Pokey two tone timing problem
20 POKE P+8,64
30 POKE P+1,10+32
31 POKE 53775,11
40 POKE P,20
50 GOTO 50
high pitched, low pitched on real Atari
Updated by foft over 5 years ago
Updated by foft about 2 years ago
This was fixed following investigation and a simple test case/detailed spreadsheet from Synthpopalooza.
I used these new audio test pcbs and a cycle exact fpga comparison program to check it against the real pokey.
Incidentally I found another few small intermittent cycle differences which I'll be able to track down with this too.