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The main parts of a next generation Dragon are effectively in existence right now... A 6309 machine, with CoCoSDC and V9958 based Graphics. Keeping the SAM/VDG keeps backwards compatibility. Add something that gives CoCo3 style paged memory capability - like Tormod's MOOH, or the still vaporware CoC...

Yeah, Wordpak 2+ and multipak emulation for the Dragon in Mame will be nice wins. Thanks Pernod!

This is interesting - I have a Dragon 32 which I've just acquired that displays EXACTLY the same symptom.

It boots normally, then after a very short time, the screen instantly changes colour set and clears.

Haven't had time to investigate further, certainly a strange one.

Hello Ian and welcome! If you are on Facebook, you may find some interesting bits and pieces in the Dragon 32/64 Owners/Users Facebook group. It has a fair amount of daily activity. We now have an annual Dragon meetup too, which has been at the Centre for Computing History in Cambridge in previous y...

Hi RedBlueFlame, Reading the directory entries can be done from BASIC by getting raw disk sectors in the directory area using the DragonDOS sector read commands. SREAD is the command, and it takes a drive number, track number and sector number, and two string variables as parameter: SREAD 1,20,3,S1$...

Some excellent hacking there!

Nice one Jim!

Adjustment procedure is as follows I believe. There are two variable resistors and a variable cap to tweak. Pull the WD2797 pin 22 to GND to force it in to test mode. You now need to adjust three timing / frequency values. Firstly the main data separator clock This is done by looking at the VCO cloc...

Hi D64UK, You'll not have any luck swapping the ROMs over... they are different pin counts and pinouts - Dragon 32 uses 2x8k 24 pin mask ROMs, Dragon 64 uses a pair of 16k 28pin EEPROMs. And the initialisation code which brings the machines up differs between the two ROMs as well. Can you post a vid...

Yeah, that does look pretty much OK, perhaps it's not directly related to a doublesided format as I'd assumed, Something must be amiss though to explain the Xroar vs Mame discrepancy in behaviour.