WIP: 16C firmware hack for more memory

[Garry Lancaster]

(03-05-2023 01:37 AM)brouhaha Wrote:  The 15C microcode goes to absolutely HUGE lengths to make variable-length instructions work. (And there are bugs in it on both the 15C and 41C.) While it's obviously possible to hack the 16C to do that, it would be an enormous task.

Also, going to two-byte instructions "in-place" where the one-byte instructions are stored now is also too much work. Too much of the microcode is dependent on the way the instructions are stored.

The "easy" approaches are to keep one byte where it is, and store the second byte in a parallel structure.
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Very interesting indeed - thanks for all the insights. A parallel structure for the second byte sounds like quite a clever solution.