Functioning assembly code for Heathkit ET-3400 with a 6800 mpu, 2x 6821 pia to a 1408 dac
Using the Heathkit ET-3400 MPU board and Williams Electronics sound rom code from systems 3-7 pinball and arcade games.
Adding other ROM routines as and when they are sorted and usable. Currently adding prototype game Rat Race.
SYNTHS
Moving all sound routines into synth folder under source names
TODO:
Change file names to reflect source ROMs. Original Synths are from ROM 15.
HARDWARE NOTES:
user RAM is 197 + 256 = 453 bytes
at address ranges 0000 - 00C4 and 0100 - 01FF
stack pointer (SP) start 01FF
PIA1 address set to 8000
PIA2 address set to 4000
PIA1 port A output
PIA1 port B input
PIA2 port B input