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faulty opcodes implimentation in simz80.c #1

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dallday opened this issue Feb 15, 2021 · 0 comments

dallday commented Feb 15, 2021

After playing with the code I thought I should let you know that I don't think these opcodes are correct.

This is decrementing the BC register but it should be just decrementing the B register, and it's not setting the Z flag.
INI

The decrement of B is actually decrementing C and putting it in B
It should then be checking if B is zero.
OUTI
IND
OUTD

The cb_prefix bit check opcodes are updating after the check even when they are just checking.

Stay safe
David

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