Arduino for STM32

ag123 wrote: Wed Aug 28, 2024 3:18 pm
the improvements(differences) apparently are:
- the LED is apparently at PB2 active high
- buttons for boot0 (instead of jumpers) and a user button

Also, there is different layout of pins for power near USB jack. On classic bluepill, it's GND-GND-3V, while on a weact's boards it's 5V-GND-3.3V

I find adafruit libraries reliable only for Arduino UNO and Adafruit boards. Anything else is "lucky". They wont support pin numbers greater than 127 because Arduino UNO don't have those numbers and they just don't care.

As for pin names (example PC_13) i look it as 3rd port (A,B, C , 0 indexed ...

Probably related to topic:
viewtopic.php?t=1240

For my board (bluepill and ST7735) i fixed by changing to

I think it is their official store. I've been ordering from them for the last few years.
Their bluepill is genuine STM32F103CB, the only difference is the LED on PB2 (and with USB-C)
STM32G431CB has DAC, with OK results.
I didn't have time to test STM32F411CE (25Mhz) with 8MB flash.
I did test ...

In my experiments with STM32G431 board, output of a DAC is depending on the load. Without load (just probe), it was around 2V/µS, so basicly around 1.5µS to swing from 0V to full 3.3V . When loaded with some cheap speakers with 10K input potentiometer and probably 10µF cap, it needed 50µS to go from ...

In my experience with interrupt latency, especially with timers, it goes from 0.7µ to 3.5µS to enter and around same time for return latency (exit interrupt). It depends on complexity of interrupt code, every function that have some parameters in that code will add to latency. F4 is little faster ...

DMAR register is little complicated for me to understand, i tried with CCR3 register and it worked (same as CCR2 for PB7 example)
Replace dma_cfg.tube_dst = &(dev1->regs.gen->DMAR); with dma_cfg.tube_dst = &(dev1->regs.gen->CCR3);

I also recommend to edit:

uint16_t val1[SAMPLES];
dma_cfg.tube ...

I tried Mozzi library and it's compatible with stm32duino core. Tested on stm32F103CB, STM32F401CC and STM32F411CE. All using pin PA8 PWM as audio output (as ag123 mention, STM32F411CE don't have DAC).
But it's little complex for me, and i think it would be easier for me to implement double ...

As arduino, STM32 can use high PWM pulses to create audio. With even higher resolution because of better timers hardware. STM32 have some boards with 12bit DAC ( like cheap WeAct STM32G431CBU6 ).

For a start, you could use example from https://github.com/stm32duino/STM32Examples/blob/main/examples ...

Try sketch from viewtopic.php?t=1962

It might work for you...