Dragon Mythbusters: The Dragon 200E!

A place to discuss everything Dragon related that doesn't fall into the other categories.
Post Reply
User avatar
robcfg
Posts: 1323
Joined: Sat Apr 04, 2009 10:16 pm
Location: Stockholm, Sweden

Dragon Mythbusters: The Dragon 200E!

Post by robcfg »

Hello everyone!

Thanks to the generosity of user NWOBHM from www.zonadepruebas.com, I bring you pictures and high quality scans of the Eurohard Dragon 200E!

The truth is that it doesn't have an 80-column expansion card. It has a piggyback board with a rom containing a new character set (lowercase letters, spanish special characters and accents, and assorted symbols), at the cost of inverse video characters.

The piggyback board has a jumper to allow the character set to be shown in normal or inverse video.

The 200E has a new version of Basic, 1.4, which takes advantage of the new character set.

The rom files can be found in the downloads section in the rom/dragon folder.

It's possible that the 200E PCB scans appear black, that is because of an issue with the thumbnail renderer. Just click on the images until you reach the full size one.

Regards,
Rob
Rink
Posts: 236
Joined: Mon Sep 05, 2011 7:01 pm

Re: Dragon Mythbusters: The Dragon 200E!

Post by Rink »

Cool.

The 200 is probably the sexiest machine I own (but never use); great to see a variant of it.
sixxie
Posts: 1157
Joined: Fri Jul 18, 2008 8:36 am
Location: Hertfordshire
Contact:

Re: Dragon Mythbusters: The Dragon 200E!

Post by sixxie »

Interesting!

How much access do you have to this machine? ;)

What with the lack of MS copyright message on startup, I tried CLS9 and it seems to toggle between SG4 & SG6. I assume that on a real machine the external font remains selected in SG6 - tried to follow some lines back on the scans but after the NAND, traces get lost under one or other of the sockets...

It's nice to have the font as a ROM dump for a change, and not have to pick out pixels from a photo of a TV screen!

I'm wondering what Shift+7 does. Seems to put it into some other mode, like it's acting as a dead key for accented characters, but no further keypresses seem to do anything (until the next Shift+7 which just types an apostrophe).

Edit: my mistake! That's exactly what it's for, it just doesn't do anything in uppercase mode. Caps Lock is Shift+Enter instead of Shift+0. Oh and btw, that cursor (that changes in lowercase mode!) is weird!
Last edited by sixxie on Sun Sep 29, 2013 9:25 pm, edited 2 times in total.
KenH
Posts: 177
Joined: Fri Oct 12, 2012 9:50 am

Re: Dragon Mythbusters: The Dragon 200E!

Post by KenH »

Nice! One more Eurohard hidden gem discovered!
The piggyback board looks quite simple to clone. Too bad that the 6847 is soldered on most (all?) of the Dragon motherboards.

I guess Eurohard weren't that sensitive to copyrights :shock: .
Eurohard OS9 also omitted the Microware copyright message on startup.
prime
Posts: 249
Joined: Fri Apr 10, 2009 1:40 am

Re: Dragon Mythbusters: The Dragon 200E!

Post by prime »

Looks like a fairly standard external character rom circuit, there's details in the full version of the 6847 datasheet.

Cheers.

Phill.
User avatar
robcfg
Posts: 1323
Joined: Sat Apr 04, 2009 10:16 pm
Location: Stockholm, Sweden

Re: Dragon Mythbusters: The Dragon 200E!

Post by robcfg »

I still have the machine at home, as its owner would like to get the machine properly documented.

So, If you want any test to be done, just post it here and I'll try them.

But, in the end it's just a Dragon 64, so I don't expect any weird behavior rather that maybe some weird letters if the program thinks it's writing in inverse video...
zephyr
Posts: 1474
Joined: Mon Jul 21, 2008 1:18 am

Re: Dragon Mythbusters: The Dragon 200E!

Post by zephyr »

The 64K mode ROM dump seems to be corrupt.
User avatar
robcfg
Posts: 1323
Joined: Sat Apr 04, 2009 10:16 pm
Location: Stockholm, Sweden

Re: Dragon Mythbusters: The Dragon 200E!

Post by robcfg »

Nice point! I'll try the original machine when I arrive home.

Sadly, I have no manual of Basic 1.4, just to be sure. Could it be that the whole basic needs the two roms?

If it works right on the machine, I'll redump the rom.
sixxie
Posts: 1157
Joined: Fri Jul 18, 2008 8:36 am
Location: Hertfordshire
Contact:

Re: Dragon Mythbusters: The Dragon 200E!

Post by sixxie »

Nah, disassembling the 64K mode ROMs from both types of machine shows not too much difference between them. Haven't tried to pick apart why the d200e one is failing yet though.
jedie
Posts: 634
Joined: Wed Aug 14, 2013 12:23 pm
Location: germany
Contact:

Re: Dragon Mythbusters: The Dragon 200E!

Post by jedie »

Can you post the dissembled ROM code somewhere?
... too many ideas and too little time ... Related stuff written in Python:
Dragon 32 emulator / PyDC - Python Dragon 32 converter: https://github.com/jedie/DragonPy
DWLOAD server / Dragon-Lib and other stuff: https://github.com/6809
Post Reply