SOLUTION - Missing /dev/rpmsg_pru30 and /dev/rpmsg_pru31

I am in the middle of struggling while introducing myself to the PRU. I want to contribute to the world to help some other struggling individual and this seems like the right place to post a solution.

I am using Beaglebone Black Rec C.
Running the uboot_overlay_pru=AM335X-PRU-RPROC-4-19-TI-00A0.dtbo defined in /boot/uEnv.txt

If you do not see the /dev/rpmsg_pru3* devices and you expect them, the zip file I have attached has a working solution to make them show up. I believe the solution has a lot to do with the right resource file and the PRU code. They will not simply just show because you have 2 PRU’s. This may seem obvious to the more advanced PRU people, but took me a couple of weeks to figure this (and other things) out.

Here are my results after days of trying to figure out the magic to get the devices to show up:

root@beaglebone:/home/debian/rpmsg_pru# ./run.sh
rpmsg_pru30
rpmsg_pru31

Once the devices show for you:

echo “test30” > /dev/rpmsg_pru30
echo “test31” > /dev/rpmsg_pru31

cat /dev/rpmsg_pru30

- c

cat /dev/rpmsg_pru31

- c

rpmsg_pru.zip (170 Bytes)

Very helpful post Bruce thanks. I am just a PRU observer. The resource file is discussed in some TI documents it’s a way to let Linux understand what resources the PRU will need is what I understood.

I’m guessing the SDK examples I played with had this all set up.

My guess this file will be important if you use any DDR to store you’re samples.

Great to know you are on the path to success!!!

Mark

Where’s the “like” button?

Here it is → LIKE

@Bruce_Chidester the folder is empty? I cant see anything in there, i ran the command ./run.sh and i get
No such file or directory

1 Like

Thank you for trying helping others. Very glad to find this. I’m having exactly same issue. Can you please upload the zip file again because what’s showing there inside rpmsg_pru.zip is empty now. I tried to run ./run.sh and I got “No such file or directory”, ran sudo ./run.sh, I got “command not found”.

Hi @Frank_25 , did you figure out?

I created a messaging example here: Bruce Chidester / PRU Messaging Example · GitLab

This might be what you’re looking for. It has been awile.

Hi Bruce,
Thank you so much. Now I got both /dev/rpmsg_pru30 and /dev/rpmsg_pru31 right after ran ./deploy.sh, but before ran ./run.sh. Trying to understand what made them work. Saw someone mentioned resource table with 0 or 1. Found you have 0 or 1 for PRU /1 but many sample codes only have one resource table for both PRU and there are less defines in it. The two different defines in your resource tables 0 or 1 are not even there.