2 Replies Latest reply on Sep 15, 2014 11:27 AM by ArvindS_76

    Open-drain GPIO

      Hi,

       

      Is it possible to configure a GPIO as open-drain? It doesn't seem like this configuration is allowed through the SDK (2.0) at the moment. Will it be added in the future?

       

      Would the following workaround accomplish open-drain functionality?

       

           -Configure GPIO as output enable and set low when signal needs to be low.

           -Configure GPIO as output disable (so that it is high-Z) and allow external pullup to set the signal high.

       

      Thanks,

       

      Mike

        • 1. Re: Open-drain GPIO
          MichaelF_56

          If I'm not mistaken, IO like the LEDs, Serial Ports, etc. are already open drain and the pull-ups pull the signal high while the HW drives it low (i.e. never drives high, but floats the output pad leaving the pull-up to pull the line high).

           

          I will need to check with the team to confirm that all of the IO is open drain.

          • 2. Re: Open-drain GPIO
            ArvindS_76

            > Would the following workaround accomplish open-drain functionality?

            Yes, this will work, though you might want to disable both input and output for high-Z.

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