Arduino for STM32

mrburnette wrote: ↑

Sun Aug 02, 2020 3:44 pm

also:
https://stm32duinoforum.com/forum/wiki_ ... USB_Serial

Yes, but that's Roger Clarck's core.

More information would be nice...
What core, port, speed, sensor...

And to your main question:
https://github.com/stm32duino/wiki/wiki ... wareserial

Those are alternate pins.
PA9 and PA10 are used with USB,
PB6 and PB7 are used with I2C1
so if you cannot use them you have 3rd pair: PA15 and PB3 but you need to change pin assignment:
https://github.com/stm32duino/wiki/wiki ... wareserial

In datasheet they say that recommended max. input resistor is 50k but with 100k you should still get good reading.
I've tested this with 3V lithium coin battery (3.157 on my mulitimeter V) and got this:

There are only 3 I2C. By default only one is available (I2C 1). To access more you'll need to declare TwoWire objects ( eg. TwoWire Wire2(SDA_pin,SCL_pin); ) STM32duino Wiki: https://github.com/stm32duino/wiki/wiki/API#i2C Unfortunately some Arduino libraries are hard coded to "Wire" name and won't ...

You must have wired something wrong.
it works without any problems for me.

Check reading using 3.3V from board.

Also, if you use too high value resistors in voltage divider you'll get inaccurate reading (lower).

Does it work with Arduino IDE ??

Their (WeAct) bootloaders do not work with Arduino and stm core.
HID bootloader upload searches for device 1209:BEBA and WeAct set their to 0483:572a

I get speed up to 5-6 Mbps on F103 blue pill and 1.7Mbps on Arduino Nano (serial speed set to 2Mbps) so 1.2 Mbps for F401 isn't even fast.

There is no baud rate for USB. You can put "Serial.begin(1);" in code and it still will work as fast as possible.

Thanks.