ZX81 External ROM

[kolbeck]

Testing out my new External multi ROM and Expansion Bus extender

8 ROM banks of size 8192 bytes, selected with DIP - BUT requires the original ROM in ZX81 because of display generation, tested with the followin ZX81 ROMs:
* 550, 622, 649, SG and X2

Also tested, but not working correctly because of display, but they do respond to key press:
* Skyware Forth (and variants), ASZMIC

The Bus extender supports edge connector, so interfaces can be made a bit like "PC cards" which saves soldering and edge connectors.

[TMAOne]

That looks cool. I'd could be interested in one of those.

[kolbeck]

KiCad and Gerber files will be released on GitHub as soon as I have done the final testing.