Check instruction timings with Robert Peip's timingtest.ws

[asiekierka]

https://github.com/MiSTer-devel/WonderSwan_MiSTer/tree/main/testroms/timingtest

NitroSwan is decently close; for context, Ares passes all, while Mednafen and StoicGoose pass none.

[FluBBaOfWard]

Yeah, I can't figure out the timing of the base loop unless "in al, dx" takes 6 cycles as the documentation says...
The code is

test_jumponly:
mov cx,1000
align 2
repeat_jumponly:
nop
nop
nop
in al, dx
dec cx
jnz repeat_jumponly
ret

nop *3 = 3
in al, dx = 6
dec cx = 1
jnz = 4
total 14

I know that adding another nop adds 1 cycle, adding another "in al, dx" adds 5 cycles, dec takes 1 cycle. I even added my own jnz test and it shows that it takes 4 cycles... Not sure how to proceed.

[FluBBaOfWard]

Here is a link to my version of the timing test.
https://github.com/FluBBaOfWard/WSTimingTest