A simple PRU test with an assembler
Although there are many complex and far more sophisticated tests for the PRUs, our intention is to create a very minimal test recipe that you can observe from user space.
To do this, we will use a C program that runs directly on our BBB's ARM processor. From Linux user space, it will give a big hug to the PRU, upload an assembler code binary, run it, then pass and fetch information between the ARM and the PRU.
The basic steps are:
Create a program in assembly language for the dedicated hardware (the PRU)
Note
The PRU only speaks assembly!
Create a program in C for the main CPU (BBB's ARM)
Note
This program reaches over and handshakes the assembler code on the other PRU.
Run a PRU test with the combined (compiled) magic of the first two steps.
Getting ready
The usual minimal setup is all you need: a BBB powered over mini USB with Internet connectivity. You will also need to have executed the preceding recipe on prepping and enabling the PRUs.
Note
Be sure that you are...
