P9_XX_pinmux was not found under

Hello! First of all I apologize for asking something that was explained a few days ago, but I could not solve the problem.

I was using an old version of the Beaglebone (rev. A6) and things worked out fine. Now I’m using another Beaglebone (rev. C0) and a simple code like this below no longer works. I’m using the latest version of Debian Jessie “bone-debian-8.7-iot-armhf-2017-03-19-4gb.img” available at beagleboard.org.

I checked in this post below that Robert Nelson suggested this latest version “bone-debian-8.8-iot-armhf-2017-07-01-4gb.img.xz 2017-07-01 11:43 394M”. Does this version solve the problem? If it does, I’ll have no problem reinstalling my system, but I’d rather it was not necessary …

Robert Nelson also suggested updating “U-Boot_Overlays” and I did that. But it didn’t solve the problem:

POST: https://groups.google.com/forum/#!searchin/beagleboard/pinmux|sort:relevance/beagleboard/AvRrv9aaFbw/9KgYJ9wVAgAJ
U-Boot_Overlays: http://elinux.org/Beagleboard:BeagleBoneBlack_Debian#U-Boot_Overlays

Please, help me to solve this problem… I do not have much knowledge and I have been trying for several days.

Please run:

sudo /opt/scripts/tools/version.sh

so we can see how your board is configured, to help you solve the P9_13 issue.