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:
Once the devices show for you:
echo “test30” > /dev/rpmsg_pru30
echo “test31” > /dev/rpmsg_pru31
rpmsg_pru.zip (170 Bytes)