stm32mp1-baremetal VS mt32-pi

2x A7 cores for running an OS (Linux, Android) or you can run bare metal code on them too. (https://github.com/4ms/stm32mp1-baremetal)

stm32mp1-baremetal and forum post and summary, linker script

As others have said, it’s not real-time Linux because it’s not Linux. I also want to add that if you require hard-real time and are ok with not having Linux, you can also use the A7 core for hard-real time applications. Some example projects here: stm32mp1-baremetal

I didn’t go through the 29 bytes you’re sending to the codec, but I do see you call the array “master”. The codec should be setup as slave. It could cause problems if the codec and ARM chip are both trying to be the master (generating the clocks). You’ve double/triple checked those bytes set up the codec properly? You may want to spell them out like I’ve done here: https://github.com/4ms/stm32mp1-baremetal/blob/master/examples/audio_processor/lib/mdrivlib/drivers/codec_CS42L51_registers.h

And if you want more processing power and memory, there are some audio examples in this project using a Cortex A7 (STM32MP157) bare-metal (512MB RAM, 800MHz) https://github.com/4ms/stm32mp1-baremetal

I have just seen https://github.com/dwhinham/mt32-pi but it doesn't seem as easy to play with and well-documented as the other software I've used.

Cool system. I'd see if you can get a hold of a Roland MT-32 type synth. If your sound card has a daughterboard connector (it does, top right corner) you can get a Serdaco Wavetable board which would let you have generalMIDI output. An external MT-32 or a mt32-pi will also greatly improve your music output.

Regardless the best option is a MT32-pi solution. https://github.com/dwhinham/mt32-pi/wiki/Custom-hardware

I think MT-32 and SC-55, at least, are wildly overpriced for what they are from a music perspective, thanks to the retro gaming bubble. If you want to mess around with one, I would recommend checking out mt32-pi. In addition to the extremely limited MT-32 sound palette, it can also load soundfonts, which really opens things up a lot.

Check out Mini-Dexed and MT32-Pi. I use both and they're great. They are built on the bare-metal "circle" platform, so they don't run on top of linux (so no faffing about with JACK routing, etc.).

its a CJMCU 5102 DAC Board, which is one of the supported soundcards. You can use the internal headphone jack of the Pi as well, however it only supports 12bit PWM audio there, which is usable but has a lot of artifacts and I would not recommend therefore

You can turn a Raspberry Pi into a Yamaha DX7 using MiniDexed or a Roland MT-32 using mt32-pi (which also loads soundfonts via FluidSynth). I use both of these regularly. They're great. Both work with USB MIDI controllers with no additional hardware required and boot headlessly in a few seconds to work like a true instrument.