Dragon 200E Lower Case Daughterboard ROM question

[dublevay]

OK - I am working on something.

[dublevay]

A possible new version of the lower case board. Minimised probably as much as I can - now down to 50.08 x 55.37mm.

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[dublevay]

Candidate 2. 58.34mm x 38.74mm.

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If I go ahead with these, they will be pre-assembled - apart from any headers and the DIP socket.

[robcfg]

Looks really nice!

[dublevay]

I went further, and SMD'd nearly everything!

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[robcfg]

I've been wondering if there's a way to select the banks and the inverted colour using one of the unused I/O addresses instead of doing it with switches and jumpers.

[dublevay]

I got the new boards back from James a few days ago, and fitted the remaining components. Sadly they didn't work at first, but it was seemingly the missing /MS to /FS signal. Connecting that back on, and we are in business in this D64. The lower case board is sitting in the 6847 socket, with a SuperRGB board plugged into the lower case board.

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[dublevay]

When I redo the boards, I will likely just add another jumper to either open or close the pin 12 to 37 bridge.

[sixxie]

That's a very odd result: when I measure continuity on an original Dragon 64, those two pins are definitely connected on the motherboard. So long as your carrier is connecting both through directly I can't see why your bodge wire would be needed.

But at this point I'd just be arguing against reality!

[dublevay]

Thinking about it, it doesn't really make sense, as the SuperRGB board is working alone without the link on it! I need to investigate more. Ah, mind you, SuperRGB is probably doing it's own stuff with FS.