https://devzone.nordicsemi.com/f/nordic-q-a/30414/how-to-use-p0-21-as-normal-gpioI am able to disable the reset function of P0.21 by erasing UICR register and undefining CONFIG_GPIO_AS_PINRESET . Still i can&#39;t set P0.21 as output and set it to 1.en-USTelligent Community 13Fri, 16 Feb 2018 10:11:02 GMThttps://devzone.nordicsemi.com/thread/121061?ContentTypeID=1Fri, 16 Feb 2018 10:11:02 GMT137ad170-7792-4731-bb38-c0d22fbe4515:7aae6a8c-c9f0-4a58-8ed6-ec12e91de4d3Mttrinh<p>Hi,</p> <p>What do you mean by can&#39;t set it as output? What is wrong? Any error messages?</p><div style="clear:both;"></div>