VIC-20 Memory Expansion with JiffyDos

£35.00

6 in stock

SKU: VIC-RAM Category:

Description

This is a total of 32k ram, organised as a 24k ram expansion and 8k cart area.

Currently ALL versions come with JiffyDOS. A non-JD product will be added later but to simplify stock we only have the JiffyDOS version at this time. There is no need to re-use your existing ROM and the board will come with a JiffyDOS rom fitted ready to use.

Loading CRT Images

When loading a CRT image, with the VIC-20, you load it similar to any other program file. As it is a cartridge image however it needs to be loaded into the cartridge memory area. This is done by using ,1 after tha load command to load a the image into its original memory area.

Example:
LOAD “Q-BERT.CRT”,8,1

Once loaded, there will be no list info or anything to RUN. You just need to simply RESET – the VIC-20 and the cartridge should load instantly just as if you had plugged it in the expansion port. Some cartridges required a SYS command to start, and that should be documented in the original cart instructions.
If the cartridge image you are loading has special copy protection, where it checks that the cartridge is not writeable you need to enable the WR_EN switch before using RESET to run the image.

If write protection is enabled at any other time it will look like the expansion is disabled, only showing 3K of ram. This is because the VIC sees that the memory is not able to be written to and not detected as RAM.