New MT32-pi-lite official board - could this board do arcade analog audio?

[callanabrown]

Today in the update we have an official MT32-pi-lite board which attaches to a Raspberry Pi Zero 2 and provides a very easy connection to the user port.

MAME has advanced analog audio simulation for older arcade games like Donkey Kong using circuit simulation that seems to be far outside of an FPGA's ability.

If we were to run MAME (more specifically just the audio drivers) on the Pi Zero, could we send triggers from the arcade cores and mix the audio back in?

I'm really interested to know if there's any reason this wouldn't work!

[pgimeno]

MAME has advanced analog audio simulation for older arcade games like Donkey Kong using circuit simulation that seems to be far outside of an FPGA's ability.

I don't think that's accurate. Most likely it's simply beyond the expertise of the developers of the core. I'm pretty sure that it can be emulated accurately in the FPGA using digital emulation of the analog circuitry just like MAME does; it's just that no one knows how to code it, or no one thinks it's worth their time.

If we were to run MAME (more specifically just the audio drivers) on the Pi Zero, could we send triggers from the arcade cores and mix the audio back in?

That could probably be done already with the DE10's ARM, similarly to how the Minimig hybrid emulator works, or how built-in Timidity MIDI support works in a MiSTer.

So, I don't think you need a Pi just for this; just someone with enough will and knowledge.

[dshadoff]

Indeed. Currently, some such sounds play back digital samples, and some are not accurate (but others are accurate). MAME is in the same state.

It is important to ensure that when these are found to be incorrectly generated, an authoritative source for the sound needs to be identified. I have seen reports (for different types of ‘issues’) which cite emulators as their authoritative source…only to be proven wrong when tested on original equipment.

Once that source is found, Digital samples tend to be the most efficient way of implementing a decent sound without a lot of effort, but if somebody is energetic, there are always ways to model analog circuits.

If it can be done by, say, a Pi, then it can be done on-board on MiSTer. Just a matter of getting good information to begin with, and interest to implement.