Z80 version

A project log for One kilobyte Tiny BASIC for the 8080 and Z80

BASIC for the 8080 and Z80, fits in 1K of memory, runs BASIC games on a 2K system. Features similar to Palo Alto Tiny BASIC.

willstevenswill.stevens 04/10/2024 at 22:524 Comments

I’ve started work on a Z80 version. It will be at least 24 bytes shorter than the 8080 version due to the Z80s two-byte relative jump instructions. There will probably be a few other places where space can be saved due two differences between the 8080 and Z80. For example, the LDIR and LDDR instructions might end up making memory move subroutines that are shorter than the memory rotation subroutine used for program editing. 

It would be good to be able to implement PEEK, POKE, IN and OUT instructions. 17 bytes will be needed just for the keywords, and maybe 25 bytes to implement all of these, so it probably will be possible to fit them in.

I’ve made a change to the 8080 version so that it should also run on a Z80. In PrintSub I found a way to avoid using the parity bit without using any more space. This change is committed to GitHub, and when time permits I will rerun all tests and make release v1.0.1 with this fix.


mayosebaai wrote 04/18/2024 at 18:38 point

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mayosebaai wrote 04/18/2024 at 18:37 point

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mayosebaai wrote 04/18/2024 at 18:35 point

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Boxerbomb wrote 04/11/2024 at 14:31 point

Nice! I am excited about the Z80 version.

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