I ran into the same problem. Turned out that P9_25 is reserved for audio even though it is colored as an "available digital" pin. To free up this pin for usage, modify the overlay configuration file:
nano /boot/uEnv.txt In this file, uncomment the line that disables audio overlay: disable_uboot_overlay_audio=1 After reboot, I can use P9_25 as intended. On Wednesday, July 12, 2017 at 7:57:24 AM UTC-4, Kevin M. wrote: > > Hi, > > I am currently using a BBB with Debian Jessie 8.8 and 4.4.x kernel > installed. I was trying to configure the P9_25 pin using the command > "config-pin P9_25 gpio_pu" but the BBB keeps throwing me the error > > P9_25 pinmux file not found! >> bash: /sys/devices/platform/ocp/ocp*P9_25_pinmux/state: No such file or >> directory >> >> > I have loaded the cap-universal-00A0 overlay from this github page > > https://github.com/cdsteinkuehler/beaglebone-universal-io > > and I believe that it should have created a P9_25_pinmux dir in the > /sys/devices/platform/ocp/ which is apparently missing. > > I have been working on this for a couple of days already mostly because I > don't know much about embedded system as I'm currently a newbie. Any help > would be appreciated. Thanks. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/0b6ecdaf-760d-4f28-baa5-95f42fe9e780%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
