zasm: document lack of support for undocumented instructions

This commit is contained in:
Virgil Dupras 2019-10-17 15:52:59 -04:00
parent f41ccdbc81
commit f806786bd3

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@ -152,4 +152,11 @@ allowed. An included file cannot have an `.inc` directive.
in the argument in the currently active filesystem and outputs its in the argument in the currently active filesystem and outputs its
contents directly. contents directly.
## Undocumented instructions
`zasm` doesn't support undocumented instructions such as the ones that involve
using `IX` and `IY` as 8-bit registers. We used to support them, but because
this makes our code incompatible with Z80-compatible CPUs such as the Z180, we
prefer to avoid these in our code.
[libz80]: https://github.com/ggambetta/libz80 [libz80]: https://github.com/ggambetta/libz80