microPython on esp32 C3 mate error InvalidPin when use GP19 for relay.

  • User
    With microPython on esp32 C3 mate, I would like to use a 3A Relay unit, for that I use GP19 which are also dedicate for USA D+, with the following code:
    import machine
    relay = machine.Pin("GP19", machine.Pin.OUT)
    if temp > 42:
    elif temp < 40:

    But I have this error:
    Traceback (most recent call last):
    File "main.py", line 7, in <module>
    ValueError: invalid pin

    Do you know why?
    Is it possible to use GP19 for a relay even if this Pin is dedicate to USA D+?

    Thanks you,

  • Why don't you use the 1st argument (pin number) in integer format ?

  • the GP is not required, only numbers are required.