• pinMode 'input' - Digital input: Is the pin in tri-state mode?

    Yes - it is just leaving the input floating.

    I'm not entirely sure what you're trying to do though? In SPI you have 3 pins:

    • CLK - master -> slave
    • MOSI - master > slave
    • MISO - slave -> master
    • And often chip select, which is also master-> slave

    The master never has to change the state of any of its pins, and Espruino can only be an SPI master so I don't think you have a problem.

    It's actually not a good idea to leave SPI pins from a master tristate since electrical noise could then potentially send random data to the SPI slave(s).

    If it were an SPI slave then yes, as I understand it the device would have to tri-state its MISO pin when the chip select was high (unselected), but I believe that's something that is done in hardware

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