Hi! Thanks for the fast response!
Oddly enough, there's a soundtest button and when I press that you can hear it run through a series of test audio segments. Could it be that since the audio volume control is not configured properly, it's constantly set at 0 (so no sound in game)? From the operator test screen the volume is set to "0" and pressing the volume key has no effect. Do you think that maybe the audio was intentionally clamped down at zero?
Still trying to make sense of it. I'm not sure why the throttle would be affected. I am new to MAME, does anyone know off-hand which parts of the f15se code would be a good starting point to start troubleshooting these systems?
Where can I learn about fake serial? Also, how involved would it be to fix mcs51.c to use diserial? Is there someone that's already converted something from using fake serial to diserial whose work I can use as a guide? I have decent C programming skills, maybe this can get my C++ skills up to par.
I'll download the latest MAME source in the meantime, but any pointers for a running start would be appreciated.