VIC-20 35k Memory expansion PCB
This is a custom PCB based on the schematic from Ruud Baltissen
The colour of the PCB will either be blue or green.
http://www.baltissen.org/images/mem-exp.png
DIP Switch Settings:
- all off – Expansion Disabled
- 3 ON – 4607 free
- 1,2,3 ON – 6655 free
- 4 ON – 11775 free
- 4,5 ON – 19967 free
- 4,5,6 ON – 28159 free
- All ON – 35k
Warning: Do not plug/unplug any expansion card while the computer is on. You risk damaging the computer and the expansion card
The PCB connects to the expansion slot and by selecting various jumpers you can enable up to 35Kb of memory for your Commodore VIC-20.
Parts you will need to supply yourself:
- IC1 – HY62256, 32kbyte static RAM
- IC2 – HY6264
- IC3 – 74LS21
- RN1 – 8 way resistor network 10K
- SW1 – 8 way DIP switch