I thought that all of the GPIO pins defaulted to input but I'm seeing that GPIO 7 (so is GPIO 8) is set as an output after boot up. Is it being used by something? If I take it over will I cause something to stop working?
rpi 3B+ vanilla Buster
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Sign up to join this communityI thought that all of the GPIO pins defaulted to input but I'm seeing that GPIO 7 (so is GPIO 8) is set as an output after boot up. Is it being used by something? If I take it over will I cause something to stop working?
rpi 3B+ vanilla Buster
OK, I must have done something to change the settings. I did hook up an official 7" touch screen briefly and mess around trying to connect to my NAS.
I re-flashed my OS and rebooted and now all of the gpio's on the 40 pin header are coming up as inputs.
I have the same situation with my Raspberry Pi 4. I have the Pi-SPROG DCC hat and it uses SPI communication. Maybe the Pi-SPROG software automatically activates SPI communication at boot time and manually sets the SPI Chip Select GPIOs (07 and 08) High to deselect any SPI slave.
Of course, it would be better if the software would just activate the built-in (pull-up?) chip select instead of doing it manually by setting High, but that's the best explanation I can think of.