archive.worldofdragon.org

Alastair wrote:Could CB2 be connected to the speaker on the Watford Electronics device?

Definitely not, CB2 is a logic line not audio.

In terms of other control characters, the DragonPlus OS9 driver only seems to support underline, which it renders for both underline and inverse video control codes. I assume this is a hardware limitation of the DragonPlus board, so unfortunately no reverse video column / row labels, just underline...

I recently emulated a BBC speech device by Watford Electronics and thought the implementation looked quite similar to this Dragon device. The BBC device has the SP0256 hooked up to a 6522 VIA whereas this Dragon cartridge has it connected to a 6821 PIA. The BBC device has the SP0256 SBY/LRQ lines co...

tjewell wrote:Oh thanks @pernod70, was that all it needed?

Yep, just the header that describes the geometry.

Can you confirm whether it corrupts the VDG output as in my screenshots, or do I have an emulation issue?

tjewell wrote:Any ideas how I can convert Sixxie's DSK file to a VDK so I can write it to a floppy?

I simply added the VDK header with HxD, verified to work in MAME.

The 18spt version runs in MAME, though I wouldn't expect it to corrupt the VDG output:

Thanks to everyone involved, it's now in for next weeks release. I'm not familiar with the MSX architecture so had to make an educated guess as to where the ROM, RAM, and the 2 x cartridge slots are mapped. As the BIOS matches the Sony HB-75P I've mapped the Dragon in the same way, just without the ...

robcfg wrote:I've attached the roms, and also the result from MAME's romident command.

Perfect thanks What do we think the year of release was 1984 or 1985? And who should I credit in MAME's whatsnew?

I've been looking at the Sony HB-55/HB-75 in MAME and those use Sony Hit Bit branded firmware, and contain 3x16k ROMs whereas the Dragon MSX only has 2x16K.

So could I get the actual ROMs from the Dragon MSX to ensure I get them correct in MAME?

Your figure for the number of pixels per scanline is correct 904 of which 640 are displayed. Your R0 details are incorrect: The DragonPlus uses 112 (&h72). I've run FLEX in MAME and it's actually set to &71 so should read: The DragonPlus uses 113 (&h71). This brings the horizontal pixels to 912 and...