Cannot get pinmuxing to work

[lk....@gmail.com]

Hi,

I'm a newbie trying to program the Beaglebone Black PRU for a school project and I'm having some trouble with pinmuxing on the board.

I'd like to connect some of the board's pins to the PRU, but some of them don't work. For example, running the following command :

    config-pin -a P8_45 pruin

Yields the following error :

    P8_45 pinmux file not found!

    bash: /sys/devices/platform/ocp/ocp*P8_45_pinmux/state: No such file or directory

    Cannot write pinmux file: /sys/devices/platform/ocp/ocp*P8_45_pinmux/state

I tried running this command before, but nothing changed :

    config-pin overlay cape-universala

Do you know what the problem might be ?

I am using the Debian 9.2 2017-10-10 4GB SD IoT image found there and this is the output of uname -a :

    Linux beaglebone 4.4.91-ti-r133 #1 SMP Tue Oct 10 05:18:08 UTC 2017 armv7l GNU/Linux

Thanks in advance,

Loïc

[Robert Nelson]

On Tue, Oct 24, 2017 at 12:04 PM, <lk....@gmail.com> wrote:
> Hi,
>
> I'm a newbie trying to program the Beaglebone Black PRU for a school project
> and I'm having some trouble with pinmuxing on the board.
>
> I'd like to connect some of the board's pins to the PRU, but some of them
> don't work. For example, running the following command :
>
> config-pin -a P8_45 pruin
>
> Yields the following error :
>
> P8_45 pinmux file not found!
> bash: /sys/devices/platform/ocp/ocp*P8_45_pinmux/state: No such file or
> directory
> Cannot write pinmux file:
> /sys/devices/platform/ocp/ocp*P8_45_pinmux/state

P8_45 is used by hdmi:

in /boot/uEnv.txt you need to set:

disable_uboot_overlay_video=1

and reboot


Full Docs are here:

https://elinux.org/Beagleboard:BeagleBoneBlack_Debian#U-Boot_Overlays

Regards,

--
Robert Nelson
https://rcn-ee.com/