This is a simple Forth system for the VIC-20 computer. It is about 2.5kB in size, which leaves 1 kB of free memory in an unexpanded VIC-20. As much as posible is written in Forth itself, since the token-threaded code is very compact. Apart from 2 bytes in the token table, and as many bytes as there are letters in the name, there is no overhead for new definitions.
The main purpose is to allow quick prototyping on a plain, unexpanded VIC-20 with only a tape drive. There is also a block editor using raw disk sectors, but this is using up almost all available memory, which makes it rather useless without a memory expansion (which is not currently supported).
Use the WORDS word to see all defined words. Immediate words
in yellow, regular words in white.
After making some definitions, you can save the whole system including the expanded vocabulary to disk:
0 TURNKEY NAME
You can also set the device to 1 and save to tape instead:
1 DEVICE ! 0 TURNKEY NAME
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