Interface to real hardware ... ?

[LouDou]

Hello,

I've been interested in using real 8bit chips for music for a while, since I found a pair of AY-3-8910 chips in a pile of someone else's junk. I think they had been spares or removed from an old pinball machine.

Bear with me a little whilst I outline what's been on my project table for a while... apologies if you think I'm a little crazy.

I'll be honest firstly, and admit that I'm not at all familiar with the chiptune world as such, I'm not really up to speed on formats, software etc which is commonly used for this sort of thing. I've arrived here though a little googling and I'm impressed at the maturity and popularity of Furnace here. I thought I'd better say something and get educated as to how music is normally written for these chips.

Some time ago I built an AY module for my modular synth using one of these old chips. I an driving it using an ESP32 microcontroller, wrote a bit of code and it shows up as a USB MIDI device on the PC. I had to invent some MIDI to register mapping to turn it into a basic note synth, and it works quite well - things get pretty interesting when passing it through some modular filters and weaving it into the other synth sounds. I haven't published any information about this project or open sourced any code, but read on ...

That particular module serves its purpose in a somewhat limited way, because misses some of the AY features; I didn't get around to managing the noise or envelope generators with MIDI messages. But, off the back of that, I am now considering how to build more real AY modules, and I bought a bunch of chips recently for quite cheap. I now have 10 new ones and 1 vintage looking for an application.

So, I'm looking at making an entirely AY synth; probably 4x AY chips and 12x VCFs in the box all hooked up to an ESP32 and available as a MIDI device over USB.... or perhaps available as some other interface or protocol which can be driven directly by Furnace? Since you've got the tracking all there, and support for multiple devices and all the register data ready to stream .... how might we get that data into an array of real chips? (BTW, I realise that the VCF additions might have to remain a MIDI-only feature, since I don't think the AY formats support anything to do with filtering? But, that's something I want to explore, to add a dimension to the sounds). I would be interested in open sourcing the entire design for this thing, the hardware/circuit designs and the firmware for the microcontroller.

I'd be interested to hear from anyone who thinks this is a worthwhile project.

Regards,
Doug.

[MarisaKirisame7]

I wonder the same thing how to use the command stream export file to run the AY-3-8910 chip

[LouDou]

I have now actually published information and firmware on my multi-AY synth project:

• https://fourays.lon.dev/
• https://bitbucket.org/doughammond/fourays

If anyone has details on how to stream AY commands out of furnace I could have a go at implementing that into my firmware.

[Abdullah-Ajeebi]

As @tildearrow said in another discussion:
#1857 (comment)

The command stream is a bit like MIDI. It contains notes, effects and stuff.
In order to play a command stream in real hardware, you must write a driver which interprets the command stream.
Be noted that a command stream does not contain instrument or sample data - only sequence.