Fixed block IN decrementing B too early

kosarev / z80

Fast and flexible Z80/i8080 emulator with C++ and Python APIs

MIT License

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Closed simonowen closed 2 years ago

simonowen commented 2 years ago

INI/IND/INIR/INDR all read from the port before decrementing B.

Visual Z80 remix also confirms that B is decremented after BC is put on the address bus.

simonowen commented 2 years ago

I noticed that B was decremented too late for OUT instructions in #8, but hadn't noticed that IN was also reversed too.