New to STM - is there a clear best choice board for real-time audio & video programming / possibly ML?

[NNagy.1]

I've been recommended the G4 or F3 based just on the fact that I'm interested in DSP, but am still trying to narrow things down a bit further, or get a second opinion.

One particular project I'm especially interested in is a live audio sampler / looper, so I either need on-board ADCs/DACs or an I2S interface (I have a PMOD I2S2, so as long as I can hook that up). I would also like a board that is very little interrupt latency since this project would involve a lot of starting / stopping / manipulating signals on the fly. I highly doubt any of the boards have enough on-board memory that I can store substantial audio samples, so I'd probably need an off-board RAM and an easy way to connect to that.

In general, I like plenty of freedom with programming boards and very little hardware abstraction. I don't know if that makes a difference.

Sorry if all of these specs are trivial, and maybe any board will do, but I thought I would ask the community!

[berendi]

F3 and G4 based boards don't have much RAM. I'd rather pick one of the F4, F7 or H7 based discovery boards, some of them have 8 or 32 MBytes onboard SDRAM. You can connect a USB flash drive or maybe an SD card for permanent storage.

All of them should have ADC, DAC and I2S interfaces (I2S disguised as SPI), but you might want to check if the pins are easily available on the board, sometimes they are tied to onboard peripherals.

[NNagy.1]

Thank you for the advice! I'm currently looking at getting the Nucleo-144 with STM32F767ZI MCU. The Nucleo boards from what I can tell seem pretty bare-bone, so I don't think that would cause any issues with pin availability? Would that add extra difficulty for USB drive / SD connection though?

[berendi]

Nucleo boards have user USB ports, usable both as host or as device, but only 12 Mbit/s (USB full speed). SDIO pins should be available, it would be a few times faster.

You can't add external memory to a nucleo board, it would be very slow and error-prone, so you must work with the MCU internal memory. F7 and H7 series have lots of internal RAM, but H7 has a couple of ADC issues, so stick with the F7 then.

Yes, there are lots of available pins, but you should still check which of them are connected to the onboard peripherals, ethernet occupies a handful of pins.

[Piranha]

You have not stated what audio fidelity requirements do you have. For a generic use and testing the onboard WM8994 on many discovery boards is more than enough. Also, for example, on STM32F769I-DISCO SAI1_B and I2S2 can be routed out on Arduino UNO header simultaneously.