Listed is a brand new 24KB RAM EXPANSION BOARD for the cartridge port. It's ready to use. Simply insert it into the VIC20's cartridge port and power up your VIC20 to see the RAM increase. The board also comes with a RESET button that you can simply (and gently) press it to reset the VIC20 without powering off the VIC20.

I have a couple left that I don't use. Let me know if you need more than one. Please note that board delivered will not have chip sockets. That is, the chips are directly soldered into the board, not mounting on sockets.

The VIC20 comes with 5KB of RAM built-in; out of that 5KB, only 3.5KB is available. That's why you see the VIC20 displays 3583 bytes (3.5 x 1024) available for BASIC when you turn on the VIC20. NOW...With the additional 24KB, your VIC20 now has 27.5KB. This is why you will see 28159 bytes (27.5 x 1024) available when you boot up the VIC20 with the RAM expansion board inserted.

The 24KB expansion is made possible for the THREE 8KB blocks in the VIC20 memory map, BLK1 ($2000-$3FFF), BLK2 ($4000-$5FFF), BLK3 ($6000-$7FFF), respectively. You can now use these memory areas for assembly code, etc. And VIC20's BASIC is also seeing this. Please note that this is all the information provided in the listing. There are a lot of information available on the internet regarding VIC20's memory map and how to use it.