SerialSample and Raspberry Pi 3, not allowing baudrate=300?

Question

When trying the SerialSample on a freshly installed Raspberry Pi 3 on the Gpio pins 14+15, it all seems to work ok, except when trying to set baudrate=300, then an exception is thrown indicating that the value is out of the allowed range.

I do however believe that the UART used should technically allow 300. I have also found indications that the serialdevice implementation in the framework only allow 9600 and above. However, setting any other value (150, 4800 and so on) seems to work just ok (not verified with another device, but it runs within the Pi at least).

Can anyone bring clarity to this? I need to run 300 baud, and would like to avoid using an USB-serial cable, but could of course to this if needed. If the .net framework doesn't handle it, can I get it to work running Python with pyserial within Windows perhaps?

Answer 1

Hi Marcus,

This is not a limitation of the serial sample but of the software UART on the Pi3.  From the Serial Port driver developer: 1200 baud is minimum & 921600 is maximum supported baud rate in mini Uart driver.

The Pi2 has a hardware UART so may be better for your scenario.

Sincerely,

IoTGirl

Answer 2

Thanks for the information. I'm running on a pi2 now without issues for the time being.