GPIO16 as input not working?

  • Hi

    I am trying to use GPIO16 as input on an M5Stack Core, but it does not work.
    I tried using GPIO35 instead and that worked fine.

    But I want this signal on GPIO16. Any ideas on how to make that work?
    When searching for info on this I have not found any info that it shouldn't work. In general it says that it should work to use GPIO16 both as output and input.

    I am using GPIO17 as output and that is working fine.

  • Hello @Thomasx

    judging from your other posts I assume you mean M5Core2 (the one with touch interface). If so on M5Core2 GPIO16 and GPIO17 are used internally for PSRAM - they cannot be used for anything else.

    Note: if for whatever reason you really need GPIO16 as output you'd need to switch to an M5Stack (Basic, Go or Gray). Not M5Stack Fire as it also has PSRAM.


  • GPIO is written in PinMap of M5Unified.