archive.worldofdragon.org

For more information about OS-9, or rather a modern "OS-9 compatible" operating system, you should check out NitrOS-9 at http://www.nitros9.org/

There is also loads of OS-9 stuff (too much for a cursory glance to see if anything is relevant) at ftp://www.rtsi.com/OS9/

Alastair wrote:For more information about OS-9, or rather a modern "OS-9 compatible" operating system, you should check out NitrOS-9 at http://www.nitros9.org/

There is also loads of OS-9 stuff (too much for a cursory glance to see if anything is relevant) at ftp://www.rtsi.com/OS9/

Thanks for the links. I've just has a quick glance at the rtsi site. Yep! Theres lots of stuff on there. I'll have a better look when I get some more time.

The OS9 System Programmer's Manual is also a good source of information. It has a relatively large section on writing block device drivers, and it is available from the download section of this site.

-- Rolf

rolfmichelsen wrote:The OS9 System Programmer's Manual is also a good source of information. It has a relatively large section on writing block device drivers, and it is available from the download section of this site.

Thanks for that. Chapter 6 covers the file system. It looks to support 4GB drives! Very forward thinking.

DOSonCHIP!

http://www.sparkfun.com/commerce/produc ... ts_id=8215

Comments seem to be from a bunch of people that can't read (or perhaps the user guide doc wasn't linked originally, which would be a major pain), but maybe some wariness is required...

Anyway, simple filehandle interface with read, write and seek commands. Looks good to me!

The disassembled and partly commented source for SuperDos (and DragonDos) is available.

This can be assembled with the assembler from the Nitros9 project to produce a rom
that can be used on a real Dragon, and was used to port Superdos to use the CoCo disk
controler.

Might be worth investigating using a microcontroler to hold the FAT accessing routines.
It's also worth loging at the FTDI Vinculum which is able to talk nativley to FAT formatted USB
devices.

Cheers.

Phill.

Hello Everybody
Iam Andrew couldnt belive the dragon has still got a user base after 20+years out of production.Time to get the old dragon out again
Many thanks go out to the people who has made it possible to keep the dragon alive.
Has anybody come up with a solution to this storage problem yet.
As i am interested in this also because of not having a disk drive i would like to try os9
on my modded d32 to 64 spec then can have pc share
i saw the link to that cartridge for to coco good if it would work with the dragon
Many Thanks
Andrew

I have been looking at a floppy disk emulator which basically plugs into a standard floppy disk drive cable, and stores disk images on an SD card.

We would need some floppy disk images to try and details of the following - I can see some information from earlier posts, so that appears in brackets..:

MFM/FM type? ??
number of tracks (80)
number of sides (2)
number of sectors per track ??
sector size (256 bytes I presume)
bitrate ??

If this was a direct replacement for a disk drive, would that make it easier for people to use - presumably you would then need a disk interface of some type!

RWAP wrote:I have been looking at a floppy disk emulator which basically plugs into a standard floppy disk drive cable, and stores disk images on an SD card.

We would need some floppy disk images to try and details of the following - I can see some information from earlier posts, so that appears in brackets..:

MFM/FM type? ??
number of tracks (80)
number of sides (2)
number of sectors per track ??
sector size (256 bytes I presume)
bitrate ??

If this was a direct replacement for a disk drive, would that make it easier for people to use - presumably you would then need a disk interface of some type!

DragonDOS 40T SS DD:
MFM Double Density
number of tracks (40)
number of sides (1)
number of sectors per track (18)
sector size (256)
2:1 interleave
bitrate ??

DragonDOS 40T DS DD:
MFM Double Density
number of tracks (40)
number of sides (2)
number of sectors per track (18)
sector size (256)
2:1 interleave
bitrate ??

DragonDOS 80T SS DD:
MFM Double Density
number of tracks (80)
number of sides (1)
number of sectors per track (18)
sector size (256)
2:1 interleave
bitrate ??

DragonDOS 80T DS DD:
MFM Double Density
number of tracks (80)
number of sides (2)
number of sectors per track (18)
sector size (256)
2:1 interleave
bitrate ??

bitrates (at least as far as the WD2797 is concerned ) are 256kbits/s for DD. It is interesting to note that you can read high density disks on the Dragon, if you run the controller at 2MHz (instead of 1MHz), as the WD2797 was designed to work with 8" disks which used a 500K bitrate which is the same as HD disks....

Another thing that might be worth looking into is a circuit that plugs into the WD2797 socket and emulates it, that'll prolly be much simpler that trying to encode/decode the FM/MFM signals that go to the floppy drive.

Phill.