While testing pins as GPIO outputs on the J21 header on my Jetson TX2 development kit (L4T 32.1) with a multimeter I noticed a significant number of them not working and deviating from what kernel gpio debug reports. Judging from older posts this is “normal”, for reasons ranging from physical layout to drivers blocking the pins.
Is there an definitive list of which pins can be used right away and which can be enabled to be used as GPIO?
And for the ones that have to be manually enabled first, is there a foolproof guide on how to do so?
My clumsy attempts at changing the dtb wit the help of older guides on this forum on pinmuxing didn’t result in any changes.
Thanks in advance