casing Top
Image:DeltaDos_Bottom.jpg|Casing Bottom
</gallery>
 
<gallery caption="Mk 1 Board (WD1771)">
Image:DeltaDos_PCB_Top.jpg|Mk1 PCB Top
Image:DeltaDos_PCB_Bottom.jpg|Mk1 PCB Bottom
</gallery>
 
<gallery caption="Mk 2 Board (WD2791)">
Image:Delta-mk2-top.JPG|Mk2 PCB Top
Image:Delta-mk2-bottom.JPG|Mk2 PCB Bottom
</gallery>
 

== IC Parts Lists ==
'''Mk1 Board IC list (with Datasheets)
{|{{PrettyTable|width: 700px; font-size: 2em;}}
|''Part Number''||''Description''||''Datasheet''
|-
| 2764 || 8Kb EPROM || [[Media:HN482764G.pdf|(pdf)]]
|-
| INS1771N-1 || WD1771 compatible FDC controller || [[Media:INS1771N-1.pdf|(pdf)]]
|-
| ICL7660CPA || CMOS Voltage converter || [[Media:ICL7660.pdf|(pdf)]]
|-
| SN7404N || Hex inverters || [[Media:SN5404-SN54LS04-SN54S04-SN7404-SN74LS04-SN74S04.pdf|(pdf)]]
|-
| SN7416N || Hex inverter buffers/drivers with open-collector high-voltage outputs || [[Media:SN5406-SN5416-SN7406-SN7416.pdf|(pdf)]]
|-
| SN7417N || Hex buffers/drivers with open-collector high-voltage outputs || [[Media:SN5407-SN5417-SN7407-SN7417.pdf|(pdf)]]
|-
| SN74LS03N || Quad 2-input positive-NAND gates with open collector outputs || [[Media:SN5403-SN54LS03-SN5403-SN7403-SN74LS03-SN74S03.pdf|(pdf)]]
|-
| SN74LS04N || Hex inverters || [[Media:SN5404-SN54LS04-SN54S04-SN7404-SN74LS04-SN74S04.pdf|(pdf)]]
|-
| SN74LS08N || Quadruple 2-Input Positive-AND Gates || [[Media:SN5408-SN54LS08-SN54S08-SN7408-SN74LS08-SN74S08.pdf|(pdf)]]
|-
| SN74LS17N || Hex Buffers/Drivers With Open-Collector High-Voltage Outputs || [[Media:SN54LS07-SN74LS07-SN74LS17.pdf|(pdf)]]
|-
| SN74LS32N || Quad 2-input positive-OR gates || [[Media:SN5432-SN54LS32-SN54S32-SN7432-SN74LS32-SN74S32.pdf|(pdf)]]
|-
| SN74LS93N || 4-Bit Binary Counters || [[Media:SN5490A-SN5492A-SN5493A-SN54LS90-SN54LS92-SN54LS93-SN7490A-SN7492A-SN7493A-SN74LS90-SN74LS92-SN74LS93.pdf|(pdf)]]
|-
| SN74LS123N || Dual retriggerable monostable multivibrators || [[Media:SN54122-SN54123-SN54130-SN54LS122-SN54LS123-SN74122-SN74123-SN74130-SN74LS122-SN74LS123.pdf|(pdf)]]
|-
| SN74LS139AN || Dual 2-line to 4-line decoders / demultiplexers || [[Media:SN54LS139A-SN54S139-SN74LS139A-SN74S139A.pdf|(pdf)]]
|-
| SN74LS245N || Octal bus transceivers || [[Media:SN54LS245-SN74LS245.pdf|(pdf)]]
|-
|}
 
'''Mk2 Board IC list (with Datasheets)
{|{{PrettyTable|width: 700px; font-size: 2em;}}
|''Part Number''||''Description''||''Datasheet''
|-
| 2764 || 8Kb EPROM || [[Media:HN482764G.pdf|(pdf)]]
|-
| SN74LS00N || Quad 2-input positive-NAND gates || [[Media:SN5400-SN54LS00-SN54S00-SN7400-SN74LS00-SN74S00.pdf|(pdf)]]
|-
| SN74LS04N || Hex inverters || [[Media:SN5404-SN54LS04-SN54S04-SN7404-SN74LS04-SN74S04.pdf|(pdf)]]
|-
| SN74LS08N || Quadruple 2-Input Positive-AND Gates || [[Media:SN5408-SN54LS08-SN54S08-SN7408-SN74LS08-SN74S08.pdf|(pdf)]]
|-
| SN74LS32N || Quad 2-input positive-OR gates || [[Media:SN5432-SN54LS32-SN54S32-SN7432-SN74LS32-SN74S32.pdf|(pdf)]]
|-
| SN74LS123N || Dual retriggerable monostable multivibrators || [[Media:SN54122-SN54123-SN54130-SN54LS122-SN54LS123-SN74122-SN74123-SN74130-SN74LS122-SN74LS123.pdf|(pdf)]]
|-
| SN74LS139AN || Dual 2-line to 4-line decoders / demultiplexers || [[Media:SN54LS139A-SN54S139-SN74LS139A-SN74S139A.pdf|(pdf)]]
|-
| SN74LS174N || Hex/Quadruple D-Type Flip-Flops With Clear || [[Media:SN54174-SN54175-SN54LS174-SN54LS175-SN54S174-SN54S175-SN74174-SN74175-SN74LS174-SN74LS175-SN74S174-SN74S175.pdf|(pdf)]]
|-
| SN74LS240N || Octal buffers and line drivers, with 3-State outputs || [[Media:SN54LS240-SN54LS241-SN54LS244-SN54S240-SN54S241-SN54S244-SN74LS240-SN74LS241-SN74LS244-SN74S240-SN74S241-SN74S244.pdf|(pdf)]]
|-
| SN74LS245N || Octal bus transceivers || [[Media:SN54LS245-SN74LS245.pdf|(pdf)]]
|-
| ULN2003AN || HIGH-VOLTAGE, HIGH-CURRENT DARLINGTON TRANSISTOR ARRAYS || [[Media:ULN2002A-ULN2003A-ULN2003AI-ULN2004A-ULQ2003A-ULQ2004A.pdf|(pdf)]]
|-
| WD2791PL-02 || Floppy Disk Formatter/Controller || [[Media:WD279x-02.pdf|(pdf)]]
|-
|}
 

== Delta DOS ROM ==
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Premier%20Micros%20-%20DeltaDOS.zip Delta DOS ROM]
[[Category:Hardware]][[Category:System Software]][[Category:Peripherals]]

OS-9 System

2025-03-02T22:39:51Z

Polluks: Category

{| align="right" valign="top"
|{{Infobox Game
|Image = [[Image:OS9.png|center|300px|OS-9 promt]]
|Gamenumber =
|Company = [[Microware Systems Corporation]]/[[Eurohard SA]]
|Developer =
|Publisher = [[Dragon Data Ltd]]
|Musician =
|HVSC =
|Release =
|Platform = [[Dragon 64]]
|Genre =
|Gamemode =
|Operation = {{Keyboard}}
|Media = [[Image:Icon_disk525.png|26px]]
|Language = {{EN}}
|Info =
}}
|}

OS-9 is a real-time, multi-tasking and multi-user operating system for the Dragon 64.

==Downloads==

* [http://archive.worldofdragon.org/archive/index.php?dir=Disks/Dragon/&file=Dragon%20Data%20Ltd%20-%20OS-9%20System.zip OS-9 Level 1 V1.2 Operating System Diskette] (Zipped VDK image)

* [http://archive.worldofdragon.org/archive/index.php?dir=Disks/Dragon/&file=Eurohard%20SA%20-%20OS-9%20Level%201%20V2.0.zip OS-9 Level 1 V2.0 Operating System Diskette] (Zipped VDK image)

* [http://archive.worldofdragon.org/archive/index.php?dir=Manuals/&file=Dragon%20Data%20Ltd%20-%20OS9%20-%20System%20Guide.zip OS-9 Operating System User's Guide] (Zipped PDF document)

[[Category:Software]][[Category:System Software]][[Category:OS-9]]

File:Polluks.jpg

2025-03-02T22:30:53Z

Polluks:

User:Polluks

2025-03-02T22:28:45Z

Polluks: Polluks.jpg

[[File:Polluks.jpg|right]]
https://sites.google.com/site/tandycocoloco/wordpak-rs
http://www.colorcomputerarchive.com/coco/Documents/Manuals/Hardware/Wordpak%20Users%20Manual%20(PBJ%20Inc).pdf

http://users.axess.com/twilight/sock/rs232.html
http://www.cocopedia.com/wiki/index.php/Deluxe_RS232_Pak

http://dragon32.info/info/romref.html [[CoCo ROM Equivalents]]

https://www.everygamegoing.com/litem/The-Hitchhikers-Guide-To-The-Galaxy/107786/ http://www.retrowiki.es/viewtopic.php?t=200033991

https://github.com/prime6809/DragonRom https://github.com/prime6809/DragonDOS

== Cross ==
https://bitbucket.org/magli143/exomizer/wiki/Home

http://www.lwtools.ca

Vbcc

2021-10-22T20:15:15Z

Polluks: vasm6809_mot

Dragon DOS

2021-10-22T11:02:50Z

Polluks: /* New developments */ typo

== Dragon DOS 1.x ==

[[Dragon Data Ltd]] comissioned [[The Micro Works]] to write the original Dragon DOS, some pre-release examples of this including the (c) Micro Works signature can be found in the downloads area. Shortly after release a number of bugs were discovered in 1.0 and a number of articles were published in [[Dragon User]] with patches to the ROM code to correct the worst of these. The most common version is 1.0, it is not known if any other version was officially released although 1.7 has been seen but the source of 1.7 and the differences with 1.0 are unknown at this time.

== Dragon DOS 2.x ==

For the [[Dragon Alpha]] a modified version of Dragon DOS was required, one that would load into RAM from disk rather than exist on a ROM. [[Vivaway Ltd]] were given the source code for Dragon DOS 1.x and Dragon DOS 2.x was created. A VDK disk image of Dragon DOS V2.F for the [[Dragon Alpha]] can be found in the downloads area. From looking at segments of the original Dragon DOS 2.C source code it would appear that [[Vivaway Ltd]] implemented the changes as options so that the source code could be assembled for a Dragon ROM or RAM implementation - There is also an option that appears to infer it would also assemble to work on a Tandy CoCo.

== Dragon DOS 4.x ==

Eurohard wanted to release an updated Dragon DOS for the [[Dragon 64]] / [[Dragon 200]] that contained all the known bugfixes and to avoid confusion with the 2.x series numbering they jumped straight to V4.0. A ROM image of this is available for download.

== Dragon DOS Interface Pictures ==

<gallery caption="Dragon DOS Interface">
Image:DiskController_Box.jpg|Box
Image:DiskController_Top.jpg|Casing Top
Image:DiskController_Bottom.jpg|Casing Bottom
Image:DiskController_PCB_Top.jpg|PCB Top
Image:DiskController_PCB_Bottom.jpg| PCB Bottom
</gallery>

== Dragon DOS IC Parts List ==

'''DragonDOS Board IC list (with Datasheets)
{|{{PrettyTable|width: 700px; font-size: 2em;}}
|''Part Number''||''Description''||''Datasheet''
|-
| 2764 || 8Kb EPROM || [[Media:HN482764G.pdf|(pdf)]]
|-
| SN7416N || Hex inverter buffers/drivers with open-collector high-voltage outputs || [[Media:SN5406-SN5416-SN7406-SN7416.pdf|(pdf)]]
|-
| SN7417N || Hex buffers/drivers with open-collector high-voltage outputs || [[Media:SN5407-SN5417-SN7407-SN7417.pdf|(pdf)]]
|-
| SN74LS00N || Quad 2-input positive-NAND gates || [[Media:SN5400-SN54LS00-SN54S00-SN7400-SN74LS00-SN74S00.pdf|(pdf)]]
|-
| SN74LS04N || Hex inverters || [[Media:SN5404-SN54LS04-SN54S04-SN7404-SN74LS04-SN74S04.pdf|(pdf)]]
|-
| SN74LS74AN || DUAL D-TYPE POSITIVE EDGE-TRIGGERED FLIP-FLOPS WITH PRESET AND CLEAR || [[Media:SN54-74LS74N.pdf|(pdf)]]
|-
| SN74LS139N || DUAL 1-OF-4 DECODER/DEMULTIPLEXER || [[Media:SN54-74LS139.pdf|(pdf)]]
|-
| SN74LS174N || Hex/Quadruple D-Type Flip-Flops With Clear || [[Media:SN54174-SN54175-SN54LS174-SN54LS175-SN54S174-SN54S175-SN74174-SN74175-SN74LS174-SN74LS175-SN74S174-SN74S175.pdf|(pdf)]]
|-
| WD2797PL-02 || Floppy Disk Formatter/Controller || [[Media:WD279x-02.pdf|(pdf)]]
|-
|}
 

== New developments ==

Several people have created new versions of the DragonDOS controller, which use the same WD2797 floppy controller IC as the original controller but are smaller.

* Jose Leandro's Disk Controller (2012) Eagle Schematics:[[File:DragonDos_Controller_-_Jos%C3%A9_Leandro.zip]]
This one was created by Jose Leandro, a spanish Dragon user.

Full details (in spanish): http://hardware.speccy.org/temp/Dragon-1.html

<gallery caption="Jose Leandro's Dragon Disk Controller">
Image:DragonDOS_JoseLeandro_PCB_Top.jpg|PCB Top
Image:DragonDOS_JoseLeandro_PCB_Bottom.jpg|PCB Bottom
</gallery>
 

* Lafumat's Dragon Disk Controller (July 2012)

This one was created by Lafumat, a user of the spanish RetroWiki and Zona de Pruebas forums.

<gallery caption="Lafumat's Dragon Disk Controller">
Image:Lafumat_Disk_Controller-V1.1-PCB_Top.jpg|PCB Top
Image:Lafumat_Disk_Controller-V1.1-PCB_Bottom.jpg|PCB Bottom
</gallery>

== Dragon DOS Downloads ==
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Dragon%20Data%20Ltd%20-%20Dragon%20DOS%201.0%20-%20Pre-Release%201.zip Dragon DOS 1.0 - Pre-Release 1] (Zipped ROM file)
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Dragon%20Data%20Ltd%20-%20Dragon%20DOS%201.0%20-%20Pre-Release%202.zip Dragon DOS 1.0 - Pre-Release 2] (Zipped ROM file)
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Dragon%20Data%20Ltd%20-%20Dragon%20DOS%201.0%20-%20Pre-Release%201.zip Dragon DOS 1.0 - Pre-Release 3] (Zipped ROM file)
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Dragon%20Data%20Ltd%20-%20Dragon%20DOS%201.0.zip Dragon DOS 1.0] (Zipped ROM File)
* [http://archive.worldofdragon.org/archive/index.php?dir=Disks/Dragon/&file=Dragon%20Data%20Ltd%20-%20Dragon%20Alpha%28Professional%29%20-%20DragonDos%202.F%20Boot.zip Dragon DOS 2.F] (Zipped Disk Image)
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Eurohard%20S.A.%20-%20Dragon%20DOS%204.0.zip Dragon DOS 4.0 (English)] (Zipped ROM File)
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Eurohard%20S.A.%20-%20Dragon%20DOS%204.0%20%28ES%29.zip Dragon DOS 4.0 (Spanish)] (Zipped ROM File)
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Eurohard%20S.A.%20-%20Dragon%20DOS%204.1.zip Dragon DOS 4.1] (Zipped ROM file)

[[Category:Software]][[Category:System Software]]

User:Polluks

2021-10-13T07:16:41Z

Polluks: Cross

https://sites.google.com/site/tandycocoloco/wordpak-rs
http://www.colorcomputerarchive.com/coco/Documents/Manuals/Hardware/Wordpak%20Users%20Manual%20(PBJ%20Inc).pdf

http://users.axess.com/twilight/sock/rs232.html
http://www.cocopedia.com/wiki/index.php/Deluxe_RS232_Pak

http://dragon32.info/info/romref.html [[CoCo ROM Equivalents]]

https://www.everygamegoing.com/litem/The-Hitchhikers-Guide-To-The-Galaxy/107786/ http://www.retrowiki.es/viewtopic.php?t=200033991

https://github.com/prime6809/DragonRom https://github.com/prime6809/DragonDOS

== Cross ==
https://bitbucket.org/magli143/exomizer/wiki/Home

http://www.lwtools.ca

RED ROM DATA

2021-10-12T15:45:42Z

Polluks: fixed

#REDIRECT [[Red Rom Data]]

User:Polluks

2021-10-12T15:44:49Z

Polluks: ROM's

https://sites.google.com/site/tandycocoloco/wordpak-rs
http://www.colorcomputerarchive.com/coco/Documents/Manuals/Hardware/Wordpak%20Users%20Manual%20(PBJ%20Inc).pdf

http://users.axess.com/twilight/sock/rs232.html
http://www.cocopedia.com/wiki/index.php/Deluxe_RS232_Pak

https://bitbucket.org/magli143/exomizer/wiki/Home

http://dragon32.info/info/romref.html [[CoCo ROM Equivalents]]

https://www.everygamegoing.com/litem/The-Hitchhikers-Guide-To-The-Galaxy/107786/ http://www.retrowiki.es/viewtopic.php?t=200033991

https://github.com/prime6809/DragonRom https://github.com/prime6809/DragonDOS

Cumana Disk Drives

2021-10-12T15:40:29Z

Polluks:

Cumana marketed a range of 40 and 80 track disk drives for the Dragon with a disk interface provided by Premier Microsystems. Cumana DOS was simply [[Delta DOS]] by another name.

== Single drive unit ==
<gallery>
Image:Cumana_DiskDrive_Top.jpg
Image:Cumana_DiskDrive_Bottom.jpg
Image:Cumana_DiskDrive_Front.jpg
Image:Cumana_DiskDrive_Back.jpg
Image:Cumana_DiskDrive_Left.jpg
Image:Cumana_DiskDrive_Right.jpg
Image:Cumana_DiskDrive_Interior.jpg
</gallery>

[[Category:Hardware]]

User:Polluks

2021-10-11T12:38:39Z

Polluks:

https://sites.google.com/site/tandycocoloco/wordpak-rs
http://www.colorcomputerarchive.com/coco/Documents/Manuals/Hardware/Wordpak%20Users%20Manual%20(PBJ%20Inc).pdf

http://users.axess.com/twilight/sock/rs232.html
http://www.cocopedia.com/wiki/index.php/Deluxe_RS232_Pak

https://bitbucket.org/magli143/exomizer/wiki/Home

http://dragon32.info/info/romref.html [[CoCo ROM Equivalents]]

https://www.everygamegoing.com/litem/The-Hitchhikers-Guide-To-The-Galaxy/107786/ http://www.retrowiki.es/viewtopic.php?t=200033991

User:Polluks

2021-10-11T12:29:31Z

Polluks: Infocom

https://sites.google.com/site/tandycocoloco/wordpak-rs
http://www.colorcomputerarchive.com/coco/Documents/Manuals/Hardware/Wordpak%20Users%20Manual%20(PBJ%20Inc).pdf

http://users.axess.com/twilight/sock/rs232.html
http://www.cocopedia.com/wiki/index.php/Deluxe_RS232_Pak

https://bitbucket.org/magli143/exomizer/wiki/Home

http://dragon32.info/info/romref.html [[CoCo ROM Equivalents]]

https://www.everygamegoing.com/litem/The-Hitchhikers-Guide-To-The-Galaxy/107786/

User:Polluks

2021-10-11T12:21:58Z

Polluks: ROM

User:Polluks

2021-10-03T23:56:09Z

Polluks: Exomizer

User:Polluks

2021-10-03T21:42:03Z

Polluks: RS-232

User:Polluks

2021-10-03T21:39:49Z

Polluks: Wordpak

https://sites.google.com/site/tandycocoloco/wordpak-rs
http://www.colorcomputerarchive.com/coco/Documents/Manuals/Hardware/Wordpak%20Users%20Manual%20(PBJ%20Inc).pdf

Vbcc

2021-09-29T22:27:19Z

Polluks: Created page with "The '''vbcc''' cross compiler and its '''vlink''' linker support Dragon DOS. http://www.compilers.de/vbcc.html http://sun.hasenbraten.de/vlink/ Category:Software"

The '''vbcc''' cross compiler and its '''vlink''' linker support [[Dragon DOS]].

http://www.compilers.de/vbcc.html
http://sun.hasenbraten.de/vlink/

[[Category:Software]]

Dragon 32 - 64K Upgrade

2021-09-29T22:10:37Z

Polluks: /* Flex versus OS9. */

(Preliminary Version, 1st Revision - Sept. 1985)

'''Upgrading Dragon 32s to 64k of RAM'''

by R.W.Hall, National Dragon Users Group.

'''Disclaimer'''. Although every care has been taken in the preparation of these
notes, and the technical data have been checked, neither the author nor the User
Group accept any liability for inaccuracies or consequential loss or damage,
however caused.

== Introduction. ==

These notes are provided to help the adventurous upgrade their Dragon 32s
from 32k of random access memory (RAM) to 64k, and to give them a feel for
possible uses for the additional memory. The technical detail given is adequate
rather than exhaustive, and assumes that you have some competence at
electronics, and in the programming, an acquaintance with the hardware of the
machine, such as may be found` by reading say 'Inside the Dragon' (Smead &
Somerville, published by Addison—Wesley, 1983). The notes are based on articles
I wrote in Dragon Update, and the feedback that I received from other members of
the User Group.

== Is upgrading worthwhile?. ==

To answer this question let's compare the spec of the Dragon 64 with that of
a 32:-

The Dragon 64 currently retails for £195; it has twice as much RAM as the 32, an
RS232 interface, and two BASIC ROMs — the additional ROM is used when the 64 is
in '48k' mode. A Dragon 32 by contrast retails for £50 (if you can find one),
and secondhand fetches about £25—35. Changing the memory chips will cost you
well under £15 if you do it yourself (£40-60 if someone else does!), (and adding an RS232 interface - following the circuit in July 85 'Electronics & Computing' - would cost probably another £15). without the additional ROM however, the
additional RAM cannot easily be used by BASIC. So, if you don't have a disk
system, and always write in BASIC, upgrading to 64k is probably not going to be
useful to you - if however you know at least a smattering of machine-code or use
a language like FORTH, then even if you haven't got a disk yet, you'll probably
find the extra memory useful. If of course you have got a disk drive, you'll be
itching to make the mod.(?!).

== First Steps. ==

The circuit-boards in D32s come in half-a-dozen different varieties, but
there are two basic types - those having 8 32k (by 1bit) RAM chips, and those
having 16 l6k RAM chips. The former are rather easier to modify than the latter
(more common) types. To find out which sort you've got, type the following,
immediately after switching on:-

?PEEK(&HFF22) AND 4

If the answer is 0 then you've got an 8 by 32k system, if its 4 then your memory
is 16 times 16k chips - if you get any other answer, steady your trembling
fingers and try again!.

(The significance of this test bears explaining:-
when the Dragon is switched on, or when reset is pressed, a routine in ROM at
(hex) B3B4 is entered, which sets up the default settings of the two Peripheral
Interface Adapters (PIAs), the Video Display Generator (VDG) and the Synchronous Address Multiplexor (SAM); until the SAM has been set up correctly, the RAM
cannot be used. To set up the SAM however, the ROM routine on a D32 must know
the memory type, and the 2nd bit at FF22 is programmed as input and used for
this purpose. The D64 reset routine does not need to know the memory type, and the bit is instead used as an output signal to switch between the two BASIC
ROMs).

If you find that you have (8 times 32k) memory it is very likely that the
chips are in fact 'half—good' 64k units (they are often marked as OKI 3732s).

It‘s fairly straightforward to check if you do have these sorts of chips, by trying to write infomation to the uppermost 16K of the 64Kg (ie C000-FEFF, when there is nothing plugged in the cartridge port, (and then trying to recover
it), using the routine given in Appendix B. However, you won‘t be able to test
ALL of the upper 32k (if it exists) until you've made the mod. to the decoder
circuitry. This is, I suggest, the next step to make, in ALL cases.

== Modifying the Decoder Circuitry. ==

The modification to the decoder circuit is straightforward, and can be
added either externally or internally - however, it is only worth making the mod
externally (via a board in the expansion port) if you find you have 'half-good'
64k RAMs aboard, you have no diskdrive or intention to get one, and are happy to
discover and work with the imperfections in the memory. The internal mod uses a
spare gate on one of the 74LS02s - this is the same gate as some people have
used to add a 'reverse-video' (green-on-black instead of black—on-green) capability (see Update No. 5) — if you've added this you‘ll have to first remove
it and move it to another spare gate, wired as an inverter.

The details of both the internal & external mods are given in Figs 1 & 2.
Both perform a similar function — they stop the 74LSl38 (a '3-to-8 decoder')
from being activated when write-to-Memory is true. and thus prevent the BASIC &
cartridge ROMs being spuriously activated when writing to RAM in the memory map
above 32k. This circuit is functionally equivalent to that used by the D64 and
has the same side-effect, namely:-

If you have any device in the cartridge port between 8000 and FEFF which is
activated by the 'CART SEL" signal (pin 32), it will not be possible to WRITE
to this device: this is because 'CART SEL' is derived from the LS138 decoder. lf
the device is an I/0 device, then the correct solution is to move its address to
FF00 or above using P2 (pin 36) and address lines as the select device signals.
(If it's static RAM, you could separately decode the upper address lines, but do
you need it now anyway?; if so, see Appendix D for a possible fix).

The external mod could be built up on any of the prototyping boards which
are available from Tandy, Compusense or Windrush. However, these are fairly
expensive, certainly compared with the two logic gates which make up the
circuit; a cheaper option may be to use a 44 way plug and extender board for the
spectrum expansion port, and cut it down to 40 ways to fit the Dragon port.

It is possible to make the internal mod without removing the SAM and CPU,
provided you take the usual precautions against high voltages & static (earth
the iron, the board and you, and wear no nylon clothes). In detail the mod is as
follows:-

i) Check that IC26 is a 6821 (PIA), IC33 is a 74LS138, and IC3l a 74LS02 with
the gate on pins 1,2 & 3 unused.

ii) Now join pin 12 of IC31 to pin 3 of IC3l, and pin 2 of IC3l to pin 21 of
IC26 (this is just a convenient R/W line); (IC35, also a 682l PIA, may be more
convenient than lC26 on some boards). Reassemble, and check all still works.

iii) Then join pin l of IC31 to pin 5 of IC33; and finally, cut the connection
between pin 5 of IC33 and pin 8 of IC33 (this is easier than it sounds - however
the hardened steel tips of a good pair of miniature side cutters will do the
trick).

iv) Test out the circuitry -the effect on normal operation should be nil. If you have 'half-good' 64k RAMs aboard, you can now begin exploring their potential.

== Changing the RAM chips. ==

'''a) Preliminaries.'''

The first problem is to get hold of 8 64k RAM chips at a reasonable price.
Chips with an access time faster than 300ns will probably be good enough, and
the only real subtlety is to get hold of l28·-cycle refresh chips, not 256—cycle
refresh chips — this excludes in particular the Texas 4164 (but not the Toshiba
or HEC or Motorola 4l64s!). (The 6883 cannot properly refresh 256·cycle chips -
although these may be adequately refreshed, miles out of spec., by the action of
the 'VDG taking information from them). I give a possible list of suitable chips
and their suppliers in Appendix C - at the time of writing it should be possible
to purchase suitable chips at well below 21-50 each. Even at their present low
prices however, I suggest you socket the chips, since this makes fault tracing
much easier — suitable low-profile 16-pin DIL sockets cost about l2p each.

Before beginning the removal and replacement of the RAM chips I would suggest you remove the SAM and CPU (which are socketed) - removal should be
effected gently, using eg a thin-bladed knife to lever up the chip with as well
distributed a force as possible (again, with everything earthed!). wrap these
safely away (in tinfoil or on a conducting mat for maximum safety), before
turning attention to the main circuit board (- make the decoder mod. now, if you
have not already done so).

There are two common designs of mainboard in D32s - these are:-

1) the 'Issue 2' board, which comes in both (8 x 32k) and (16 x 16k) versions,
but with only 8 chips directly on the mainboard.

ii) the ‘Mark II' board which has room for all 16 (16k) RAM chips on the
mainboard.

You may well come across others, but the notes which follow should help you
through these too.

'''b)(8 x 32k) Machines.'''
Machines with (8 x 32k) memory chips are usually built on 'Issue 2'
mainboards, and the procedure for modifying them is straightforward - you must
remove the 8 old memory chips (usually numbered IC1-8), and replace them by
sockets, check out all lines and voltages, and install the new RAM chips. The
way you do the removing is largely dependant on personal skill and tools
available. I have used a chip extractor together with an IC desoldering
attachment on a moderate-wattage iron - others swear by desoldering braid, or a
solder extractor, whilst still others cut their losses and snip out the chips.

In all cases take care not to use excessive force, because the lines are plated through, and breaking the plating is a sure cause of later malfunction. Also be
warned that it is very easy to bridge lines with solder splashes, especially
just under the ICs, where the lines are not lacquered over and are very close
together. It is for this reason that I would embark on a systematic check that
all 8 address lines (Z0-7) and control lines CAS, RAS and WE between SAM and RAM
are independent, and that the 8·data lines in and out on each chip are also OK
(see Appendix A, & Figs). I think this test is most safely made with volts on
the board, using a low-voltage high-impedance ohms range on a multimeter (NB -
on some meters the highest impedance ranges use dangerously large battery
voltages). (It is wise to preceed this resistance check with a voltage check,
but note that lines with logic connected to them (Din, Dout, RAS and usually Z7)
give non-zero voltages). If bridges are found, it is often possible to clear
them, if you've··bought the right design of socket(!), by prising the plastic
surround away from the soldered in pins, to inspect the state of the lines
beneath.

'''c) (16 x 16k) Machines.'''

On these machines the l6 RAM chips are arranged electrically in two banks
of 8, which are activated by different 'Row Address Strobe' signals, RASO & RASI; the chips are usually MK4116s, ( or equivalents, eg MM5290s), and instead of having a single 5V supply (on pin 8), have -5v on pin 1, 5v on pin 9 and l2v
on pin 8 (-check these). These voltages (especially the l2v!) now need to be
rearranged (see the pinouts in Appendix C) for the 64k chips, which go in bank 0 (IC1-8) only. In addition the RASl signal needs bringing over from bank 1 (pins 4) to become the 8th address line (A7) on bank 0 (pins 9), and the SAM
initialisation routine needs informing of this change of duty by a change of the
signal on pin 12 of the PIA IC35 from high to low.

Owners or 'Issue 2' boards will find they can effect most of this by just
changing over jumpers - for owners of 'Mark II' machines the path is slightly
more thorny, but not as difficult as at first appears.

'''i) 'Issue 2' boards.'''

A lot of D32s of 82-83 vintage were built on 'Issue 2' mainboards. These had
room for only 8 chips on the mainboard, and often 8 OKI 3732s were fitted (see
above). However, they are even more common in their (16 x l6k) versions, when
the 8 extra memory chips were added in sockets above the others; or else a small
subsidiary ’patch' board was added, containing l0 RAM chips end the 74LS244 memory buffer - 6 RAM chips remained on the mainboard, with connections to the
patchboard taking up the space normally occupied by IC1, IC8 (RAMs) and ICl6
(74LS244).

To facilitate their use as either (8 x 32k) or (16 x 16k) boards, 5 jumpers
were fitted, just in front and to the right of the power supply connector
(looking from keyboard!). The positions of these jumpers are numbered on the
board from 1 to 10 (odd positions are at back), and they perform the following
functions (which, if you are in any doubt, you should verify!):-

a) The first (leftmost) jumper 'controls the inclusion, or not, of an inverter in the RASl/Z7 signal line. In position 1 there is no inverter, in position 2 there is.

b) The second jumper controls the voltage on pins l of the RAMs. In position 3
it is -5v, in position 4 it is +5v.

c) The third controls the voltage on RAM pins 8. In position 5 it is 12v, in
position 6 it is 5v.

d) The fourth controls the use of RAM pins 9. In position 7 there is +5v on the
pins, in position B it is RASl/Z7.

e) The fifth (rightmost) jumper controls the voltage on pin 12 of IC35. In
position 9 this is 5v, and in position 10 0v.

In (16 x 16k) mode the jumpers will be set to positions 1,3,5,7,9, and there `
will be a flying lead from position 8 taking the RASl signal to the patch-board.

The straightforward way to modify these boards is as follows:-

a) Remove the patch board and its connecting lines, saving the 74LS244;

b) Remove IC2-7, C12, C58 and any other capacitors on the line connecting pins 9
of IC1-8; remove also C59 and R66 on the RASO line.

c) Clean up the board, and fit 16 pin sockets in positions IC1-8, and a 20-pin
socket in ICl6.

d) Set the jumpers to l,4,6,8,l0

e) After checking all voltages and lines, install the 8 new memory chips in IC1-
8 and the 74LS244 in ICl6, ... and step back.

This method of modification produces a nice clean job, with everything easily
accessible in case of trouble. However the patchboard may well have its chips
installed in sockets, and it is then tempting to try installing the new memory
chips on this patch board. I suggest the following route, which is for an issue
1 patchboard, with the proviso that I gave up on it!

a) Remove IC2—7 etc from mainboard as described in b) above.

b) Remove IC1—l0, R1 & C23 from patchboard.

c) Take the flying lead, labelled ‘RAS1', from jumper position 8 and connect it
to the wire going to pin 4 of IC1 on the patchboard (ie to pick up RASO) it's
probably also worth linking the junction of R1 & C23 on the patchboard to the
junction of C59 & R66 on the mainboard, to produce the same effect.

d) Now for the catch - unfortunately, on the issue 1 patchboard, the 5v supply
to pin 20 of IC11 (the M74LS244) is chained in with the lines connecting pins 9
on IC1-10. This chain must be broken, and IC9 & 10 relinked to IC1-8. I suggest breaking the line, which runs underneath the board, under IC5 (at back edge of
board, near centre); and at the front righthand edge by ICl0. After reinstating
a connection between pin 9 of IC10 (by deft unseeable soldering!) and the wire
to pin 9 of IC1, the difficulties are (I think) over.

e) Set jumpers to 1,4,6,8,l0; check out

f) Put new memory chips in patchboard sockets IC2-7, IC9 & 10, and return
74LS244 to IC11 if you removed it .... now turn on, and the best of luck.

'''ii) 'Mark II' boards.'''

The sixteen memory chips are all installed on the mainboard and the two
banks are usually numbered IC1-8 (bank 0) and IC36-43 (bank l). Both sets of
chips are to be removed, but only ICl-8 are replaced with sockets. (NB
physically, the chips are arranged as a group of 9 and a group of 7 - IC43 is
next to IC8). Because there are no jumpers to help you on these boards all the
changes must be made by cutting/rerouting lines. These wiring changes are as
follows:~

i) the -5v line on pins l should be chopped (if necessary at both ends of the
bank) and left to float; I did this modification on my board, a Mark II, Issue
6, by cutting through the line on the underside of the board, near the PSU
socket, but just after the connection to TR4 and R69. On most boards the -5v
line is not a through-line, but in cases where it is the connection between the
two ends of the chain must be reinstated with a patch wire. (Note. The pins l
are not connected internally on most 64k RAMS - it is not nice to leave the -5v
line connected however, since on some chips'(eg Motorola 6665) this pin is
pulled up internally to +5v!; moreover if -5v is accidentally cross—connected to
any of the RAM, SAM or CPU chips it will blow them!).

ii) the +l2v line (on pins 8) must be similarly chopped - it in general is a
through-line (en route to the cartridge port) and so the through-circuit must be
completed by a tidy patch-wire.

iii) the +5v line (pins 9) is then chopped at both ends of the bank, and the
voltage diverted via the old 12v line connecting pins 8. I suggest you sever the
line between C12 & IC1, and again between ICs 8 & 43/C50.

iv) the old 5v line connecting pins 9 now becomes the eighth address line.
Remove any bypass capacitors on the line, then take a patch—wire from the line
to that connecting pins 4 of bank l. Using the old 5v line in this way as a `
signal line probably loads up the signal with rather more capacitance (80pf?)
than is present on the other address lines (because the land is quite wide) but
this does not seem to have any adverse affect on the circuitry — note that
connecting the signal across in the way suggested ensures the inclusion of the
22 ohm damping resistor (R12) between SAM and RAM;

v)when all this is done, it remains to change the signal on bit 2 of FF22.
This is done by disconnecting pin l2 of IC35 (682l, PIA) from R73 (a 'pull-up'
resistor connected to 5v), and wiring it to ground.

This ends the mods - a subsequent careful test of all voltages on the RAM,
SAM & CPU sockets, followed by a systematic test for bridges or other errors,
prior to replacing the chips, is particularly recommended (-see remarks in 5b).

Testing out by software in the event of malfunction is largely fruitless,
because most faults lead to totally dumb systems - however, provided you have
checked that the voltage rails are correct (and in particular that the -5v and
l2v lines have been routed away from the RAM), all changes should be reversible.
(Note that failing to perform step v) (or equivalently on an Issue 2 board,
failing to change jumper 5 from posn 9 to posn 10 ) will produce a running
system but with only l6k of memory visible to BASIC.

'''d) Jokers in the Pack!.'''

In the cut—throat world of micro-manufacturing, Dragon Data seemed to have
shown commendable ingenuity to use what components they could get hold of, especially RAM chips. The result is that although the three boards described
above are the most common, there exist a number of less common varieties, of
which I don't have 'hands-on' experience. One of these is the so—called 'Siemens' board, built using 8 Siemens HYB-4232s. Though numbered as if 32k
chips, these were in fact double l6k units. They were 18-pin chips but were
installed on issue 2 boards, and the instructions given above should suffice to
see you through.

Secondly, there are later versions of the ‘patchboard', I believe, and on
some of these DD actually installed 32k chips! A careful inspection of your
board. (if it's not an Issue 1, dealt with above, and if it doesn't already
contain only 8 x 32k chips, when the answer is clear!), should tell you if its worth keeping in place or not.

In all cases of doubt, make sure you arrive at the connections between the
principle components outlined in Appendix A.

== What can be done with it all. ==

Lets now turn to ways of using the new memory which do not require a disk-
drive.

When the Dragon is first switched on, it is in Memory-Map Mode 0, and the
new 32k of RAM is tucked away out of sight. To access the new memory we must
either switch to Map Mode l, or switch from Page 0 to Page 1 in Map Mode 0. In
Map Mode 1 the new memory occupies 8000 to FEFF and we have no access to the
BASIC & cartridge ROMs; neither can we access the last 256 bytes of RAM (FF00-
FEFF) which are reserved for I/O. In Map Mode 0, Page 1, the SAM automatically
adds 32k to the cpu (but not VDG) addresses before sending them to RAM so that
the new memory appears to lie at 0-7FFF (in place of the true lower memory,
which is now inaccessible). in all three modes however (Map Mode 0, Page 0; Map
Mode 0, Page 1; Map Mode 1), the VDG has access to all 64k of RAM (and never to
the ROM), which it sees in the 'correct' order.

It's fairly straightforward to get from Map Mode 0 to Map Mode 1, and vice
versa, in machine code or FORTH (in fact any language which doesn't need the ROM
routines for a bit). by toggling the addresses FFDF & FFDE (see Appendix A) -
but you must turn the interrupts off first. An example of this is given in
Appendix B, program 1, which is a routine to copy blocks of data between low &
high RAM. or between ROM and high RAM. It may be used to copy the BASIC &
Cartridge ROMs into high RAM, and then run them — it is then possible to
customise the BASIC/DOS and also have easy access to the memory from E000 to
FEFF.

Program 2 uses a high-res text generator (NOT provided!) resident in high- `
memory to write text from BASIC on to a high-res screen, also in high memory.
(This routine thus effectively gives BASIC routines use of 8k of graphics RAM
for nothing - note that it makes use of the fact that the VDG will continue to
display from high memory, whilst the processor is in Map Node 0.,)

Access to and from Map Mode 0, Page 1, requires care, because the system
stack has to be reset each time; page-switching is achieved by toggling addresses FFD4 or FFD5, again with the interrupts disabled. In program 3 the two
pages are used to give two wholly independent areas for BASIC, so that two
independent 32k programs can be run. There is no reason why the two programs
need be wholly independent however, once the essential features of the
changeover are understood.

In all these investigations of the Dragon's Memory Modes, the Motorola data
sheet for the MC6883 (reproduced in 'Inside the Dragon') makes an invaluable, if
concise, reference.

== Flex versus OS9. ==

Many people contemplating upgrading to 64k have an eye to running either OS9
or Flex; (NB OS9 is not available for Premier 'De1ta' disk systems).

Both Compusense Flex and Dragon Data OS9 operating systems will work with an
upgraded machine (provided you've done the decoder mod.!) - however, whilst Flex
will boot up straightaway, a slightly more roundabout method is needed for OS9,
because the absence of an RS232 port at FFO4-8 causes the bootstrap routine to
hang up. To get round this, proceed as follows:-

i)type 'BOOT" - the words 'OS9 B00T' should appear on the screen; and a few
seconds later all disc activity ceases, but with the disk still selected and turning.

ii)press reset.

iii)type 'POKE &HFF03,&H34: EXEC9736'.

Success should then be yours.

A brief comparison of the advantages of the two systems may be useful.:-

Flex is structurally simpler than OS9, being essentially a single-user, single
task operating system of mid 70's vintage; it has been described by Mike James
(in ‘The 6809 Companion*) as 'almost without argument the standard operating system for the 6800 and certainly the best single-user operating system for the
6809'. By contrast, OS9 is rather complex, being multi—user and multitasking;
the multi-user facility is largely academic for Dragon users, and the main use
of multi-tasking is to run a 'background job' to the printer whilst proceeding
with something else on the screen - there just isn't enough memory to do much
else anyway. ('Printer—spooling’ is a feature of some implementations of Flex,
but Compusense decided not to implement it on the Dragon for rather purist
reasons). The Flex system comes with a 5l oy 24 character set, with a facility
for windows; the 5l by 24. character—set is optional in OS9 (type 'G05l' to get
it) but when it is installed, there is only about 40k of userspace free, as
against 48k for Flex. where OS9 scores is on the availability of cheap(ish)
software - even before the recent price cuts by Touchmaster and Cotswold
Computers the OS9 packages were more attractively priced that their Flex
counterparts, and with the recent dramatic price reductions this is now even
more true. (This is rather paradoxical, since one of the claimed advantages for
Flex is the wealth of software available for it - there is, from specialist
firms like Windrush, it you'll pay £300 a time!). The only readily available
software for Flex is the editor/assembler, DBASIC, RMS (also available under
OS9), and a wordprocessor. The assembler is quite nice (it allows 'macro's'),
but not perfect (eg. it doesn't optimise the code for PC-relative forward
references ); the editor is an oldfashioned line—editor, as is the the OS9 one;
DBASIC is essentially a copying-over of the Microsoft ROM into RAM it has its
uses but has none of the speed or aids to structured—programming of OS9's
BASICO9. (And I haven't tried the Flex word-processor, but this is written using
OS9 Stylograph). Overall, I feel that the Flex Editor/Assembler is a very powerful package for developing machine—code programs, but OS9 has more to offer
in other lines (eg C & Pascal), if you can live with its memory limitations. At
the end of the day it's the old tale of horses for courses - why not play safe
and buy both??!!!

== The Future - 256k? ==

256k RAM chips are now the same price 64k chips were 18 months ago (13-50 or
so). These chips have the same pinout as the 64k ones, except that pin l is now
used for a 9th multiplexed address line. A recent article ln BYTE (September 85,
pages 247 to 254) showed how such chips could be incorporated on the Atari
80OXL, and how the refresh problem (all 256k chips are 256-cycle refresh) could
be overcome; it is likely that a similar method could be applied to the Dragon
(or 'CAS before RAS' refresh could be implemented). The outstanding problem is
how to manage the memory map (the Atari already has a dedicated register for
this), and who will produce software to run on a 256k machine. A suitable
'Rolls-Royce' quality memory management unit for the 6809 does already exist ··
it's called the Motorola 6829 and costs about £25. If you're prepared to install
one (NOT trivial!) you could in principle have a machine capable of running OS9
Level Two (if you can persuade someone to sell this you). Ordinary mortals
however, would be advised to wait awhile, until Messrs Compusense & Eurohard
sort out their own upgrade path. If you socketed your chips, you can wait safe
in the knowledge of being prepared for the next leap forward.

== And Finally... ==

I'd like to acknowledge helpful feedback from Paul Grade, John Bussell, Alan
Butler, Arne Eriksonn, and John Payne. I hope that you find these notes useful.

== APPENDICES. ==

'''Appendix A. Memory Control on The Dragon.'''
The MC6883/74LS783 Synchronous Address Multiplexor or SAM plays the central
role in the architecture of the Dragon, interfacing the control of the RAM,
ROMs, 6809E cpu, and VDG, and providing the E and Q clocksignals. All this is
accomplished in a standard IC package of only 40 pins, and the penalty for this
is that, having no connection to the cpu data bus, the SAM must receive its
orders from the cpu on the address bus. 32 addresses, from FFC0 to FFDF, are
used for this purpose, and control l6 bits of information; writing (anything!)
to the odd addresses sets a bit, whilst writing to the even addresses clears it.

Most well—known of these operations is the so-called 'speed-up poke' (POKE&HFFD7,0 and its reverse, POKE&HFFD6,0); however, of more concern to us
here is the Map Type Bit (TY), set by FFDF, cleared by FFDE; the Page Bit (Pl),
set by FFD5, cleared by FFD4; and the Memory Size Bits (M0 A Ml) set/cleared by
FFDB/FFDA & FFDD/FFDC respectively. Of the remaining addresses, FFD6 to FFD9
control the 2 clockrate bits (R0 & R1); FFC6 to FFD3 control 7 bits (F0 to F6)
giving the base address of the current Video-RAM (in units of 512 bytes); and
FFC0 to FFC5 control 3 VDG Mode bits (V0 to V2).

The SAM interleaves requests from the cpu for data, with providing data. for the VDG. Depending on the map mode and the memory address sent out by the cpu,
the SAM will either pass on the address required to RAM, or will activate a ROM
or output device, (via signals sent to the LSl38 decoder); meanwhile, the
address of the next byte in video-RAM for output to the VDG is generated in the
SAM itself.

There is more in passing an address to RAM than meets the eye, because to
reduce the size and complexity cf the RAM chips, the address is presented in `
two parts, called the row address and column address; this is the 'address
multiplexing' process for which the SAM gets its name. when 32k or 64k chips are
in use, the SAM first presents the lowest 8 bits of the address to the RAM chips
on its output lines Z0 to Z7, and asserts the Row Address Strobe (RAS); about
0.1 microseconds later (!) it presents the upper half of the address on the same
lines, and asserts the Column Address Strobe (CAS) - about 0.1 to 0.2
microseconds later again, the data output from the RAM chip has stabilised, and
is read on the data bus (-or, if write-enable (WE) is activated, data is read
from the bus into memory). Now when l6k RAM chips are used, only 7 lines (Z0 to
Z6) are needed for addressing; Z7 is now programmed (via Ml) to act as a second
Row Address Strobe (RASl), thus allowing the use of two banks of 16k chips.

Finally, thc SAM controls the 'refreshing' of the RAM chips., Dynamic RAM
chips have a simple structure of one transistor and capacitor per bit (or cell),
and the charge leaks away from the capacitor over a few tens of milliseconds.
The RAMs are so constructed however that everytime a row address is presented to
them, all the cells with this row address have their information read out into buffers - later in the cycle this information (or new information if there is a write-to—memory) is read back into the capacitors, so that the whole row is refreshed at once. The SAM inserts a series of these 'RAS-only refresh cycles' from time-to-time to keep all the cells updated. As a final subtlety, not all
256 RAS combinations need to be addressed on most chips, only 128. However some
chips (notably the Texas 4161) do require 256 refresh addresses, and cannot be
refreshed by the 6883.

'''Layout of the Dragon.'''

Both Dragon & Tandy machines closely follow the recommended circuit given by
Motorola in the MC6883 data sheet. On all the boards the SAM output lines (Z0-
Z6, RAS0, RAS1/Z7, CAS & WE) are linked to the corresponding rails on the RAMs
(A0-A6, RAS or A7, CAS & WE) by low—value damping resistors; on the 'Issue 2'
boards however, there is optionally also an inverter between Z7 and A7,
presumably to allow the good upper half of 'half-good' 64k RAM: to be used where
appropriate; it can safely be left in circuit when upgrading. As for the data
lines on the chips, the inputs Din are connected directly to the data bus from the cpu, whilst the outputs Dout (marked as 'Q' on most RAM datasheets!) go via
a 74LS244 buffer on to the date bus, and via a 74LS273 latch to the VDG; data is
strobed into the latch under control of RAS0, whilst the 74LS244 memory buffer
is activated by a signal from the 74LSl38 decoder (which in turn decodes signals
50,51,52 from the SAM -· see block diagram, Fig 4). Note that, on MkII & Issue 2
mainboards, IC1 is connected to data line D7, and so on in reverse order til
IC8, which is connected to D0.

'''Appendix B. Some programming examples'''.

The three programs given in listings L1 to L3 have already been briefly introduced in the main text. At the heart of each are a series of short machine-
code routines; these are coded in hexadecimal and placed in BASIC DATA
statements, (one instruction per statement). The surrounding BASIC program loads
the the machine code, by default into the cassette buffer at (hex) 2OO, and then
where necessary modifies it, or installs jumps in the appropriate BASIC
input/output hooks. As a rule these m/c routines perform their manipulations
with the interrupts turned off -· this is because in normal operation the
interrupts are vectored, by jump instructions in locations (hex) 100 to ll2,
into routines in ROM; unless both the vectors and service-routines are copied
over to RAM the system will crash when an interrupt occurs. The most frequent
interrupt comes from the 50Hz clock, which can be turned off separately, in
BASIC, by executing 'POKE&HFF03,&H34'.

Program l: Here the machinecode begins by saving all registers and turning
interrupts off : it then executes a simple loop in which data is picked up from
an address pointed to by X, in one map mode, and deposited in the address given
in the Y register, in another map mode. The map mode for picking up the data,
for depositing it, and the final map made to return to, are all set up by BASIC,
as are the start & finish addresses in the first field, and the start address in
the second. By copying from 8000 to E000 (if you have a disk, BFFF if not) in
mapmode 0, to 8000 on in mapmode 1, and returning to mapmode 1, you will
smoothly transition from running BASIC in ROM to running it in RAM, giving space
for machinecode etc from E000 (C000) to FEFF.

Program 2: This uses the Compusense Flex High—Res text—generator resident in
RAM above 32k to write text from BASIC to a high-res graphics screen at E6OO in
RAM. The text has true lower—case, and a 51 by 24 format. (A similar arrangement
could probably be made with other similar text-generators.)

T0 use the program first boot Flex (not provided!) and turn off any options
set for the terminal (eg unset 'pause at end of page' by typing 'TTYSET, DP=0'),
then type 'MON' to return to normal BASIC. Finally load and run the program -
the BASIC may be deleted after it has run, leaving the m/c routines.

The program works by intercepting the BASIC 'output a character' hook; if
the output is heading, for the disk, cassette or printer (9D nonzero) then it is
sent on its way — (the version shown assumes you have DragonDos, so amend line
A0 to 39,12,12 if not). If the output is heading for the screen, then the map
mode is changed to 1 and the Flex 'output a character' routine or the 'output a
crlf' routine entered; (the addresses of these and other useful Flex routines
nrc to be found `in the Flex 'Advanced Programmers Guide'). Finally, it is
necessary to keep the VDG looking at the right graphics screen, since there 5is a BASIC routine called everytime a character is input which resets it to look at
the normal text screen at (hex) 400. A simple modification is hacked into the
input ram hook no achieve this.

Program 3: This program uses pageswitching, to run two independent BASIC or
machinecode programs in the two 32K pages of memory. The program is configured
to run with DragonDos, and to remove this feature change line 140 (JMP $D917) to
'14O DATA 39,l2,l2'.

The code comprises 3 sections: SWOPIT, which dumps the stack pointer in
"HOLE", switches pages, and reloads the SP from the corresponding location in
the other page; VDC, which keeps the Video Display looking at the right text-
screen (400 in page 0, 8400 in page 1); and finally MOVIT, (a derivative of program l), which sets up Page 1 initially, by copying page 0 into it and then
modifying some locations.

After running the BASlC, type MON to remove the redundant code, but leave
the machinecode. Typing or executing 'EXEC' will enter SWOPIT, and send you to
the other page. SWOPIT could also be linked into the 'End—of-BASIC-line' hook at
l9A—l9C, or at a pinch into the 50Hz interrupt routine. The routine will work
correctly (?!) for all BASIC programs which use text only, and m/c routines
which use the BASIC I/O. It will also generate graphics correctly, but in Page 1
will not display them unless the BASIC statement 'SCREEN a,b‘ is expanded to
‘SCREEN a,b: POKE &HFFD3,0' (and equivalently for m/c programs).

'''Use of FORTH.''' Those wishing to use FORTH will find it easy to change
map/page modes by defining words such as C64, thus:-

HEX : C64 0 FFDF C! ;

However; you will need to turn interrupts on and off — the following FORTH
word, CLOCKOFF, would usually be sufficient,

HEX : CLOCKOFF 34 FF03 C! ;

but a more satisfactory solution is to define e words IOF and ION in machinecode
as follows:-

HEX CREATE IOF
1A50 , AEAl , 6E94 , SMUDGE
CREATE ION
1CAF , AEAl , 6E94 , SMUDGE
DECIMAL ;S

(This screen should work with Oasis/Dragon Data & Tele-Forths. The m/c AEA1,
6E94 translates as LDX ,Y++ :JMP (,X) and is the 'in-line ' code for the FORTH
terminating-word 'NEXT').

'''Appendix C'''

Some suitable 64k RAM chips and their suppliers.

{|{{PrettyTable|width: 700px; font-size: 2em;}}
|''Manufacturer''||''Number''||''Possible Stockist**''||''Telephone''
|-
|Oki ||M3764 ||Manhattan Skyline ||0628-75851
|-
|Hitachi ||HM4864 ||Farnell ||0532—636311
|-
|Motorola ||MCM6665 ||STC ||0279-26777
|-
|Mostek ||MK4564 ||Celdis ||0734-586191
|-
||NEC ||PD4l64 ||Farnell ||0532—636311
|-
|Toshiba ||TMM4l64 ||Verospeed ||0703-644555
|-
|}

All of these have the same pinout (see fig C2), with pin 1 being marked as N/C,
except tor the MCM6665, for which the pin is connected internally to 5V; also
given in the figure (Cl) is the pinout of a typical 16k memory chip (MK4ll6),
usually fitted to the Dragon 32.

All the 64k chips above are 128-cycle refresh types (in contrast to the Texas 4l64 which is a 256—cycle chip and is not suitable).

**Finally, the stockists listed above are (apart from Manhattan Skyline)
often not the best sources for small quantities . The following four firms,

Technomatic (O1-208—1177)
Midwich Computer Co. (0379-898751)
Watford Electronics (0923-37774)
Happy Memories (054-422-618)

have recently been offering suitable chips at very competitive prices (eg less
than £l a chip for HM4864s at Happy Memories). Check the latest position in
T 'Wireless World' & ‘Electronics & Computing'.

'''Appendix D''' An alternative decoder mod., allowing use of static RAM in the
cartridge port.

The decoder modification suggested in the main text is the logical one to
use following the Motorola data sheets, and is essentially the same as that
employed on the Dragon 64. However, it does have the disadvantage of not easily
allowing static RAM in the cartridge port, because the cartridge-select line is disabled during all write operations. It appears that the following alteration to the internal mod. would overcome this:- instead of gating the decoder logic (IC33,74LS138 & IC31,74LS02),with R/W (the read/write line from the processor), the signal WE (write-enable) is used. To do this, connect pin 2 of IC31 to the land joining pins 3 of the RAM chips (rather than to pin 21 of IC 26); the other connections, between LS02 and LS138, remain the same.

It must be emphasised that this is a rather speculative mod., using an undocumented property of the WE signal - namely, that WE does not go low when memory above 7FFF is addressed in Map Mode 0 - this has been determined by experiment only!

For this reason, I do not recommend this mod. Having said this, it would be a great convenience to have static RAM available in this way when using the page—switch facility, since the system stack and a data interchange area could be maintained in it ( contrast Program 3 of Appendix B).

'''PROGRAM 1.'''
{|{{PrettyTable|width: 700px; font-size: 2em;}}
|''BASIC''||''ASSEMBLER''||''Comment''
|-
|10 ‘MOVIT 23-JAN—84
|-
|20 DATA 34,7F ||PSHS X,Y,A,B,DP,CC,U ||Dump the lot
|-
|30 DATA 1A,50 ||ORCC #$50 ||Interrupts off
|-
|40 DATA 8E,00,00 ||LDX #0000 ||Nasty impure instruction
|-
|50 DATA 10,8E,00,00 ||LDY #0000 ||And this
|-
|60 DATA B7,FF,00 ||STA $FF00 ||Will be FFDF or FFDE
|-
|70 DATA A6,80 ||LDA ,X+ ||Pick up Data
|-
|80 DATA B7,FF,00 ||STA $FF00 ||Will be FFDE or FFDF
|-
|90 DATA A7, A0 ||STA ,Y+ ||Dump Data
|-
|100 DATA 8C,00,00 ||CMPX #$0000 ||Another modified address
|-
|110 DATA 2F,F1 ||BLE L ||if less go round loop
|-
|120 DATA B7,FF,00 ||STA $FF00 ||Final map mode here
|-
|130 DATA 35,FF ||PULS X,Y,A,B,DP,CC,U,PC ||All done.
|-
|140 '
|-
|150 PRINT"movit here":PRINT"GIVE ME`A HOLE TO LIVE IN",: INPUT BA
|-
|160 IF BA>30O GOTO 170 ELSE BA=512
|-
|170 FOR I=BA TO BA+30
|-
|180 READ V$:V=VAL("&H"+V$)
|-
|190 POKE I,V
|-
|200 NEXT I
|-
|210 PRINT"TAKE`DATA FROM";:INPUT ST,FI
|-
|220 PRINT"IN MAP MODE 0(32K) OR 1(64K)";: INPUT MI
|-
|230 PRINT"AND PUT IT AT";; INPUT NA
|-
|240 PRINT"IN MAP MODE"; INPUT MO
|-
|250 PRINT"RETURN TO 32K(0) OR 64K(1) MODE"; INPUT MR
|-
|260 IF MR=0 THEN POKE BA+28,&HDE ELSE POKE BA+28,&HDF
|-
|270 IF MI=0 THEN POKE BA+13,&HDE ELSE POKE BA+13,&HDF
|-
|280 IF MO=0 THEN POKE BA+18,&HDE ELSE POKE BA+18,&HDF
|-
|290 X=INT(ST/256): Y=ST—256*X
|-
|300 POKE BA+5,X: POKE BA+6,Y
|-
|310 X=INT(FI/256); Y=FI-256*X
|-
|320 POKE BA+22,X: POKE BA+23,Y
|-
|330 X=INT(NA/256): Y=NA-256*X
|-
|340 POKE BA+9,X; POKE BA+10,Y
|-
|350 EXEC BA
|-
|}

'''PROGRAM 2.'''
{|{{PrettyTable|width: 700px; font-size: 2em;}}
|''BASIC''||''ASSEMBLER''||''Comment''
|-
|10 'FLEXIT 8-MAR-85
|-
|20 DATA 0D,6F ||Start TST $6F ||Cheek ouput device
|-
|30 DATA 27,03 ||BEQ SCRN ||If 0 ir's O/P to screen
|-
|40 DATA 7E,D9,17 ||JMP $D917 ||If anything else send to DOS hack
|-
|50 DATA 32,62 ||SCRN LEAS 2,S ||Drop return address off stack
|-
|60 DATA 34,7F ||PSHS X,Y,A,B,U,DP,CC
|-
|70 DATA 1A,50 ||ORCC #$50 ||IOF
|-
|80 DATA B7,FF,DF ||STA $FFDF ||Map mode 1
|-
|90 DATA 81,0D ||CMPA #$0D ||CRLF?
|-
|100 DATA 27,0A ||BEQ CRLF
|-
|110 DATA BD,CD,l2 ||JSR $CD12 ||Char O/P
|-
|120 DATA B7,FF,DE ||FINISH STA $FFDE ||Map mode 0
|-
|130 DATA 8D,07 ||BSR RESET
|-
|140 DATA 35,FF ||PULS X,Y,A,B,U,DP,CC,PC
|-
|150 DATA BD,CD,24 ||CRLF JSR $CD24
|-
|160 DATA 20,F4 ||BRA FINISH
|-
|170 'CHANGE VDG PAGE
|-
|180 DATA 34,02 ||RESET PSHS A
|-
|190 DATA 86,F0 ||LDA #$F0
|-
|200 DATA B7,FF,22 ||STA $FF22 ||Set VDG mode
|-
|210 DATA B7,FF,C5 ||STA $FFC5 ||Now set
|-
|220 DATA B7,FF,C3 ||STA $FFC3 ||VDG
|-
|230 DATA B7,FF,C0 ||STA SFFC0 ||Base page
|-
|240 DATA B7,FF,D3 ||STA $FFD3 ||to
|-
|250 DATA B7,FF,D1 ||STA $FFD1 ||$E600
|-
|260 DATA B7,FF,CF ||STA SFFCF ||which is where
|-
|270 DATA B7,FF,CC ||STA $FFCC ||the FLEX
|-
|280 DATA B7,FF,CA ||STA $FFCA ||HIRES
|-
|290 DATA B7,FF,C9 ||STA $FFC9 ||textscreen
|-
|300 DATA B7,FF,C7 ||STA $FFC7 ||lives
|-
|310 DATA 35,82 ||PULS A, PC ||All done
|-
|320 '
|-
|330 CLEAR 500
|-
|340 PRINT"flexit here":PRINT"GIVE ME A HOLE TO LIVE IN";; INPUT BA
|-
|350 IF BA>100 GOTO 360 ELSE BA=512
|-
|360 FOR I=BA TO BA+73
|-
|370 READ V$:V=VAL("&H"+V$)
|-
|380 POKE I,V
|-
|390 NEXT I
|-
|400 X=BA:Y=INT(X/256):Z=X-256*Y
|-
|410 POKE &H169,Z
|-
|420 POKE &H168,Y
|-
|430 POKE &H167,&H7E
|-
|440 X=BA+35:Y=INT(X/256);Z=X-256*Y
|-
|450 POKE &H16C,Z
|-
|460 POKE &H16B,Y
|-
|470 POKE &H16A,&H7E
|-
|}

'''PROGRAM 3.'''
{|{{PrettyTable|width: 700px; font-size: 2em;}}
|''BASIC''||''ASSEMBLER''||''Comment''
|-
|10 'HOLE STACK STORED HERE ||HOLE FDB 0 ||Stack stored here
|-
|20 DATA 0,0
|-
||30 ‘SWOPIT- SWITCHES PAGES ||SWOPIT PSHS A,B,X,Y,U,DF,CC
|-
|40 DATA 34,7F
|-
|50 DATA 1A,50 ||ORCC #$50 ||IOF
|-
|60 DATA 1O,EF,8C,F6 ||STS HOLE, PCR
|-
|70 DATA 32,8C,75 ||LEAS SWOPIT+$80, PCR ||In case of NMI?
|-
|80 DATA B7,FF,D4 ||LSI STA $FFD4 ||Flip page
|-
|90 DATA 10,EE,8C,EC ||LDS HOLE,PCR
|-
||100 DATA 35,FF ||PULS PC,A,B,X,Y,U,DP,CC
|-
||110 'VDG - CHANGE VDG PAGE
|-
|120 DATA 7D,00,6F ||VDG TST $6F ||Find if O/P to
|-
|130 DATA 27,03 ||BEQ LV2 ||screen
|-
|140 DATA 7E,D9,17 ||JMP $D917 ||DragonDos hook
|-
|150 DATA BD,80,0C ||LV2 JSR $80OC ||Put char on scree
|-
|160 DATA 32,62 ||LEAS 2,S ||Drop return address off
|-
|170 DATA 34,16 ||PSHS X,B,A ||stack
|-
|180 DATA 8E,FF,C8 ||LDX $FFC8 ||SAM VDG bits start
|-
|190 DATA A7,0A ||LVI STA $A,X
|-
|200 DATA 7E,A9,41 ||JMP $A94q ||Now rejoin ROM Reset
|-
| || ||routine
|-
|210 'MOVIT ~ SETUP INITIAL CONFIG
|-
|220 DATA 34,7F ||MOVIT PSHS A,B,X,Y,U,DP,CC
|-
|230 DATA 1A,50 ||ORCC #$50
|-
|240 DATA 85,00,00 ||LDX #$0000
|-
|250 DATA 10,8E,80,00 ||LDY #$8000
|-
|260 DATA B7, FF,DF ||STA $FFDF ||Mapmode 1
|-
|270 DATA A6,80 ||LM1 LDA ,X+
|-
|280 DATA A7,A0 ||STA ,Y+
|-
||290 DATA 8C,7E,FF ||CMPX #$7EFF
|-
|300 DATA 2F,F7 ||BLE LM1
|-
|310 DATA 86,D5 ||LDA #$D5
|-
|320 DATA A7,8C,C6 ||STA LSI+2, PCR
|-
|330 DATA 4A ||DECA
|-
|340 DATA A7,8D,7F,C1 ||STA LSI+$8002, PCR
|-
|350 DATA 86,0A ||LDA #$0A
|-
|360 DATA A7,8C,D6 ||STA LV1+1, PCR
|-
|370 DATA 4C ||INCA
|-
|380 DATA A7,8D,7F,D1 ||STA LV1+1$8001, PCR
|-
|390 DATA B7,FF,DE ||STA $FFDE ||Mapmode 0
|-
|400 DATA 35, FF ||PULS PC,X,Y,A,B,U,DP,CC
|-
|410 '
|-
|420 CLEAR 500
|-
|430 PRINT"swapit here":PRINT"GIVE ME A HOLE TO LIVE IN";:INPUT BA
|-
|440 IF BA>300 THEN BA=512
|-
|450 SWOPIT=BA+2;VDG=BA+22:MOVIT=BA+45
|-
|460 FOR I=BA TO BA+92
|-
|470 READ V$:V=VAL("&H"+V$)
|-
|480 POKE I,V
|-
|490 NEXT I
|-
|500 EXEC SWOPIT
|-
|510 X=VDG:Y=INT(X/256)=Z=X-256*Y
|-
|520 POKE &H169,Z
|-
|530 POKE &H168,Y
|-
|540 POKE &H167,&H7E
|-
|550 EXEC MOVIT
|-
|560 EXEC SWOPIT
|-
|570 EXEC SWOPIT
|-
|}

[[Category:Documentation]] [[Category:Hardware]]

DriveWire

2021-09-29T22:02:40Z

Polluks: Category

== Overview ==

DriveWire is a way to connect your Dragon to a PC. It allows you to transfer files from the PC to your Dragon, or to use the PC as a virtual disk for the Dragon. A server program runs on the PC and services requests from the Dragon. Instead of a PC, a stand-alone DriveWire server like the [[uDW SD-card DriveWire microserver|uDW]] can be used.

== DriveWire software ==

DriveWire on the Dragon uses the printer port. On the Dragon, software is needed that can "talk" to the DriveWire server through the printer port. Operating systems like HDB-DOS and [[NitrOS-9]] have support for DriveWire, and can use the DriveWire server as a full replacement for a normal floppy or hard disk drive. See [[Drivewire for dummies]] for how to use HDB-DOS and DriveWire.

For Dragon there is also [[DWLOAD]] - a small program that can be used to load programs from the DriveWire server without needing a disk operating system. DWLOAD can be embedded in a modified BASIC ROM, replacing the "DLOAD" command.

== DriveWire adapters ==

On the Dragon you will need an adapter to convert the printer port signals to a compatible serial port (or USB virtual serial port).

See [[Dragon_32/64_Drivewire_Adapter]].

== DriveWire server software ==

The Drivewire4 (DW4) server is a Java application and can be downloaded here: https://sites.google.com/site/drivewire4/download

A lightweight alternative is "DriveWire Lite": A reimplementation in C of the server side of the DriveWire 3 protocol: http://sourceforge.net/projects/dwlite/

There is also an open-source DriveWire server written in Python: https://github.com/6809/DwLoadServer

There is a Python based Drivewire 4 compatible server here: https://gitlab.com/sorchard001/dwlserve -
''"Minimal DriveWire server written in python, implementing a small subset of functions mainly to support Tormod Volden's dwload software for Dragon computers."''

== Drivewire4 (DW4) server usage ==

Just choose CoCo2 in the DriveWire4 server "Simple Config Wizard".
Keep all the default selections.

If you would like to use the server under Windows without installing the JRE, use this batch file for startup:
<pre>
SET JDK=%~dp0\jre
SET JAVA_EXE=%JDK%\bin\java.exe
"%JAVA_EXE%" -XX:+UseConcMarkSweepGC -jar DW4UI.jar --backup &
pause
</pre>
Download a JRE and put it into DriveWire directory together with this batch file.

== Links ==

* [https://sourceforge.net/p/drivewireserver/wiki/DriveWire_Specification/ DriveWire specification]

[[Category:Documentation]] [[Category:XRoar]] [[Category:Drivewire]]

Orchestra 90

2021-09-29T21:51:42Z

Polluks: Category

The Orchestra-90 CC was a Program Pak that plugged directly into the Color Computer.

[[Category:XRoar]] [[Category:Hardware]]

Orchestra 90

2021-09-29T21:49:55Z

Polluks: Created page with "The Orchestra-90 CC was a Program Pak that plugged directly into the Color Computer. Category:Hardware"

The Orchestra-90 CC was a Program Pak that plugged directly into the Color Computer.

[[Category:Hardware]]

Memory Map

2021-09-29T21:33:06Z

Polluks: /* INPUT/OUTPUT ADDRESSES */

== MEMORY MAP ==

DRAGON 32 and 64 in 32 mode

<pre> 0 - 1023 0000 - 03FF SYSTEM USE
1024 - 1535 0400 - 05FF TEXT SCREEN
1536 - 3071 0600 - 0BFF GRAPHICS: PAGE 1
3072 - 4607 0C00 - 11FF PAGE 2
4608 - 6143 1200 - 17FF PAGE 3
6144 - 7679 1800 - 1DFF PAGE 4
7680 - 9215 1E00 - 23FF PAGE 5
9216 - 10751 2400 - 29FF PAGE 6
10752 - 12287 2A00 - 2FFF PAGE 7
12288 - 13823 3000 - 35FF PAGE 8
13824 - 32767 3600 - 7FFF PROGRAM USE
32768 - 49151 8000 - BFFF BASIC ROM
49152 - 65279 C000 - FEFF CARTRIDGE USE
65280 - 65535 FF00 - FFFF INPUT/OUTPUT
</pre>

PLEASE NOTE:
With disks in use, the Disk work space occupies the first
page of graphics (1536 to 3071) and in consequence Graphics
screens are moved up one page, starting at 3072 (&H0C00) and
ending at 15359 (&H3BFF).
On start up the Dragon does a PCLEAR4 and in consequence the
memory available for program use starts at 7680, or 9216
with the DOS Controller in place.

DRAGON 64 in 64 MODE.

Same as above, except the BASIC ROM is moved from 32768
(&H8000) to 49152 (&HC000), which gives a substantial
increase in memory available for program use, but means that
disks cannot be used as the ROM overlays the Cartridge area.
Programs exist to overcome this problem however.

<pre>13824 - 49151 3600 - BFFF PROGRAM USE
49152 - 65279 C000 - FEFF BASIC ROM
65280 - 65375 FF00 - FF5F INPUT/OUTPUT
65376 - 65503 FF60 - FFDF SAM CONTROL BITS
65504 - 65535 FFE0 - FFFF MPU VECTORS</pre>

NOTE

The following pages contain details of the Dragon's memory,
both the Basic work pages and the Basic ROM. While every
effort has been made to ensure the accuracy of these
details, the Editor has had to rely on a number of sources
and it has not been possible to check them all.
Where possible details have also been given of the Tandy
Coco2 equivalent, making it possible for the conversion of
programs from American sources. In so doing you are reminded
that the Coco disk system differs greatly from Dragondos and
is closer to the cassette system in the way that it handles
data files.
One other major difference is the way that graphic binary
files are stored, they are usually 512 bytes higher in
memory than Dragon graphics.

== MEMORY MAP DETAILS ==
<pre>
0 0 BREAK message flag
1 1 STRING delimiting character
2 2 Another delimiting character
3 3 General counter
4 4 Count of IF's seen looking for ELSE
5 5 DIM flag
6 6 VARIABLE type flag 0=numeric 255=string
7 7 Garbage collection flag
8 8 Subscript allowed flag
9 9 INPUT/READ flag
10 A Arithmetic use
11) B) String pointer - first free temporary
12) C)
13) D) String pointer - last used temporory
15-24 E-18 Temporary results
25/26 19/1A Start address of Basic program
27/28 1B/1C Start address of simple variables table
see D User 1/86 p38 for details of
variables.
29/30 1D/1E Start address of ARRAY table
31/32 1F/20 End of storage (last byte used by Basic)
33/34 21/22 Top of Stack. ((Stack grows down)
35/36 23/24 Top of free STRING space. By subtracting the
contents of 33/34 you get free string space
37/38 25/26 Pointer to STRING in string space
39/40 27/28 Top of RAM available to Basic
41/42 29/2A Line number used in 'CONT' command
43/44 2B/2C Temp G.P. line number store
45/46 2D/2E Pointer to statement to be executed
47/48 2F/30 Direct mode command text pointer
49/50 31/32 Current DATA statement line number
51/52 33/34 Address of next item in current data sta'nt
53/54 35/36 Address of keyboard input buffer
55/56 37/38 Pointer to VARIABLE last in use
57/58 39/3A VARPTR address of variable last in use
59/78 3B/4E Evaluation variables
65/66 41/42 High end destination address for block move
67/68 43/44 High end origin address
69/70 45/46 Low end destination address
71/72 47/48 Low end origin address
79/84 4F/54 Floating Point Accumulator: No 1
79 4F Exponent )
80/83 50/53 Mantissa ) Details of FPA
84 54 Sign )
85 55 Temporary sign of FAC
86 56 String variable length
92/97 5C/61 Floating Pt Acc No 2: details as before
98 62 Sign comparison
99 63 Extended precision byte-Coco
104/105 68/69 Current line number (65535 in direct mode)
106 6A VDU Comma field width (default 16)
107 6B VDU Last Comma field (screen width - above)
108 6C VDU Current column number (0 - 31)
109 6D VDU Line width. No of characters per line
110 6E Cassette I/O flag. Set FF on input incurring
111 6F DEVN: re text output: 0=VDU 255=tape 254=prt
112 70 Cassette EOF flag: EOF reached if non zero
113 71 Restart flag. If<>$55 - cold start on reset
114/115 72/73 Restart vector. If flag=$55 & vector points
points to a NOP then warm start else
a cold start.
116/117 74/75 Physical end of RAM
120 78 Cassette status:0=closed 1=input 2=output
121 79 I/O buffer size
122/3 7A/B Header buffer address:where f'name block is
124 7C Cassette block type:
0=f'name block 1=data block 255=EOF marker b
125 7D BLKLEN:Cass Block length:Bytes to read/write
126/7 7E/F Cassette I/O buffer address
128 80 Used internally to calculate the checksum
129 81 I/O error code 1=CRC 2=attempt load into RAM
130/2 82/4 Temp store used by COS
133 85 Last sine value
134 86 Data for Lo-res SET/RESET routine
135 87 ASCII code of last key pressed
136/7 88/89 Current VDU cursor address (ie screen pos)
138/9 8A/B G.P. (16 bit) scratch pad
140 8C Sound pitch value (frequency)
141/2 8D/E GP Countdown facility (?duration of sound)
143 8F Cursor Flash Counter
144/5 90/1 Cassette leader byte count (number of &H55s)
146 92 Min Cycle width of 1200HZ - Init=12
147 93 Min Pulse width of 1200HZ - Init=0A
148 94 Max pulse width of 1200HZ - Init=12
149/50 95/6 Dragon - Motor on delay
Coco - Serial printer Baud rate constant
HEX Msb Lsb (decimal) Baud
149 150
02EB 2 235 75
01CA 1 202 120
0173 1 115 150
00BE 0 180 300
0057 0 87 600 (default)
0028 0 41 1200
0012 0 18 2400
0006 0 6 4800
0001 0 1 9600
151/2 97/8 Keyboard Scan Delay constant: Init=&H045E
153 99 Printer Comma Field Width: Default 16
154 9A Printer Last Comma Field
155 9B Printer Line Width: Set this to width 80?
156 9C Printer Head Column:same as POS(-2) in basic
157/8 9D/E Exec Entry address
159/170 9F/AA Self modifying routine which reads next char
166/7 A6/7 Address of current sig byte - next char pntr
171/4 AB/E Used by RND command
175 AF TRON/TROFF flag: Non zero - trace on
176/7 B0/1 Address os start of USR address table
178 B2 Current foreground colour
179 B3 Current Background colour
180 B4 Temp colour in use
181 B5 Byte value for current colour: ie bits set
182 B6 Graphics PMODE number in use.
183/4 B7/8 Address of LAST byte of current graphics
185 B9 Number of bytes per line in current PMODE
186/7 BA/B Address of FIRST byte: current graphics disp
188 BC Start of graphics pages (MSB) defaults to 06
Changed to 0C by Dragondos
189/90 BD/E Current X Cursor position (not available
191/2 BF/C0 Current Y Cursor position (n.a.)
193 C1 Colour Set currently in use
194 C2 Plot/Unplot flag:0=Reset, Non-zero=Set
195/96 C3/4 Current Horizontal Pixel number
197/8 C5/6 Current Vertical Pixel number
199/200 C7/C8 Current X cursor co-ordinate
201/2 C9/CA Current Y cursor co-ordinate
203/4 CB/CC Circle command X co-ordinate
205/6 CD/CE Circle command Y co-ordinate
207/8 CF/D0 RENUMber increment value
209/10 D1/2 RENUMber Start line (original number)
211/2 D3/4 CLOADM: 2's complement load offset value
213/4 D5/6 RENUMber New Start line (new number)
215 D7 Editor line length - not user available
216/221 D8/DD Graphics use
222 DE Current octave in use (0 - 4)
223/4 DF/E0 Volume data for volume setting in PLAY
225 E1 Current note length in PLAY
226 E2 Current TEMPO for PLAY command
227/8 E3/4 Music duration count
229 E5 Music dotted note flag
230 E6 Coco - Baud rate constant
231 E7 Coco - Input timeout constant
232 E8 Current ANGLE used in DRAW routine
233 E9 Current SCALE used in DRAW routine
234 EA Disk operation code-what operation specified
235 EB Disk Drive number(1 - 4) Coco(1 - 3)
236 EC Disk read/write TRACK number
237 ED Disk read/write SECTOR number
238/9 EE/F Disk read/write Sector Buffer address
240 F0 Disk Error Status byte (Convt to DDOS code)
241 F1 Disk File Control Block number (1 - 10)
242 F2 Number of bytes in Disk buffer area
243 F3 No of bytes to transfer to/from buffer
244 F4 Number of SIDES/TRACKS for current drive
00=1 side 40 tracks 01=2 sides 40 tracks
FF=1 side 80 tracks FE=2 sides 80 tracks
The FORMAT of a disk is taken from the last
few bytes of Sector 1 of Track 20 in Drogon
DOS, on first access of disk after switch on
or RESET.
245 F5 File Read/write flag
0=read, 1=write & FF=verify
246 F6 Disk I/O in progress flag
256/8 100/2 SWI3 JUMP VECTOR - called from &HFFF2
Execution of a SWI3 instruction of &H113F
will stack Registers and jump here
259/61 103/5 SWI2 JUMP VECTOR - called from &HFFF4
Execution of a SWI2 instruction of &H103F
will stack registers and jump here
262/4 106/8 SWI1 JUMP VECTOR - called from &HFFFA -&H3F
will stack registers and jump here
265/7 109/B NMI JUMP VECTOR -non-maskable interrupt
called from &HFFFC, set to &H7ED7AE JUMPD7AE
by initialisation of disk operating system
in the Coco. Okay for Dragon?
268/70 10C/E IRQ JUMP SECTOR - Interrupt request called
from &HFFF8. Set to &H7EA9B3 to initialise
Basic, Set to &H7E894C for initialisation of
extended Basic or set to &H7ED7BC for the
initialisation of DOS in the Coco.
271/3 10F/111 FIRQ JUMP VECTOR - Fast interrupt request
called from &HFFF6, set to &H7EA0F6 by the
initialisation of Basic and causes a jump to
the Cartridge Port in the Coco.
274/6 112/4 In Coco this is EXEC of USR basic function
274/5 112/3 Timer - current value of system timer
In both Dragon and Coco (double function)
277/81 115/9 Random number seeds used in RND function
282/7 11A/F Unused in Dragon
282 11A Coco - Caps lock 1=lock 0=unlock (lower case
283/4 11B/C Coco - keyboard delay constant
285/7 11D/F Coco - Vector to 45509 (JUMP $8489)
288 120 Number of Basic commands (reserved words)
289/90 121/2 Address of list of Basic commands
291/2 123/4 Address of Command Despatch Table
293 125 Number of Basic functions
294/5 126/7 Address of list of Basic functions
296/7 128/9 Address of Function Despatch Table
298/307 12A/133 As for 288 to 297, but in Dragon refers to
Disk commands and functions, but in the Coco
to Extended Basic commands and functions.
308/317 134/13D These addresses as above re COCO disks.
308/327 134/147 DRAGON - USR Table (20 bytes 2 each USR)
This USR table is switched to 1667 to 1686,
or Hex 683 to 696 when DOS is connected and
is replaced with Disk Stub3 which acts as a
terminator.
328 148 PRINTER AUTO LF/CR Flag
329 149 Dragon - Caps Lock flag:non zero=upper case
330 14A Number of chars in end of line sequence(1-4)
331/4 14B/E End of Line Characters: Set to CR/LF/NUL/NUL
This sequence is sent to printer when a
carriage return is output.
336/45 150/9 Dragon Keyboard 'Roll-over' table
338/45 152/9 Coco Keyboard 'Roll-over' table
</pre>

DRAGON/COCO KEYBOARD ROLLOVER TABLE
<pre>
Response:
Address 191 223 239 247 251 253 254
Dec Hex D C D C D C D C D C D C D C
338 152 ENT ENT X 8 P 0 H X @ P 8 H 0 @
339 153 CLR CLR Y 9 Q 1 I Y A Q 8 I 1 A
340 154 BRK BRK Z : R 2 J Z B R : J 2 B
341 155 ; S 3 K C S ; K 3 C
342 156 , T 4 L D T , L 4 D
343 157 - U 5 M E U - M 5 E
344 158 . V 6 N F V . N 6 F
345 159 SPC / W 7 O SPC G W / O 7 G
</pre>
RESPONSE IS 255 OR &HFF IF NO KEY IS PRESSED
<pre>
346 15A Right Joystick(0) - X value
347 15B Right Joystick(1) - Y value
348 15C Left Joystick (2) - X value
349 15D Left Joystick (3) - Y value

350 to 424 15E to 1A8 RAM HOOKS (each 3 bytes)
350/2 15E/160 Device Open- called just before OPEN command
353/5 161/3 Device Number-called when a DEVN is verified
356/8 164/6 Device Initialisation- called before setting
up the Device parameters in Loctn 106 to 109
359/61 167/9 OUTPUT CHAR TO DEVN:called just before out-
putting char in A Reg to DEVN
362/4 16A/C INPUT CHAR FROM DEVN: called just before
inputting a char from DEVN into A Register
365/7 16D/F INPUT FILE: called just before inputting a
file using INPUT
368/70 170/2 OUTPUT FILE: called just before outputting
to a file using PRINT
371/3 173/5 CLOSE ALL FILES: called before all files are
closed, action only taken if Cassette open
374/6 176/8 CLOSE FILE: called before device is CLOSED
action only taken if DEVN is -1 (tape)
377/9 179/B COMMAND INTERPRETER: called before interpret
of token in A Reg as command, used by Delta
380/2 17C/E RE-REQUEST INPUT. Called before requesting
more data from keyboard- ie before ?? prompt
383/5 17F/181 CHECK KEYS. Called before keyboard scanned
for BREAK and SHIFT/@. Keyboard not scanned
if DEVN is -1.
386/8 182/4 LINE INPUT FILE. Called before Line Input is
executed on current DEVN
389/91 185/7 CLOSE FILE & COMMAND. Called before closing
an ASCII file just read in as a Basic prog'm
by CLOAD & returning to COMMAND mode.
392/4 188/A CHECK EOF. Called before checking for EOF
for current DEVN
395/7 18B/D EVALUATE EXPRESSION. (obvious)
398/400 18E/190 USER ERROR TRAP. Can be patched by the user,
that is in Basic, to trap error messages.
401/3 191/3 SYSTEM ERROR TRAP. Can be patched by the
'system', ie Basic extension ROMs to trap
errors (used by Dragondos)
404/6 194/6 RUN LINK. Called when RUN command is about
to be executed. Patched by DDOS to allow a
disk filename to be specified.
407/9 197/9 RESET BASIC MEMORY. Called from two routines
in ROM before Basic Memory vectors are
changed, ie by entering or editing lines,
running programs etc.
410/2 19A/C GET NEXT COMMAND. Called before reading in
the next Basic command to be executed while
program is running.
413/5 19D/F ASSIGN STRING VARIABLE. (obvious)
416/8 1A0/2 SCREEN ACCESS. Called before the CLS,GET and
PUT commands are executed.
419/21 1A3/5 TOKENISE LINE. Called before an ASCII line
is tokenised in internal Basic format
422/4 1A6/8 DETOKENISE LINE. Called before a Tokenised
line is converted to ASCII characters
425/464 or 1A9/1D0 STRING BUFFER AREA
465 1D1 Cassette filename length
466/73 1D2/9 Cassette filename to search for/or write out
474/728 or 1DA/2D8 CASSETTE FILE DATA BUFFER
Area of memory used to load filename block &
ASCII data blocks - if this contains a file-
name block then this can be peeked (474-488)
474/81 1DA/1E1 Cassette filename (in buffer)
482 1E2 File type: 0=token basic 1=ASCII 2=binary
483 1E3 ASCII flag: 0=binary, non-zero=ASCII files.
484 1E4 Gap flag: 1=continuous, 255(FF)=gapped files
485/6 1E5/6 Execution address of machine code file
487/8 1E7/8 Load address of ungapped machine code file
729/33 2D9/C Basic line input buffer preamble
734/984 2DD/3D8 Basic line input buffer
985/1002 3D9/EA BUFFER space
1003/20 3EB/3FC Unused
1021/2 3FD/E End of line delay - RS 232 port on D64
1023 3FF D64 RS 232 port Baud rate controller port
1024) 400) TEXT SCREEN
1535) 5FF) Default area.
</pre>
The Coco Buffer areas are slightly different:
733/988 2DD/3DC 255 byte Keyboard buffer
737/827 2E1/33B 90 byte Screen buffer

The Disk Work area is from 1536 to 3071, or &H0600 to &H0BFF
Otherwise if disks are not installed these addresses are in
respect of the first of the Graphic pages, but with the DOS
installed the Graphics page 1 starts at 3072 (&H0C00).

== DRAGONDOS WORK SPACE ==
<pre>
1536 0600 Start of Disk work space or Graphics Page 1
when Disk cartridge not installed
1541 0605 Countdown to Disk motor off: Off when zero
1544 0608 Auto Verify ON/OFF: 0=off else checks sector
1546 060A Current Default drive No. Used when no Drive
number is specified in the command
1549/50 060D/E Auto command line number in use
1551/2 060F/10 Auto command increment value
1553 0611 Program LOAD/RUN flag: 0=Load else Load/RUN
1555 0613 Auto command ON/OFF flag: 0=off else Auto on
1556 0614 Error command ON/OFF flag: 0=off else ERR on
1557/8 0615/6 ERROR trap line number: Basic line error rtn
1559/60 0617/8 ERL: line number of last error
1561 0619 ERR: Error code of last basic error
1562/3 061A/B Address of start of statement in error
1564/9 061C/21 Drive 1 details
1570/5 0622/7 Drive 2 details
1576/81 0628/D Drive 3 details
1582/7 062E/33 Drive 4 details
1588) 0634) Disk Buffers 1 to 4 details, 7 bytes each
1615) 064F)
1616/66 0650/82 Current Drive information
1618/9 0652/3 Start address of program loaded
1620/1 1654/5 Length of program loaded
1622/3 1656/7 Entry (EXEC) address of M/code program
1667/86 1683/96 USR Vector table: relocated from 308-327(dec
1687 to 1706) Disk Drive Parameter table
0697 to 06AA) 4 bytes per parameter - 1 for each drive
1687/90 0697/A On Line Flag: Non zero means dive on line
1691/4 069B/E Current Track, if Drive on line
1695/8 069F/A2 Head Stepping rate: This should only be
changed if slower drives are used.
1699/702
06A3/6 Disk Tracks on each drive
1703/6 06A7/A Disk Sectors per track on each drive
1707/24 06AB/BC Directory Sector status
1725/2034 File Control Blocks: 10 in all: One for each
6BD/7F2 open file: Each FCB 32 bytes long
2035/47 7F3/F Temporary variables
2048/3071 )Disk Buffers: 4 in all, each 256 bytes long
800/BFF)

3072 0C00 Start of Graphic Page 1 when disks in place
otherwise start of Graphic Page 2 for tapes.
</pre>

== BASIC INTERPRETER CODES ==
<pre>
32768 8000 Hardware initialisation
32771 8003 Software initialisation
32774 8006 POLCAT:Keyboard input:put into Register A
32777 8009 Cursor Blink
32780 800C CHROUT:Write character in Reg A to screen
32783 800F Writes out character in Reg A to printer
32786 8012 Joystick input:stored in addresses 346/9 dec
32789 8015 Cassette on
32792 8018 Cassette off
32795 801B Write leader to cassette (or A00C)
32798 801E Output byte from Reg A to cassette
32801 8021 CSRDON:Cassette on, prepare for reading
32804 8024 Input one byte from cassette to Register A
32807 8027 Gets one bit in from cassette into carry
32810 802A Reads in a byte from another computer
32813 802D Sends a byte to another computer
32816 8030 Select Baud rate of communications line
</pre>
From here on the Coco equivalents are given in brackets and
only a few Hex addresses will be given
<pre>
33604 (44102) SYSERR: Generates appropriate action for
Error code in B Reg
33649 (44147) CMDMODE: prints OK prompt & returns to the
command mode
33773 (44271) BASVECT2: complete initialisation process
after Basic program loaded
33815 (44313) NEW Basic:removes current Basic program from
memory, resets stack & clears variables
33823 (44321) BASVECT1: Sets up various necessary vectors,
once a Basic program has been loaded
33844 (44339) RESETS STACK: Resets stack to initial position
all entries are lost
33951 (44446) RUN BASIC: runs a basic program in memory,
used to AUTORUN programs
34091 851B (44539) WAIT KEY: waits for a key press, and
when key pressed puts it in A Register
34935 (45382) GET EXPR: routine will evaluate & put VARPTR
address of following expression into 82/83
34951 (45398) GET STRG: compiles a string and puts it into
free string space
35236 (45671) CKCLBRAK: as for CKCOMA, but checks for a
closed bracket
35239 (45674) CKOPBRAK: as for above, but checks for an
open bracket
35242 (45677) CKCOMA: Checks to see next significant char
in command line is a comma, and if not it
produces a SYNTAX error
35244 (45679) CKCHAR: as for CKCOMA, but checks for char
in B Register
35476 (45911) GETVAR: Get VARPTR address of the follwing
variable's name
35625 (46057) GETUSR: Returns value of the argument in the
USR function as 16 bit number in D register
35632 INTCNV: pass parameters to M/code routine
35641 GIVABF:used to pass values from M/C to Basic
35893 (46322) ASSIGN-16-BIT:assigns value in D Register to
a numeric variable
35894 (46323) ASSIGN-8-BIT:assigns value in B register to
a numeric variable
36055 (46481) GARBAGE COLLECT: forces a controlled garbage
collection of string space
36255 (46681) DELVAR: frees space taken by a variable
36433 (46859) GET-8-BIT: returns value of the following
number in B Register
36483 (46909) GET-16-BIT: returns value of the following
number in X register
36522 (46948) LIST BASIC: lists basic program in memory to
to DEVN (device specified)
37025 90A1 (47448) PRINT CR/LE: moves cursor position
to start of a new line
37093 90E5 (47516) OUT STRING:Outputs a text string to
device number in DEVN
38266 957A (48588) PRINT NUMBER:outputs 16 bit number
in D Reg to DEVN
38798 978E RANDOM NUMBER: Generates an 8 bit random
number and puts it in location 278
39998 (34830) ASSIGN-16-BITB:alternative to 35893, assigns
value in Locs 82/83 to a variable
41194 A0EA (36038) WAIT WITH CURSOR:scans keyboard for
a keypress, flashing cursor at print pos.
43207 (38201) CLEAR GRAPHICS:clears current graphics
screen to data in B Register on entry
43304 (38298) SET COLOURS: sets up locations 180 & 181
43320 (38314) SELECT DISPLAY: Selects text or graphics
depending on Z condition code, if Z=1 text
43322 95AC (38316) RESET VDU: resets default VDU mode
43401 (38395) SET VDG MODE:sets VDG in mode given in A Reg
43421 (38415) SET VDG OFFSET: sets display offset for the
graphics mode
43428 (38422) SELECT VDG COL: selects required VDG colour
set from the data in location 193
43489 (38483) SELECT PAGE: on entry B reg contains page no
43536 (38530) SELECT COL SET: selects colour set 0 or 1,
according to data in B reg
43555 (38549) RESERVE HRG RAM: reserves RAM for graphics
and moves basic if necessary
44698 (39639) PLAY NOTE: A Reg contains ASC code of note,
other parameters should be set up
45137 (40118) DRAW:allows access to all facilities of DRAW
46004 (40999) RESET:resets whole works, as if reset button
has been pressed
46080 (41142) BOOT BASIC: restarts the Basic interpreter
as if on power up or reset
46410 B54A (41602) OUTCHAR:outputs character in A Reg
to device number in DEVN (location 111)
46687 (42029) CLOSE FILES: closes any open tape stream and
flushes buffer
46757 (42089) WRITE BASIC: writes current basic program to
cassette
46920 (42257) READ BINARY: reads in BIN file from tape
47283 (42625) FIND FILE: searches tape for matching filename
47411 (42753) READ 1ST BLOCK:gets filename block into tape
buffer
47422 B93E (42763) BLKIN: reads a block of data into
cassette buffer
47505 (42981) WRITE 1ST BLOCK: (obvious)
47513 B999 (42996) BLKOUT: write block of data to tape
47583 (43149) SET LRG LEVEL:on entry the X Reg contains
Lo-res screen address, B Reg colour & loc184
the OR data
47623 (43189) RESET LRG PIXEL:as above but B Reg ignored,
Pixel reset to Black
47656 (43225) CALC PIXEL POS:on entry the top of stack
must contain Lo-res vertical co-ordinate,
preceded by horizontal co-ordinate
47735 BA77 (43304) CLEAR SCREEN: clears screen to space
and 'homes' cursor
47737 BA79 (43306) CLEAR SCREEN to CHR: clears screen
to character in B Reg
47776 (43345) BEEP:sound Beep for length held in B Reg and
pitch set by location 140
47811 (43380) AUDIO OFF: disables sound:clears bit 3 65315
47813 (43382) ENABLE SOUND: enables 6 bit sound by setting
Bit 3 of 65315
47828 (43397) RESET D/A: Puts value $7E into D/A converter
address
47830 (43399) WRITE D/A: puts contents of A Reg into D/A C
47852 (43421) AUDIO ON:on entry the B Reg must be zero
48000 BB80 BOOT BASIC64K: Boots 64 mode
48053 BBB5 (41369) UPDATE CURSOR: flashes cursor
48101 BBE5 (41409) POLCAT: scans keyboard and puts the
character in A Register
48288 BCA0 (41763) CLEAR VDU LINE: clears current VDU
line from the cursor position
48299 BCAB (41738) VDU OUT: prints char in A Reg to VDU
48373 BCF5 PRINTER DIR OUT: char in A Reg sent printer
48394 BD0A PCRLF:moves print head to start of next line
48410 BD1A (41663) PRINTER OUT:Char in Reg A to printer
48449 (43426) SELECT JSK:selects joystick sources (ports -
0 - 3) from A Register
48466 BD52 (43486) READ JSKS: Updates all joystick data
locations (346/9)
48549 BDA5 (42837) BIT IN:reads a single bit(see below)
48557 BDAD (42825) BYTE IN:reads a byte into A Reg(tape
48591 (42954) MOTOR ON: tape - sets bit 3 of $FF21
48604 (42987) MOTOR OFF: tape - clears bit 3 of $FF21
48615 (42876) READ LEADER: motor on & prepares COS to read
48658 (43050) BYTE OUT: writes byte in A Reg to tape
48746 BE6A WRTLDR:turns cassette on and writes a leader
</pre>
THE FOLLOWING ARE DRAGONDOS ROUTINES
<pre>
49166 C00E LENFIL: Report file length
49168 C010 CLOSAL: Close all files
49176 C018 GETFRE: Get free space
49178 C01A DELETE: Delete a file
49180 C01C PROTECT/UNPROTECT a file
49182 C01E RENAME a file
49184 C020 GETDIR: Get directory entry
49406 C0FC WRITE SECTOR: Writes 256 bytes to disk
49412 C104 READ SECTOR: reads 256 bytes from disk
49509 C165 DRIVE INIT: initialises DOS hardware
49513 C169 HARDWARE I/O: low level command to hardware
50108 C3BC FORMAT DISK: in the DEFD drive
53581 D14D GET FREE SPACE: free bytes on current drive
54033 D311 CONVERT SECTOR:converts LSN(Logical sect no)
in Y Reg to Track/Sector
55868 DA3C DIR DSK: directory of disk in DEFD drive to
DEVN
56229 DBA5 BEEP: on entry B Reg should contain number
of beeps
56267 DBCB WAIT TIME:on entry X Reg should contain the
number of milliseconds to wait
56330 DC0A BOOT DSK: boots an OS off disk in DEFD drive
</pre>

== INPUT/OUTPUT ADDRESSES ==
{| class="wikitable"
|-
! scope="col"| Addr
! scope="col"| Device
! scope="col"| Comments and references
! scope="col"| Bit by bit
|-
| FEFF
| [[RACE Computer Expansion Cage]]
| Bits 0-1 : slot selection
|-
| FF00
|
* Dragon 32
* Dragon 64
| PIA 0 side A data register ([https://www.lomont.org/software/misc/coco/Lomont_CoCoHardware.pdf] p.48, [http://www.dragondata.co.uk/Publications/InsideTheDragon.pdf] p.196)
|
* Bit 0 right joystick button
* Bit 1 left joystick button
* Bits 0 to 6 Keyboard row input
* Bit 7 joystick comparator input
|-
| FF01
|
* Dragon 32
* Dragon 64
| PIA 0 side A control register ([https://www.lomont.org/software/misc/coco/Lomont_CoCoHardware.pdf] p.48)
|
|-
| FF02
|
* Dragon 32
* Dragon 64
| PIA 0 side B data register ([https://www.lomont.org/software/misc/coco/Lomont_CoCoHardware.pdf] p.48)
| Bits 0 to 7: keyboard column output
|-
| FF03
|
* Dragon 32
* Dragon 64
| PIA 0 side B control register ([https://www.lomont.org/software/misc/coco/Lomont_CoCoHardware.pdf] p.48)
|
|-
| FF04-FF07
|
* Dragon 64
* Dragon Alpha
| ACIA
|
|-
| FF20
|
* Dragon 32
* Dragon 64
| PIA 1 side A data register ([https://www.lomont.org/software/misc/coco/Lomont_CoCoHardware.pdf] p.48)
|
* Bit 0 - cassette data input
* Bit 1 - RS232 data output
* Bits 2-7 : 6 bit D/A(.25 to 4.75 volts out)
|-
| FF21
|
* Dragon 32
* Dragon 64
| PIA 1 side A control register ([https://www.lomont.org/software/misc/coco/Lomont_CoCoHardware.pdf] p.48)
|
* Bit 0 - control of CD : 0=FIRQ to CPU disabled, 1=enabled
* Bit 1 - RS 232 status input - 0=set flag falling edge CD, 1=rising edge
* Bit 2 - normal Data Direction Register addsd - 0=change FF20 to DDR
* Bit 3 - Cass Motor control, 0=off, 1=on
* Bit 4,5 - always 1
* Bit 6 - not used
* Bit 7 - CD interrupt flag
|-
| FF22
|
* Dragon 32
* Dragon 64
| PIA 1 side B data register ([https://www.lomont.org/software/misc/coco/Lomont_CoCoHardware.pdf] p.48)
|
* Bit 0 - RS 232 data input
* Bit 1 - single bit cound output
* Bit 2 - RAM size input
* Bit 3 - VDG Control Output CSS(color set ct)
* Bit 4 - VDG Control Output GM0&NOT(INT)/EXT
* Bit 5 - VDG Cont Output GM1
* Bit 6 - VDG Cont Output GM2
* Bit 7 - VDG Cont Output NOT(A)/G
|-
| FF23
|
* Dragon 32
* Dragon 64
| PIA 1 side B control register ([https://www.lomont.org/software/misc/coco/Lomont_CoCoHardware.pdf] p.48)
|
* Bit 0 - control of cartridge, 0=FIRQ to CPU disabled, 1= enabled
* Bit 1 - Interrupt input, 0=sets flag on falling edge of cartridge, 1=sets flag on rising edge of cartridge
* Bit 2 - Normally 1, 0=changes FF22 to DDReg
* Bit 3 - 6 bit sound enable
* Bits 4,5 - always 1
* Bit 6 - not used
* Bit 7 - cartridge interrupt flag
|-
| FF24-FF27
| Dragon Alpha
|
| Dragon Alpha PIA
|-
| FF28
| Dragon Alpha
|
| Dragon Alpha 6850 Modem Port
|-
| FF2C-FF2F
| Dragon Alpha
|
| Dragon Alpha Floppy Disk Controller
|-
| FF40-FF5F
| [[Dragon I/O Cartridge (Rink)]]
| To control which output pins are high and which are low, you write a single byte to any address between 0xFF40 and 0xFF5F.
|
|-
| FF40-FF43 (mirrored upto FF5F)
| Voltmace Delta 14B multi-button joystick adapter
| 6821 PIA [http://archive.worldofdragon.org/phpBB3/viewtopic.php?f=9&p=23906#p23906]
|
|-
| FF40-FF44 (?)
| [[Delta DOS]]
| (from a quick disassembly of Delta DOS ROM)
|
|-
| FF40
|
* Dragon FDC
* Coco FDC
* CocoSDC
| Command/status register
|
|-
| FF41
|
* Dragon FDC
* Coco FDC
* CocoSDC
* Becker Port (DriveWire)
| Track register
|
|-
| FF42-FF43
| [[Dragon Speech Synthesis|JCB Microsystems' Dragon Speech Synthesis]]
| PIA data and control registers ([https://archive.worldofdragon.org/browse/downloads/Software/Dragon/J.C.B%20Microsystems/Dragon%2032%20Speech%20Synthesis/JCB%20Speech%20Synthesis%20Module%20User%20Manual.pdf])
|
|-
| FF42
|
* Dragon FDC
* Coco FDC
* CocoSDC
* Becker Port (DriveWire)
| Sector register
|
|-
| FF43
|
* Dragon FDC
* Coco FDC
* CocoSDC
| Floppy data register
|
|-
| FF48
|
* Dragon FDC
* Coco FDC
| Disk controller latch
|
|-
| FF49
| [http://www.cloud9tech.com/ Cloud-9] Coco miniFlash
| Flash bank selection register (selectable between FF49, FF59, FF69, FF79) [https://archive.worldofdragon.org/phpBB3/viewtopic.php?f=9&t=10938]
|
|-
| FF4A
| CocoSDC
| Flash Data Register
|
|-
| FF4A
| CocoSDC
| Flash Control Register
|
|-
| FF4C-FF4F (mirrors once at FF5C-FF5F)
| Ikon Drive
| [http://archive.worldofdragon.org/phpBB3/viewtopic.php?f=9&p=23906#p23906]
|

|-
| FF50
| [[DragonMMC SDCard|DragonMMC]]
| Dragon D CMD_REG Command/Result ( [https://github.com/prime6809/DragonMMC/blob/master/DragonFirmware/defs/mmc2def.asm], [https://github.com/prime6809/DragonMMC/blob/master/DragonFirmware/defs/mmc2def.asm])
|
|-
| FF50
| [https://colorcomputerarchive.com/repo/Documents/Manuals/Hardware/CoCo%20XT%20Hard%20Disk%20Interface%20v2.4%20(Burke%20&%20Burke).pdf Burke & Burke Coco-XT]
| MFM disk controller - HDDATA - data transfer byte (read/write)
|
|-
| FF51
| [[DragonMMC SDCard|DragonMMC]]
| Dragon MMC D_LATCH_REG - single byte parameters ( [https://github.com/prime6809/DragonMMC/blob/master/DragonFirmware/defs/mmc2def.asm], [https://github.com/prime6809/DragonMMC/blob/master/DragonFirmware/defs/mmc2def.asm])
|
|-
| FF51
| [https://colorcomputerarchive.com/repo/Documents/Manuals/Hardware/CoCo%20XT%20Hard%20Disk%20Interface%20v2.4%20(Burke%20&%20Burke).pdf Burke & Burke Coco-XT]
| MFM disk controller: read HDSTAT status, write HDRSET reset
|
|-
| FF52
| [[DragonMMC SDCard|DragonMMC]]
| Dragon MMC D_READ_DATA_REG ( [https://github.com/prime6809/DragonMMC/blob/master/DragonFirmware/defs/mmc2def.asm], [https://github.com/prime6809/DragonMMC/blob/master/DragonFirmware/defs/mmc2def.asm])
|
|-
| FF52
| [https://colorcomputerarchive.com/repo/Documents/Manuals/Hardware/CoCo%20XT%20Hard%20Disk%20Interface%20v2.4%20(Burke%20&%20Burke).pdf Burke & Burke Coco-XT]
| MFM disk controller: write HDATTN ; get attention of controller
|
|-
| FF53
| [[DragonMMC SDCard|DragonMMC]]
| Dragon MMC D_WRITE_DATA_REG ( [https://github.com/prime6809/DragonMMC/blob/master/DragonFirmware/defs/mmc2def.asm], [https://github.com/prime6809/DragonMMC/blob/master/DragonFirmware/defs/mmc2def.asm])
|
|-
| FF53
| [https://colorcomputerarchive.com/repo/Documents/Manuals/Hardware/CoCo%20XT%20Hard%20Disk%20Interface%20v2.4%20(Burke%20&%20Burke).pdf Burke & Burke Coco-XT]
| MFM disk controller: write HDMASK ; controller dma and interrupts (not used on coco or dragon)
|
|-
| FF54
| [[DragonMMC SDCard|DragonMMC]]
| Dragon MMC D_STATUS_REG AVR status ( [https://archive.worldofdragon.org/phpBB3/viewtopic.php?f=9&t=10938])
|
|-
| FF55
| [[DragonMMC SDCard|DragonMMC]]
| Dragon MMC D_PIA_MAP PIA redirect (write only) ( [https://archive.worldofdragon.org/phpBB3/viewtopic.php?f=9&t=10938])
|
|-
| FF56
| [[DragonMMC SDCard|DragonMMC]]
| Dragon D_RAM_CTRL RAM / ROM control register ( [https://archive.worldofdragon.org/phpBB3/viewtopic.php?f=9&t=10938])
|
|-
| FF56-FF57
| Dragon-MSX2+ (in MPI mode)
| YM2413 ports ([http://archive.worldofdragon.org/phpBB3/viewtopic.php?f=9&p=23906#p23906])
|
|-
| FF58
| [[DragonMMC SDCard|DragonMMC]]
| D_SAMBITS_MSB (16 bits as programmed to SAM) ( [https://archive.worldofdragon.org/phpBB3/viewtopic.php?f=9&t=10938])
|
|-
| FF59
| [[DragonMMC SDCard|DragonMMC]]
| D_SAMBITS_LSB (16 bits as programmed to SAM) ( [https://archive.worldofdragon.org/phpBB3/viewtopic.php?f=9&t=10938])
|
|-
| FF58-FF5B
| Dragon-MSX2+ (in MPI mode)
| V9958 ports
|
|-
| FF59
| [http://www.cloud9tech.com/ Cloud-9] Coco miniFlash
| Flash bank selection register (selectable between FF49, FF59, FF69, FF79) [https://archive.worldofdragon.org/phpBB3/viewtopic.php?f=9&t=10938]
|
|-
| FF5A-FF5B
| [[DragonMMC SDCard|DragonMMC]]
| RAM bank read / write registers ( [https://archive.worldofdragon.org/phpBB3/viewtopic.php?f=9&t=10938])
|
|-
| FF5C-FF5F
| [[Touchmaster Tablet]]
| PIA ( [http://archive.worldofdragon.org/index.php?title=File:Touchmaster_UserGuide_09.jpg])
|
|-
| FF5C-FF5D
| Dragon-MSX2+ (in MPI mode)
| YM2149 ports
|
|-
| FF5E
| Dragon-MSX2+ (in MPI mode)
| Video select port
| Only bit 0
|-
| FF69
| [http://www.cloud9tech.com/ Cloud-9] Coco miniFlash
| Flash bank selection register (selectable between FF49, FF59, FF69, FF79) [https://archive.worldofdragon.org/phpBB3/viewtopic.php?f=9&t=10938]
|
|-
| FF76-FF77
| Dragon-MSX2+ (in native mode)
| YM2413 ports ([http://archive.worldofdragon.org/phpBB3/viewtopic.php?f=9&p=23906#p23906])
|
|-
| FF78-FF7B
| Dragon-MSX2+ (in native mode)
| V9958 ports
|
|-
| FF79
| [http://www.cloud9tech.com/ Cloud-9] Coco miniFlash
| Flash bank selection register (selectable between FF49, FF59, FF69, FF79) [https://archive.worldofdragon.org/phpBB3/viewtopic.php?f=9&t=10938]
|
|-
| FF7A-FF7B
| [[Orchestra 90]]
|
|
|-
| FF7C-FF7D
| Dragon-MSX2+ (in native mode)
| YM2149 ports
|
|-
| FF7E
| Dragon-MSX2+ (in native mode)
| Video select port
| Only bit 0
|-
| FF7F
|
* MPI
* Mega-Mini MPI
| MPI (and clones) slot selection ([https://www.lomont.org/software/misc/coco/Lomont_CoCoHardware.pdf], p.59 )
|
* Bits 5-4: # of active CTS slot (ROM)
* Bits 1-0: # of active SCS slot (Floppy Disk Controller)
|-
| FF80-FF8F
| [[The Dragon's Claw]] - default addresses
| Rockwell 6522 VIA - 16 registers, base address can be changed to FF90, FFA0 or FFB0 with a wire link
|
|-
| FF90-FF9F
| [[The Dragon's Claw]] - alternate addresses
| Rockwell 6522 VIA - 16 registers, base address can be changed to FF90, FFA0 or FFB0 with a wire link
|
|-
| FF90-91
| MooH
|
|
|-
| FFA0-FFAF
| [[The Dragon's Claw]] - alternate addresses
| Rockwell 6522 VIA - 16 registers, base address can be changed to FF90, FFA0 or FFB0 with a wire link
|
|-
| FFA0-FFAF
| MooH
|
|
|-
| FFB0-FFBF
| [[The Dragon's Claw]] - alternate addresses
| Rockwell 6522 VIA - 16 registers, base address can be changed to FF90, FFA0 or FFB0 with a wire link
|
|-
| FFC0-FFD9
| All Dragons
| SAM Control bits (see below)
|
|-
| FFE0
| Compusense [[Dragon Plus]]
| 6845 control register ([https://archive.worldofdragon.org/phpBB3/download/file.php?id=4675])
|
|-
| FFE1
| Compusense [[Dragon Plus]]
| 6845 data register
|
|-
| FFE2
| Compusense [[Dragon Plus]]
| Memory bank register & status of 6845 display
|
* Bits 1-2 : select 32K bank (00 = standard lower 32K ; 01= bank A ; 11 = bank B)
* Read bit 0 : 0=video display available (i.e. blanking) / 1=video display not available (not blanking)
* Write bit 0: 1=select video RAM in the lower 2K
|}

== SAM CONTROL BITS ==
<pre>
65472/7 FFC0/5 VDG Control Registers for 6883 SAM
Contains 3 pairs of addresses (V0-V2), and
poking any value to EVEN addresses sets Bit
Off(0) in VDG circuitry. Poking value to ODD
addresses set Bit ON(1) in 6847 VDG circuit
65472/3 FFC0/1 Control of Bit 0 (V0)
65474/5 FFC2/3 1 (V1)
65476/7 FFC4/5 2 (V2)
65478/91 Page Select Register contains 7 pairs of
FFC6/D3 (F0-F6) control Display Start address (Bin)
Address os upper left most display element=
0000+1/2*OFFSET. Poking any value to even
addresses sets Bit OFF (0) in Page select.
Poking any value to ODD addresses sets Bit
ON(1) in Page Select Circuitry.
Also BASEPAGE is set by converting binary
value of F (Bits F0 to F6) to decimal and
multiplying this decimal number by 512.
65478/9 FFC6/7 Control of Bit 0 (F0)
65480/1 FFC8/9 1 (F1)
65482/3 FFCA/B 2 (F2)
65484/5 FFCC/D 3 (F3)
65486/7 FFCE/F 4 (F4)
65488/9 FFD0/1 5 (F5)
65490/1 FFD2/3 6 (F6)

65492/3 FFD4/5 Page #1 P1 control of Bit 7: (F7) 0=Normal
65494/7 FFD6/9 Clock Speed (R0-R1) Poking any value to even
addresses sets Bit OFF (0). Poking any value
to ODD addresses sets bit ON (1).
65494/5 FFD6/7 Control of Bit R0
65496/7 FFD8/9 Control of Bit R1
R0=0, R1=0 (slow mode defa
</pre>

== MPU VECTORS ==

<pre>
65522/3 FFF2/3 SWI 3 Vector mapped to 49138/9 BFF2/3
65524/5 FFF4/5 SWI 2 vector 49140/1 BFF4/5
65526/7 FFF6/7 FIRQ vector 49142/3 BFF6/7
65528/9 FFF8/9 IRQ vector 49144/5 BFF8/9
65530/1 FFFA/B SWI 1 vector 49146/7 BFFA/B
65532/3 FFFC/D NMI vector 49148/9 BFFC/D
65534/5 FFFE/F RESET vector 49150/1 BFFE/F
</pre>

Tape\Disk Preservation

2021-09-29T21:31:40Z

Polluks: /* BAS CAS WAV */

(Community info on how to preserve existing tape and disk software - conversion from native Dragon to PC formats - WAV, CAS, VDK, DMK, conversion between formats and restoration back to physical media)

== Tools ==

=== WAV/VOC to CAS ===

'''XROAR'''

Currently the preferred method is the XROAR emulator, this can be using to output the byte stream that its virtual ADC reads from a WAV file as the tape loads (CLOAD/CLOADM). Because this method is using an emulated ADC and the actual Dragon ROM routines to read the "tape" the success ratio for conversion is much higher.

'''Dragon Convert for Windows (DCWIN)'''

DCWIN is a Windows application that can perform conversions of 8-bit WAV files to CAS format for use with emulators. Its method and style of operation is broadly similar to DC (see below) together with additional options and enhancements for preserving and restoring leaders. It has a graphical user interface and requires the .NET framework version 3.5 (which is supplied with Windows 7 and can also be installed on Windows XP, Windows Vista and Windows Server 2003/2008).

'''Dragon Convert (DC)'''

Dragon Convert (DC) is the original tool for converting Dragon and Coco cassette data between a range of different file formats.
It's designed for MS-DOS and has always been packaged with the PC-Dragon emulator series. The following notes are taken from the supplied ''Reference Manual''...

Where the input to Dragon Convert is a WAV or VOC file the audio information is scanned for Dragon cassette data and converted to a virtual cassette file. The output filename is derived from the Dragon filename rather than the input filename.

During conversion Dragon Convert displays a counter to show the progress in converting the files. If the cassette programs conform to the conventional Dragon cassette format then the filenames and load/execution addresses of binary files are listed as the programs are encountered. All of the files contained in a single input file will be placed in a single output file.

If Dragon Convert detects a loading error in the WAV or VOC file then you are given the option to abort the conversion, retry a block, or proceed with the conversion ignoring the error. If you choose to ignore errors then the converted file is unlikely to be usable, although several programs do exist which deliberately contain errors.

If you choose to retry a block then the current conversion parameters (see below) appear so that different parameters may be entered. Type the new values at the prompt or press RETURN to leave a parameter unchanged. Dragon Convert then attempts to load the block using the new parameter values. There is, of course, no advantage to be gained by retrying a block without adjusting either of the parameters.

Dragon Convert will normally assume that the sampled file begins with a leader, and will initially seek the leader to synchronise with the data. In cases where a leader is not present this may cause data to be missed. To avoid this give the /L option on the command line to disable the feature.

Although Dragon Convert is designed to work with data in the conventional Dragon cassette format it may also be used with cassettes which use a proprietary format. For such programs specify /R on the command line and Dragon Convert will scan the input as a raw bit stream. This results in a file called CASSETTE.CAS. When Dragon Convert is used with this option the display shows only the number of bytes converted and loading errors cannot be reported.

The following actions may be taken if you suffer from loading errors:

* Use the highest available sampling rate for your sound card. At least 22KHz is required.

* The amplitude of the input data should comfortably span the available range. Increase the input volume if necessary.

* It is a good idea to clean up the wave form before presenting it for conversion. Try cutting any white space before the first program block and omitting any noisy parts of the leaders.

* MS-Windows software (Eg. Creative Wave Studio) usually produces better results than MS-DOS based software.

* The wavelength amplitude threshold may be specified on the command line using the /Wn option. For a 44KHz sample a threshold of 29 to 31 is usually correct. For 22KHz files the value of n should be in the range 12 to 15.

* The relative volume of the wave form may be specified using the /Sn command line option, where 0 < n < 126.

You can abort the operation of Dragon Convert in the middle of a conversion by pressing the CTRL key.

=== CAS to WAV ===

'''Dragon Convert for Windows (DCWIN)'''

DCWIN can be used to convert cassette files to WAV format in a similar way to DC (see below). The size of file that can be converted is limited only by the available memory to buffer the WAV file (unlike the MS-DOS version which cannot be used for CAS files of 64KB or greater).

'''Dragon Convert (DC)'''

A secondary use of Dragon Convert (DC.EXE) is to convert cassette files back to digital audio format so that they can be written to cassette and loaded into a real machine. When converting to audio format the cassette file is not examined thereby enabling any file type or proprietary format to be converted. To use Dragon Convert for this purpose simply specify the filename of a cassette file when you start the program.

By default a 44KHz WAV file will result. This gives very high quality playback but requires more than 8Mb of hard disk space for a 32K Dragon file. You can therefore optionally specify /22 on the command line to request a 22KHz output file (or /11 for 11KHz).

If the CAS file has sufficient SYNC bytes (see CAS Format below) then the resultant WAV can be loaded by a real Dragon 32/64. Some of the older CAS files with truncated SYNC bytes can be rescued using the FIXCAS.EXE tool that attempts to insert the appropriate number of missing SYNC bytes into the CAS file.

=== BAS ↔ CAS ↔ WAV ===

'''PyDC - Python Dragon 32 converter'''

PyDC is a OpenSource (GPL) Python script to convert between .bas ↔ .cas ↔ .wav in every variation.

More information here: https://github.com/jedie/PyDragon32/tree/master/PyDC

=== CAS -> BAS ===

Quick tool for converting Dragon CAS format to readable text of basic listing:

https://bitbucket.org/jimbro1000/cas2bas/src/master/

=== Disk to VDK ===

Using and old PC with a 5.25 inch drive and a DOS environment, the VCOPY.EXE tool can be used to copy some common Dragon disk formats to .VDK files.

'''Making DragonDos disk images under Linux'''

This will allow you to make RAW images of DragonDos disks, you will need to add/remove the VDK header to allow them to be used with an emulator. For most of this you will need to be logged in as root. Firstly you need to add the following lines to the end of your /etc/fdprm

DragonDos 40 track disk in 80 track drive (eg 1.2M). for 40 track in 40 track drive, set the 6th column to 0 instead of 1 (like the 80 track formats below !).

ddosSS40 360 9 1 40 1 0x2A 0x39 0xDF 0x50

ddosDS40 720 9 2 40 1 0x2A 0x39 0xDF 0x50

DragonDos 80 track disks in an 80 track drive (eg 720K,1.2M,1.44M)

ddosSS80 720 9 1 80 0 0x2A 0x39 0xDF 0x50

ddosDS80 1440 9 2 80 0 0x2A 0x39 0xDF 0x50

Then change to the directory that you want to create the image in and type :- setfdprm /dev/fd0 ddosSS40
Replace /dev/fd0 with the name of the floppy drive you are using, and ddosSS40 with the name of the format you want to use in this case a single sided 40 track disk.

'''IMPORTANT'''

The parameters set by setfdprm must be set AFTER the disk has been inserted into the drive, and will need to be set FOR EACH subsiquent disk, don't say you have not been warned :)

To actually create the image type :- dd if=/dev/fd0 count=360 of=dragon.img
Replace /dev/fd0 with the name of the floppy you are using, and dragon.img with the name of the file you want to create. Count, should be replaced with the first number after the disk type (second column), from /etc/fdprm, this is the size of the disk in 512 byte blocks.

You can also write a raw disk image to a preformatted DragonDos disk with :- dd if=dragon.img count=360 of=/dev/fd0
Parameters as described above in reading the disks.

You will then need to add/remove the VDK header - a set of tools is available to help.

=== Disk to JVC ===

Linux - dd

=== JVC to VDK ===

Perl Tool to add VDK header

=== VDK to JVC ===

Perl Tool to remove VDK header

=== VDK to Disk ===

Using and old PC with a 5.25 inch drive and a DOS environment, the VCOPY.EXE tool can be used to copy some common Dragon disk formats from .VDK files to disks. The disks must have been formatted in a real Dragon first....

=== JVC to Disk ===

Linux - dd

=== Dumping ROMS ===

The PC-Dragon ''Reference Manual'' provides the following advice for dumping ROMs...

There are several ways to transfer your ROM for use with Dragon emulators. The method suggested here is to use the Dragon Convert utility to transfer the ROM in the same way as cassettes. An alternative method would be to place the ROM in an EEPROM reader connected to a PC and dump the contents to a file.

The procedure for transfer via cassette and the Dragon Convert utility is as follows:

1) Boot up your Dragon 32, Dragon 64 or Tandy CoCo.

2) Ready your tape recorder for recording and commit the ROM to
cassette by typing:

CSAVEM "DRAGROM", &H8000, &HBFFF, 0

If you have a Tandy CoCo you may optionally use the name TANDYROM
rather than DRAGROM.

3) Boot up your PC and SoundBlaster Pro wave form editor software.
Sample the cassette recorded in step 2 into a file. Alternatively,
use the parallel cable and the ReadVoc utility. A large output
file should result.

4) Now use Dragon Convert to extract the cassette data. Type:

DC DRAGROM

Please don't expect the conversion to work on the first attempt.
You are likely to need to adjust the command line switches until
you find a combination which is suited to your hardware. If you
still have no success then you may wish to try repeating step 3.
Upon successful conversion the file DRAGROM.CAS will be created.

5) Now use Dragon Convert again to convert the cassette data to a
cartridge file. Type:

DC /D DRAGROM.CAS

This should produce the file DRAGROM.DGN in the current directory.

6) If you have a Dragon 64 then you may optionally also wish to
transfer the 64K version of the Dragon ROM. This will enable you
to use the emulator in 64K BASIC mode. The procedure to transfer
this second ROM is much as before. Boot up your Dragon 64 and
switch to 64K mode by typing `EXEC 48000'. Now commit the second
ROM to cassette by typing:

CSAVEM "D64ROM2", &HC000, &HFEFF, 0

Transfer this file to your PC by using the procedure described
before in steps 3 to 5. This time the result should be the file
D64ROM2.DGN.

== File Formats ==

=== CAS File Format ===

The CAS file format was originally created for the PC-Dragon emulator and is one way of representing programs or data stored on Dragon cassette tapes. The CAS file format comes in two flavours, the most usual and default format is modelled after how the Dragon actually stores data on cassettes, optionally with truncated leader bytes to minimise the file size. The alternate format is simply the RAW bit stream and was only used for games that did not conform to the standard tape format (an early form of copy protection).

The standard ''Dragon'' tape format is:

1. A leader block of $55 multiplied by the 16 bit number in location $90:91 (default 128). 2. A namefile block. 3. A blank section of tape for processing of the namefile block. 4. Another leader block of $90:91 bytes of $55 5. One or more data blocks. 6. An end-of-file block.

A header block, data block or EOF file block consists of:

1. A leader byte - $55
2. A sync byte - $3C
3. A block type byte:
00=namefile block
01=data block
FF=end-of-file block
4. A block length byte (0-255)

5. 0-255 bytes of data. For a namefile block this consists of:
5.1 An 8 byte program name
5.2 A file ID byte where:
00=BASIC program
01=Data file
02=Binary file
5.3 An ASCII flag where:
00=Binary file
FF=ASCII file
5.4 A gap flag to indicate whether the
data stream is continuous (00) as
in binary or BASIC files, or in blocks
where the tape keeps stopping (FF) as
in data files.
5.5 Two bytes for the default EXEC address
of a binary file.
5.6 Two bytes for the default load address
of a binary file.

For a data block, this consists of the actual data to load/save and there is no data associated with an EOF block.

6. A checksum byte which is: sum of all the data bytes + block type + block length.

7. A trailer byte - $55

The first byte of a CAS file must be $55 for identification purposes. The first block of a standard format CAS file should be a namefile block, and the last block is usually an EOF block. Some games used copy protection where the number of blocks to be loaded did not match the number specified in the file header and a fake EOF block was included so that a simple copy of the file would result in a truncated file (other similar mechanisms skipped blocks or used non-standard block types).

Note that standard format CAS files may omit leaders. If leaders are required, use the FIXCAS utility to add leaders to more closely resemble the true Dragon cassette tape format. Since the standard format CAS file is a fairly simple representation of the data stream read from a tape after demodulation and decoding of the audio signals, certain properties of cassette tapes cannot be reproduced, e.g. gaps of silence (at least one game loader uses this as a copy protection mechanism that needs the RAW format of CAS to work - although this doesn't store silence it does store noise in those gaps).

The above description makes it pretty easy to create CAS files. Reading CAS files can be a bit more difficult though. Data is actually represented as a stream of bits on cassette tapes, and the Dragon uses different audio signals to represent different bit values. When decoding such an audio signal into a bit stream and creating a CAS file, the structure described above might not align to byte boundaries in the CAS file (this can occur when using DC, although DCWIN does synchronise bitstream conversions to byte boundaries). Especially the leader may not be decoded to an integral number of bytes. To make matters even worse, both leaders and sync bytes may contain noise and still be readable. A robust CAS file reader must take this into account.

For an example of a RAW format CAS file exhibiting both byte misalignment and leader noise, see [http://archive.worldofdragon.org/archive/index.php?dir=Tapes/cas/&file=Beyond%20Software%20-%20Kriegspiel.zip Beyond Software's Kriegspiel] (last modified 2009-01-04) in the download area.

== Cue extension ==
This is an extension to the format, created by robcfg and polished and implemented on Xroar by sixxie.

The idea is to add missing information about wave frequencies and silence between blocks to preserve the original structure of the tape and support custom loaders and protection schemes that rely on different frequencies or periods of silence in strategic places.

It also allows exporting the cas file as wav with proper frequencies and silences.

The extension adds a chunk of data at the end of a standard cas file so that it's completely backwards compatible.

The format of the extra data is as follows:

1. Cue data start marker (4 bytes). Value is '[CUE' in ascii and 0x5B435545 in hex.

2. Cue data blocks.
Cue data is stored in blocks with a standard format:

Type (1 byte)
Size (variable-length uint31, see below for explanation)
Data

Currently there are 3 types of blocks, with the possibility of adding more.

0xF0 Timing (4 bytes). Contains two uint16 values. The frequencies in Hz of the 0 bit and the 1 bit.
0x00 Silence (2 bytes). Contains silence duration in ms as an uint16.
0x0D Data (8 bytes). Start and end offsets of a block of data on the cas file as two uint32 values.

3. Cue data start offset. An uint32, which is the offset on the cas file of the cue data start marker.

4. Cue data end marker ('CUE]' in ascii and 0x4355455D in hex).

This is done to make easy to detect the extended cas files by checking the last 4 bytes of the file for the 'CUE]' marker and if found, read the offset of the cue data start.

The block size is stored as variable-length uint31, which is defined as follows:

* 7-bit 0nnnnnnn
* 14-bit 10nnnnnn nnnnnnnn
* 21-bit 110nnnnn nnnnnnnn nnnnnnnn
* 28-bit 1110nnnn nnnnnnnn nnnnnnnn nnnnnnnn
* 31-bit 11110XXX Xnnnnnnn nnnnnnnn nnnnnnnn nnnnnnnn

Leading 1 bits in initial byte determine number of additional bytes required.

Example files and original discussion of the format can be found on [http://archive.worldofdragon.org/phpBB3/viewtopic.php?f=8&t=5621 this thread].

=== JVC/DSK File Format ===

A disk format created by Jeff Vavasour for his Tandy emulator series, this is the simplest disk image format. It consists of an optional header followed by the DATA portion of each disk sector in order of track, then side, then sector number.

Taken from [http://tlindner.macmess.org/?page_id=86 Tim Lindner's JVC format documentation], the header is as follows:

{| border="1"
!Byte Offset !!Description !!Default
|-
|0 ||Sectors per track ||18
|-
|1 ||Side count ||1
|-
|2 ||Sector size code ||1
|-
|3 ||First sector ID ||1
|-
|4 ||Sector attribute flag ||0
|}

Sector size code indicates sector is (128 << ''n'') bytes long. The default of 1 means a sector size of 256 bytes.

The sector attribute flag indicates that each sector is preceeded by an attribute byte. This contains which bits would be set in the WD279x status field after a read sector command, and can indicate record type, record not found and CRC error.

The presence of the sector attribute flag confuses things slightly, as if it is set, suddenly the header size is the file size modulo 257 instead of modulo 256.

=== VDK File Format ===

The VDK file format was introduced for the PC-Dragon emulator (v2.05) as an evolution of original work by Stewart Orchard. Similar to the JVC/DSK format, this format contains a header followed by a raw dump of sector data. Data is in track, then side, then sector number order.

Complete header information from the source code:

{| border="1"
!Byte Offset !!Description
|-
|0, 1 ||'d', 'k'
|-
|2, 3 ||Header size (little-endian)
|-
|4 ||Version of VDK format
|-
|5 ||Backwards compatibility version
|-
|6 ||Identity of file source
|-
|7 ||Version of file source
|-
|8 ||Number of tracks
|-
|9 ||Number of sides
|-
|10 ||Flags
|-
|11 ||Compression flags and name length
|}

=== DMK File Format ===

A file format created by David Keil, carrying a lot more information about the underlying structure of the disk. Almost every piece of information that can be reported to the WD279x is recorded.

[http://www.trs-80.com/wordpress/emulation-dmk-format/ DMK Format Documentation]

[[Category:Documentation]] [[Category:Software]] [[Category:Development]]

Category:XRoar

2021-09-29T21:22:54Z

Polluks: Created page with "Supported by XRoar emulator."

Supported by XRoar emulator.

Joysticks

2021-09-29T21:21:56Z

Polluks: Category

Pictures of Dragon joysticks and boxes

== Boxes ==
[[File:TwoJoystickControllers-front.jpg|300px]] 
[[File:DragonJoystickBox1.JPG|300px]]
[[File:DragonJoystickBox2.JPG|300px]]
[[File:DragonJoystickBox3.JPG|300px]]

== Joysticks ==
[[File:TwoJoystickControllers-hardware.jpg|300px]] 
[[File:DragonJoystick1.JPG|300px]]
[[File:DragonJoystick2.JPG|300px]]
[[File:DragonJoystick3.JPG|300px]]

[[Category:XRoar]] [[Category:Hardware]]

XROAR

2021-09-29T20:56:34Z

Polluks: Redirected page to XRoar

#REDIRECT [[XRoar]]

XRoar

2021-09-29T20:52:45Z

Polluks: Created page with "XRoar is a cross-platform Dragon emulator. http://www.6809.org.uk/xroar/ Category:XRoar Category:Software"

XRoar is a cross-platform Dragon emulator.

http://www.6809.org.uk/xroar/

[[Category:XRoar]] [[Category:Software]]

Froglet

2021-09-29T20:31:53Z

Polluks: /* Screenshots */

{| align="right" valign="top"
|{{Infobox Game
|Image = [[File:Froglet_Screenshot01.png|300px|Titleimage from the game]]
|Gamenumber =
|Company =
|Developer = [[B Parkin]],[[V Parkin]]
|Publisher = [[CRL]]
|Musician =
|Release = [[:Category:Game_1983|1983]]
|Platform = [[Dragon 32]] or [[Dragon 64]]
|Genre = Arcade
|Gamemode = 1P
|Operation = {{Keyboard}}
|Media = {{Cassette}}
|Language = {{EN}}
|Info =
}}
|}

A Frogger clone by [[CRL]].

== Screenshots ==

<gallery widths=300 heights=225>
Image:Froglet_Screenshot02.png|Froglet on [[XRoar]]
Image:Froglet_Screenshot03.jpg|Froglet on real Dragon
</gallery>

== Packaging ==

[[File:Froglet_Inlay_Front.jpg|300px|Inlay Front]]
[[File:Froglet_Inlay_Back.jpg|300px|Inlay Back]] 
[[File:Froglet_Tape.jpg|300px|Cassette]]

== Download ==
* [http://archive.worldofdragon.org/archive/index.php?dir=Tapes/Dragon/cas/&file=Froglet%20%281983%29%28CRL%29%5B%21%5D.zip Froglet] (Zipped .CAS file)

[[Category:Games]] [[Category:Game_Online]] [[Category:Game_1983]] [[Category:Arcade]]

Repository

2021-09-29T20:30:18Z

Polluks: /* ToolShed */ MorphOS port

There are many Software projects around 6809, Dragon and CoCo ...

Here a link collection of theses:

=== ToolShed ===

ToolShed is a package of utilities to perform cross-development from Windows, Linux or Mac OS X computers to the Tandy Color Computer and Dragon microcomputers. Tools are included to read/write both OS-9 RBF disk images and CoCo Disk BASIC disk images, generate cassette WAV files and more.

* Webpage: http://toolshed.sourceforge.net
* Project page: http://sourceforge.net/projects/toolshed/
* Sourcecode repo: http://sourceforge.net/p/toolshed/code/
* MorphOS port: http://aminet.net/package/dev/cross/ToolShed

=== LWTOOLS ===

LWTOOLS is a set of cross-development tools for the Motorola 6809 and Hitachi 6309 microprocessors. It supports assembling to raw binaries, CoCo LOADM binaries, and a proprietary object file format for later linking. It also supports macros and file inclusion among other things.

* Project page / Sourcecode: http://lwtools.projects.l-w.ca/

=== M6809 computer tools ===

Stuff for the M6809-based Dragon and similar computers.

* https://gitorious.org/m6809-computer-tools

==== conv-tools ====
Various conversion tools for e.g. cassette and disk binary formats.
* https://gitorious.org/m6809-computer-tools/conv-tools

==== dload-dragon ====
Patched DLOAD command for Dragon 32. Uses HDB-DOS DriveWire routines to talk serial on the Dragon printer port.
* https://gitorious.org/m6809-computer-tools/dload-dragon

==== dload-server ====
A server for the DLOAD protocol, to be run on the host computer. Originally written by Burt Mitchell and ported to UNIX by Bryan Clingman.
* https://gitorious.org/m6809-computer-tools/dload-server

=== m6809 ===
Motorola 6809 dev tools: Linux packages '''xroar''', '''lwtools''', '''toolshed'''
* https://launchpad.net/~tormodvolden/+archive/ubuntu/m6809

=== '6809' GitHub organization ===
Stuff around 6809 CPU and homecomputers like Dragon 32/64, CoCo...
* https://github.com/6809/

==== DwLoadServer ====
DWLOAD server implemented in Python
* https://github.com/6809/DwLoadServer

==== dragonlib ====
Python library around 6809 computers like Dragon 32/64, CoCo...
* https://github.com/6809/dragonlib

==== sbc09 ====
sbc09 stands for Lennart Benschop 6809 Single Board Computer.
It contains a assembler and simulator for the Motorola M6809 processor.
* https://github.com/6809/sbc09

==== rom-info ====
Collected Informations/Comments for 6809 ROM Images like Dragon 32 / 64 etc...
* https://github.com/6809/rom-info

=== NitrOS-9 ===
[[NitrOS-9]] is an open-source OS-9 variant for Dragon and Tandy CoCo
* Webpage: http://www.nitros9.org/
* Project page: http://sourceforge.net/projects/nitros9/
* Sourcecode repo: http://sourceforge.net/p/nitros9/code/

=== FUZIX ===
A new UNIX-like operating system for 8-bit computers, including Dragon and Tandy CoCo
* https://github.com/EtchedPixels/FUZIX

Missing links? Just edit this page and insert it ;)

[[Category:Software]] [[Category:6809]]

Importing images into the Dragon

2021-09-29T20:24:49Z

Polluks: /* Step 4 : Displaying Image */

This tutorial shows how to convert an image on your PC to a .CAS file that you can load in your emulator, or convert it to a .WAV file so you can load it in your real Dragon machine.

== Step 1 : Preparing your image ==

First, choose the image you'd like to convert. I've chosen this one:

[[file:Spacecouv1_dry.JPG|250px]]

Which is a wonderful art by ELLioT (http://www.elliotek.net).

First, we rotate the image 90 degrees to the left to fit the screen better.

Then, we crop the image from 800x554 to 738x554 to keep the 4:3 aspect ratio of the TV or monitor screen.

If you'd like to have your image in PMODE4 (256x192 2 colors), you have to scale the image to 256x192, convert it to grayscale image and then to black and white bitmap (choose the dithering method you like most).
You should get an image like this:

[[file:PMODE4_RAW.gif]]

Please remember to convert it back to grayscale image (with an 1:1 ratio) before saving, as Photoshop doesn't allow to save 1 bit raw images and the Raw2PMODE4 tool is designed to deal with each pixel as a byte.
 

On the other hand, if you'd like your image in PMODE3 (128x192 4 colors), you have to scale the image to 128x192 and convert it to indexed color with one of the two palettes for this mode. You'll find the palette information in the downloads section below.
With this procedure, you should get an image like this:

[[file:PMODE3_RAW.gif]]

Now, you only have to save your image as .RAW file with no header. If everything's gone ok, your PMODE4 image should be 49152 bytes in size, or 24576 bytes if the image was processed as PMODE3.

== Step 2 : Packing the data in Dragon format ==

The Dragon computer packs 8 pixels per byte in PMODE4 and 4 pixels per byte in PMODE3. So, the .RAW files must be packed according to the PMODE in which you'd like to display them.

This is done by using the tools Raw2PMODE3 or Raw2PMODE4, which can be downloaded below.

Their usage is quite easy. To convert a PMODE4 raw image, type "'''Raw2PMODE4 image.raw'''", and to convert a PMODE3 raw image, type "'''Raw2PMODE3 image.raw'''". This will create a packed file in the correct format with extension .PM4 or .PM3 (depending on the tool used).

== Step 3 : Converting the image to .CAS or .WAV file ==

This step is super easy too.

You only need to use the DrBinCas tool (see the downloads section below) to generate the final file you need to see your image.

Just type "'''DrBinCas image.PM3 name 1536 1536'''" or "'''DrBinCas image.PM4 name 1536 1536'''".

For example, if we want the image to have the name "SPACE" in the .CAS file, you should type "'''DrBinCas image.PM4 SPACE 1536 1536'''".

To convert the .CAS file to a .WAV file, use the DC.EXE utility. Download link below.

== Step 4 : Displaying Image ==

Now that you have your .CAS or .WAV file, you can load it in your favorite emulator or your Dragon with this simple program:

For PMODE4 images:

<pre>
10 PMODE 4,1:SCREEN 1,1
20 PCLS
30 CLOADM
40 GOTO 40
</pre>

For PMODE3 images:

<pre>
10 PMODE 3,1:SCREEN 1,0
20 PCLS
30 CLOADM
40 GOTO 40
</pre>

The converted images should look like this on the [[XRoar]] emulator: 
[[file:PMODE4_FINAL.GIF|256px]][[file:PMODE3_FINAL.GIF|256px]]

And that's it. I hope you'll find this tutorial helpful. You can find the palettes and utilities right below.

== Downloads ==
* Utilities, palettes and source code: http://www.mediafire.com/?a32y1uvcd3ep228
* PMODE3 Palettes (RGB Values):
0 - Blue (0,0,255 or 0x0000FF)
1 - Green (0,255,0 or 0x00FF00)
2 - Yellow (255,255,0 or 0xFFFF00)
3 - Red (255,0,0 or 0xFF0000)

or

0 - Magenta (255,0,255 or 0xFF00FF)
1 - Cyan (0,255,255 or 0x00FFFF)
2 - Orange (255,166,0 or 0xFFA600)
3 - White (255,255,255 or 0xFFFFFF)

[[Category:Documentation]] [[Category:Software]] [[Category:Development]]

Emulation

2021-09-29T20:20:17Z

Polluks: MorphOS

So you want to emulate a Dragon.....

The most accurate modern Dragon 32 and Dragon 64 emulator is XRoar and this is available for many platforms direct from its homepage and has been ported to several other platforms. The next best solution is MESS which can also emulate the Project Alpha (Dragon Professional) and Project Beta machines, followed by the older MS-DOS based PC-Dragon II and T3 emulators.

One emulator that I would love to see ported is Mocha - It is a Java based emulator of the Tandy CoCo 2 and allows you to play games within your web browser - Would love to have a Dragon version to host here with full access to all the software.

Several emulators can be found in the [http://archive.worldofdragon.org/archive/index.php?dir=Emulators/ download section] of the archives.

== Windows ==

[http://www.6809.org.uk/dragon/xroar.shtml XRoar] ''Dragon 32, Dragon 64 and Tandy CoCo''

[http://www.mamedev.org/release.html MAME] ''Dragon 32, Dragon 64, Project Alpha, Project Beta plus too many others to list''

[http://archive.worldofdragon.org/phpBB3/viewtopic.php?f=7&t=566 T3] ''Dragon 32, Dragon 64 and Tandy CoCo (designed for MS-DOS - includes some enhancements for Windows 95/98 - no virtual disc support and no sound under Windows NT/2000/XP onwards)''

[http://www.zophar.net/coco.html PC-Dragon II] ''Dragon 32, Dragon 64 and Tandy CoCo (designed for MS-DOS - includes some enhancements for Windows 95/98 - no sound)''

== Mac OS ==

[http://www.6809.org.uk/dragon/xroar.shtml XRoar] ''Dragon 32, Dragon 64 and Tandy CoCo''

[http://www.mamedev.org/release.html MAME] ''Dragon 32, Dragon 64, Project Alpha, Project Beta plus too many others to list'', formerly [http://rbelmont.mameworld.info/?page_id=163 SDLMESS], but merged into current MAME development

== Linux / Unix ==

[http://www.6809.org.uk/dragon/xroar.shtml XRoar] ''Dragon 32, Dragon 64 and Tandy CoCo''

[http://www.mamedev.org/release.html MAME] ''Dragon 32, Dragon 64, Project Alpha, Project Beta plus too many others to list'', formerly [http://rbelmont.mameworld.info/?page_id=163 SDLMESS], but merged into current MAME development

== Amiga ==

=== Classic ===

[http://aminet.net/package/misc/emu/dream102 DREaM] ''Dragon 32, Dragon 64 and Tandy CoCo (requires an Amiga with at least a 68020 processor - no virtual disc support)''

=== OS4 ===

[http://hirudov.com/amiga/XRoar.html XRoar] ''Dragon 32, Dragon 64 and Tandy CoCo''

=== MorphOS ===

[http://aminet.net/package/misc/emu/xroar XRoar] ''Dragon 32, Dragon 64 and Tandy CoCo''

== Nintendo DS ==

[http://www.6809.org.uk/dragon/xroar.shtml XRoar] ''Dragon 32, Dragon 64 and Tandy CoCo''

== PlayStation Portable ==

[http://zx81.zx81.free.fr/serendipity/index.php?/categories/64-Tandy-Coco XRoar] ''Dragon 32, Dragon 64 and Tandy CoCo''

== GP32 ==

[http://www.6809.org.uk/dragon/xroar.shtml XRoar] ''Dragon 32, Dragon 64 and Tandy CoCo''

== GP2X ==

[http://zx81.zx81.free.fr/serendipity/index.php?/categories/65-Tandy-Coco XRoar] ''Dragon 32, Dragon 64 and Tandy CoCo''

== Dreamcast ==

[http://www.dcemu.co.uk/vbulletin/showthread.php?t=59509 DragonDC (port of XRoar)] ''Dragon 32, Dragon 64 and Tandy CoCo''

[[Category:Documentation]]

Dragon Plus

2021-09-29T20:00:41Z

Polluks: typo

The Dragon Plus was an add-inboard for the Dragon 32 or 64. It provided an additional 64KB of RAM and an 80 column text mode driven by an MC6845 with its own 2KB buffer. The board plugged into the SAM socket on the motherboard, with the SAM being placed on the Dragon Plus board and also required one of the BASIC roms to be moved to the Dragon Plus board with a ribbon cable plugging into the vacated socket. The 80 column display required an additional monitor socket to be provided on the Dragon case as this used its own composite video output circuit.

There was also an IDE interface planned to allow connection of a hard disk drive - the 40-pin header for the IDE interface can be seen on the Dragon Plus circuit board, along with what appears to be space for a missing IC.

A special version of Edit+ was available, along with drivers for OS-9 Level 1 and a special version of Flex. Both the OS-9 and Flex implementations used the additional 64KB as a RAM disk so the main OS ran completely from RAM, thus speeding up operating and allowing disk 0 to be changed. Both OS-9 and Flex also supported the use of the 80 column display.

== PCB Pictures ==
[[File:DragonPlus_PCB_Top_Empty.jpg|300px]][[File:DragonPlus_PCB_Bottom_Empty.jpg|300px]][[File:DragonPlus_PCB_Top_Empty_Annotated.jpg|300px]][[File:DragonPlus_PCB_Empty.jpg|300px]][[File:DragonPlus_Clone_Mask_Bottom.jpg|300px]][[File:DragonPlus_Clone_Mask_Top.jpg|300px]][[File:DragonPlus_Clone_Mask_Composite.jpg|300px]]

== Other Pictures ==
<gallery>
Image:DragonPlus_Mounted.jpg|Mounted board
Image:DragonPlus Clone PCB Top Perspective.jpg|Clonic board
Image:DragonPlus_PCB_Top_Perspective02.jpg
Image:DragonPlus_Components.jpg
Image:DragonPlus_Components02.jpg
Image:DragonPlus_Diagrams01.jpg
Image:DragonPlus_Diagrams02.jpg
Image:DragonPlus_OS9Drivers.jpg
Image:DragonPlus_TechnicalInfo01.jpg
Image:DragonPlus_TechnicalInfo02.jpg
Image:DragonPlus_TechnicalInfo03.jpg
Image:DragonPlus_TechnicalInfo04.jpg
Image:DragonPlus_Charset.png|Character set
</gallery>

== Advertisement ==
<gallery>
Image:Dragonplus.jpg
</gallery>

== Downloads ==
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Compusense%20-%20Dragon%20Plus%20-%20Chargen.zip Dragon Plus Character ROM] (zipped ROM file)
* [http://archive.worldofdragon.org/archive/index.php?dir=Roms/Dragon/&file=Compusense%20-%20Dragon%20Plus%20-%20PROM.zip Dragon Plus PROM] (zipped binary file)

== Reproduction Boards ==
A near replica of these boards was launched in early 2019 by John Whitworth, with the approval of Ted Opyrchal, ex-MD of Compusense. The boards are functionally identical though they do not have the empty expansion pinout at the bottom, which was never utilised anyway. The boards can be purchased, in kit form, [https://www.dragonplus-electronics.co.uk/?product_cat=hardware here].

[[Category:Hardware]]