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~MS & ~FS are supposed to be connected together on the D64 motherboard. The schematics had a problem whereby the original was creased right where that connection was. On my lower case board, and probably as per the 200E board, ~MS on the 6847 is connected to the socket, whilst ~FS is connected to ~...

On the original lowercase PCB, pin 37 of the header (FS) is not connected to anything. You can see this here: Screenshot 2024-11-20 224806.png This is the original PCB photos superimposed, the bottom reversed, and the top is set to 50% opacity. Pin 37 on the header is the 4th from the right top. Not...

Hi Jim, Sorry - I have been busy on other things. I have conquered the file once, but every time I look at it again it confuses me. I view the file in a hex editor, 256 bytes wide, so that each character can then be read downwards over 12 rows. You then get 2 sets of 128 characters in each 12 rows....

Very nice! It's also good that you managed to reduce the board size. If the eprom could be changed by one in PLCC package and the rest of the components rearranged, maybe we could get two boards in a single 100x100 pcb thus helping reduce the price. Congratulations! Actually, you can now, as one of...

It works!

https://www.go4retro.com/2024/11/17/exp ... ce-part-2/

John put some secret data in his own font files: https://www.go4retro.com/2024/11/16/exp ... ts-part-2/

I have a Dragon 200 (which is a D64 in a fancy new case) with the 1st version of the Dragonplus daughterboard and the D200-E roms and it works like a charm! Good to know. I see John is out of stock on the kits, not sure if he's planning to make another run. I put my progress to date up on github: h...

We got you covered! :mrgreen: https://archive.worldofdragon.org/browse/downloads/Software/Dragon/Eurohard%20Ltd/Dragon%20Firmware/Dragon%20200E%20-%20Rom26%20(1985)(Eurohard%20S.A.)%5B!%5D.zip Thanks! OK, all test point to the INV line being EPROM address line A7, which selects the upper or lower 1...

I'm still not for certain, but it looks like the !INT/EXT line on the 6847 socket is used to select which of the 2kB banks in a 4kB ROM set you use. If so, that helps explain why the font sets are 4kB in size. Does anyone have a dump of the original EPROM or a link to it? That would assist in unders...

I thought I'd reach out to DragonPlus directly, but their contact form is disabled.
JIm