Hi,

not opl, but also a sound device
I could find only this one
https://github.com/mcgurk/Covox

listed also on vogons

The comprehensive list of all modern reproductions of vintage sound cards

https://www.serdashop.com/OPL3LPT

I was actually thinking about something like that: a software-defined sound device like the PicoGUS or PicoMEM, but with a parallel port interface instead of an ISA interface.

With something like a Raspberry Pi Pico, it should be really cheap and relatively easy to implement, and with proper programming, it could emulate pretty much every parallel port sound/game device imaginable:

• Covox Speech Thing (LPT DAC)
• Stereo-on-one (LPT DAC with stereo support)
• Disney Sound Source (LPT DAC with a FIFO buffer)
• The FTL Sound Adapter, including the 9-pin game port supported by Dungeon Master
• OPL2LPT
• OPL3LPT
• Digispeech (DS311 or DS311A), with both FM synthesis and 16-bit PCM sound, and Adlib and Sound Blaster emulation through a driver
• A new variant of the Digispeech that emulates OPL3 instead of OPL2

One step further than that: a more advanced variant of such a device, which would have both a parallel and a serial interface (which you would ideally plug into a both ports on a computer or laptop, through two cables). Such a device could then emulate any of the above, plus an MPU-401 MIDI interface through the serial port. This would then be compatible with the MPU-232, as well as the native RS-232 interface on some Roland MIDI modules, and would work with the SoftMPU driver. Alternatively to MPU-401 emulation, this device could perhaps also support serial mouse emulation when a USB mouse is attached to the device.

A parallel interface is even easier to interface a microcontroller with than the ISA interface, right? Just pick a microcontroller that has enough GPIO pins, wire up each I/O pin on the LPT port, use level shifters where voltage conversion is needed, hook up a high quality sound output device to the microcontroller through its I2S interface, and offer a USB port and possibly a 9-port Atari-style game port for the FTL Sound Adapter emulation, if enough GPIO pins are left for one.

And then do all the magic in software. 🙂

Full Sound Blaster and MPU-401 emulation for such a device, even in protected mode games, could be accomplished by adding support for it to SBEMU and/or VSBHDA.

Or am I missing something?

vic911 wrote on 2025-05-26, 05:00:

not opl, but also a sound device
I could find only this one
https://github.com/mcgurk/Covox

Oh, cool. I didn't know about that project yet. Thanks for sharing.

I wonder if the ESP32 microcontroller is powerful enough to also emulate an OPL2 or OPL3 FM synth. If so, perhaps Digispeech emulation support could be added to it as well. (OPL2 + 16-bit stereo DAC)

somebody already tried it, with limited success
https://github.com/skiphansen/esp_box_opl3/

but if somebody smart enough and has plenty of time it can be achieved.
I think an overclocked rp2040 is not that far from an esp32
https://kilograham.github.io/rp2040-doom/sound.html

I think that's interesting, as a proof of concept.
On other hand, I don’t see the point of emulation.
I mean, I love emulators but when I'm tinkering with old hardware,
then I do it exactly because I want to see real hardware at work in first place.

i personally dont like the put a raspi pico everywhere scheme, even if its handy for debugging things or booting quickly here it makes sense for me.
But if original ics become scarce its still a good idea.
Do you expect to source sn76489, saa1099, opl3/opl2 at cheap prices for a long time ? i guess not.

the firmware is already almost there, look at picogus, picomem with sound etc.
basicly just adress decoding needs changes and unwanted stuff stripped out also required tsr software is already here.
So at least for Chips which work with portmapped i/o, it would be not so hard to fit the pieces together.

..
When orignal chips (for sound etc) are nolonger available, then I'd look for functional clones.
If they're nolonger available, then I'd simply stop here (make a pause) and use an full vintage PC emulator on a PC/Mac.
Edit: I hope that the equivalent of 3D printing will eventually be available for making ICs, too.
Simple ICs from the 1970s, I mean. Which are made in microns, still.