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This is one of my oldest projects. Internal memory expansion for BLK0 and 16k of color memory.
I have so many projects running at the same time, so I needed one more VIC 20 up and running for testing. I had one CR board with fault memories. I ordered some new old stock of 2114, but in the main time I got it running with this bad boy.
Apart form the Willy Wonka CR board that fits in the 1k x 4 2114 SRAM chips as well as the 1k x4 for color memory it needs access to some signals from the 74LS138 UC4 which decodes the internal SRAM for BLK0.
So UC4 is replaced with a small board. This also disables all internal SRAM including the 3k routed to the cartridge port.
They are then connected via a FFC. If you have socketed chips it is a 2 minute job to install.
The tower of boards on the blue Willy Wonka CR is the emulator (top) for the GreenPAK programmable circuit which handles all decoding and counter for which bank for the 16 pages of color SRAM. In between these is a small adapter board I have that makes it easy to sig the signals (LEDs) and also easy to attach a logic analyzer.