Test and fix 8080 and z80 cpu

[vbmacher]

There exist very nice set of tests which can test all flags and undocumented peculiarities of Z80:

• https://github.com/raxoft/z80test
• https://softspectrum48.weebly.com/uploads/6/6/7/5/66753101/timing_tests-48k_v1.0.tzx
• https://softspectrum48.weebly.com/uploads/6/6/7/5/66753101/timing_tests-128k_v1.0.z80
• https://softspectrum48.weebly.com/uploads/6/6/7/5/66753101/softspectrum_48_2019-03-08_21-29-34.mp4
• https://softspectrum48.weebly.com/uploads/6/6/7/5/66753101/fusetest.tap
• https://softspectrum48.weebly.com/uploads/6/6/7/5/66753101/floatspy.tap
• https://softspectrum48.weebly.com/uploads/6/6/7/5/66753101/minfo.tap
• https://softspectrum48.weebly.com/uploads/6/6/7/5/66753101/btime.tap
• https://softspectrum48.weebly.com/uploads/6/6/7/5/66753101/stime.tap
• https://softspectrum48.weebly.com/uploads/6/6/7/5/66753101/ulatest3.tap
• https://softspectrum48.weebly.com/uploads/6/6/7/5/66753101/ptime.tap
• https://github.com/MrKWatkins/ZXSpectrumNextTests/tree/develop/Tests/ZX48_ZX128/Z80BlockInstructionFlags

https://softspectrum48.weebly.com/test-results.html

These tests are written for ZX Spectrum emulators, so interrupts and ROM jumps should be replaced with emuStudio code (e.g. printing character, etc).

[vbmacher]

https://spectrumcomputing.co.uk/forums/viewtopic.php?p=94582

[vbmacher]

https://github.com/hoglet67/Z80Decoder/wiki/Undocumented-Flags

[vbmacher]

https://gist.github.com/drhelius/8497817

[vbmacher]

https://floooh.github.io/visualz80remix/

                            ____
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                   _/_,---(      ,    )
               __ /        <    /   )  \___
- ------===;;;'====------------------===;;;===----- -  -
                  \/  ~"~"~"~"~"~\~"~)~"/
                  (_ (   \  (     >    \)
                   \_( _ <         >_>'
                      ~ `-i' ::>|--"
                          I;|.|.|
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                        (` ^'"`-' ")

[vbmacher]

https://skoolkid.github.io/rom/maps/all.html

[vbmacher]

What's left:

• test input/output instructions (OT*R), try to run other tests too.
• scf / ccf undocumented
• memptr test
• memory contention (probably do not need to implement here, it is used in zx spectrum)

What works

• patrik rak's z80 test (full)
• zexall test

[vbmacher]

What works:

• z80-tests full now passes all instructions
• Q and memptr registers implemented
• IN*R, OT*R, IN*, OUT* fixed

What's left:

• Run some more tests
• Fix unit tests, ideally incorporating some ROMs maybe

[vbmacher]

Implemented crc16-based instruction testing