Board booted to dip switch test page, some dips were indicated as being on when they were all off. Switch checked out ok so traced the dip outputs to one of the 2 ay-3-8910 sound chips; seems these also handle the input registers, and have no input buffers to protect them.
Swapped the ay chip and the game played but with no sound, also wouldn't select a power up and sprites sometimes blinked on and off.
Replacing two broken caps got the sound back
Button 2 traced to the other ay-3-8910 so swapped that and the board played ok. Cleared up the sprite problem too.
Board is a 2-layer and a bit warped, it came without any board fastenings - putting spacers and screws in stopped it working so it seems there's a bad contact somewhere, I tried matching the spacers to the warp of the pcb to put less stress on it but that didnt help so for the time being its back to being unsecured, with a sheet of cardboard between the pcbs
Incidentally bootleg is a 22 pin board with same pinout as tiger heli, but there are variants that have a alternate pinout;
http://www.aussiearcade.com.au/showthread.php/37251-Slap-Fight-pinout?s
Swapped the ay chip and the game played but with no sound, also wouldn't select a power up and sprites sometimes blinked on and off.
Replacing two broken caps got the sound back
Button 2 traced to the other ay-3-8910 so swapped that and the board played ok. Cleared up the sprite problem too.
Board is a 2-layer and a bit warped, it came without any board fastenings - putting spacers and screws in stopped it working so it seems there's a bad contact somewhere, I tried matching the spacers to the warp of the pcb to put less stress on it but that didnt help so for the time being its back to being unsecured, with a sheet of cardboard between the pcbs
Incidentally bootleg is a 22 pin board with same pinout as tiger heli, but there are variants that have a alternate pinout;
http://www.aussiearcade.com.au/showthread.php/37251-Slap-Fight-pinout?s