Right now, even forgetting the PORT register, the 6502 is deviating from the 6509 in operation right after reset. https://github.com/go4retro/Fake6509/blob/master/ref/6509%20versus%206502.pdf Left side is 6509, right is 6502. R/W, A0-15, D0-7,PHI2 are all bridged. https://github.com/go4retro/Fake6509/blob/master/pcb/Fake6509_v2%20Schematic.pdf PORT is set to output $f (15) as per datasheet. The system goes along fine until the CMP $03fa at $f99e. The 6509 reads $f0, while the 6502 reads $f8. After a bit, the paths greatly diverge. I think I am out of my element, and need help to move beyond this. Jim Message was sent through the cbm-hackers mailing listReceived on 2018-02-25 21:03:45
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