SoftwareSerial, how do I convert those projects to use the hardware serial on the M5?



  • Hello

    I am a newbie trying to understand how to convert the sample grove code for their 125Khz RFID from a SoftwareSerial to be able to connect to the hardware red grove connector on the side of the M5 stack?

    link text

    Sorry, another newbie question... I am a little confused as the module says grove serial port with TX & RX but the documentation on the grove port on the M5 seems to refer to SLA or SPI?

    Also in general question... I see a lot of sample Arduino tutorial code that uses SoftwareSerial, how do I convert those projects to use the hardware serial on the M5?

    Thank you for your help.



  • Hello @pipy71

    On M5Stack (Fire, Gray, Basic) the red Groove port A is only usable for I2C communication. The reason is that the same GPIOs (21, 22) are used internally for I2C communication with the IP5306 and therefore cannot be reprogrammed to be used as serial port.

    Please also check out Pin Map for red Groove Port A here.

    For serial communication you'd need a M5GO Bottom (or Bottom2) which provides you with the blue Groove port C.

    Thanks
    Felix