search

MiSTer-devel / ZX-Spectrum_MISTer

43 stars 32 forks source link

Z80 Cpu test fail #23

Closed Alessandro1970 closed 3 years ago

Alessandro1970 commented 3 years ago

@sorgelig Hi, some cpu tests fail, on PC/mac fuse emulator they seem to work fine (all .tap tests).

Here they are: z80test.zip

image0 (1)

sorgelig commented 3 years ago

CCF/SCF XY flags aren't fully implemented and probably will never be. There is no known software use such undocumented behavior, but amount of work for this useless feature is enormous. Even real CPUs fail CCF/SCF XY flags depending on manufacturer. Such test shouldn't even exist as it's not reliable even on real HW. Software emus simply were tweaked to this test - no more no less.. This was discussed many times already.

sorgelig commented 3 years ago

actually you need to use z80full.tap It's passed except 2 SCF/CCF because of undocumented XY flags. SCF and CCF themseves are fully correct in documented ways. Undocumented XY flags for other instructions are also fully correct.

Alessandro1970 commented 3 years ago

Ok