TI Programmable Real-time Unit software support package issues

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1

Hi all,

I am new learner of Beaglebone Black and I was trying to follow the examples of Programmable Real-time Unit software support package from TI.
I think there was a tutorial website previously but now it’s obsolete. I wonder if anybody knows where those materials is available?
The reason I asked is I am not able to successfully run any examples except PRU_gpioToggle. In particular I am interested in RPMsg transfer between ARM and PRU. For example, PRU_ADC_onChip, after I built the firmware and userspace code, and run ./pru_adc_userspace -c 5. It just shows error messages.

Reading voltage at ADC Channel: 5
/dev/rpmsg_pru30 could not be opened.
Trying to initialize PRU using sysfs interface.
ERROR: Could not open /dev/rpmsg_pru30

I think it should be just some minor issues like driver missing and such. But I don’t know where to start debugging. It would be nice that if anybody knows where the tutorial is. I feel like I’m just trying in the dark. Thanks.

Regards,
Cheng

2

Have you check M Yoder PRU cookbook?

Pierrick Rauby

3

Have you looked at libruio? it fix everything.
free support as well in group by TJ.

4

Thanks for the suggestion. This looks like a very well documented reference. I will take a look at it. Does it cover PRU based ADC? I cannot tell from the outline.

Cheng

在2021年4月23日星期五 UTC-4 下午5:31:18pierric...@gadz.org 写道：

5

It’s either remoteproc or uio right? To be honest, I don’t know much about the difference. But I am following the book by Derek Molly and in his book, he promotes remoteproc.

Regards,

在2021年4月23日星期五 UTC-4 下午5:38:16 写道：

6

I recommend for some directions and concepts the pru cookbook

https://markayoder.github.io/PRUCookbook/

7

Thanks Vinicius. This is a great recommendation!

Cheng

在2021年4月23日星期五 UTC-4 下午5:49:03vinicius...@gmail.com 写道：

8

As far as I remember the cookbook does not cover the ADC but I believe there are some simple ADC-read example directly in the image under /var/lib/cloud9/Techlab/.challenges, or here: https://github.com/beagleboard/cloud9-examples/blob/master/PocketBeagle/TechLab/.challenges/analogIn.pru0.c

They are labeled for PocketBeagle but it’s the same ti-am335x chip so they should work easily on the BBB.

Also this recent thread should be useful! https://groups.google.com/g/beagleboard/c/-WlvGEaqrKU
Hope it helps!
Pierrick

9

Hi Pierrick,

Thanks for the recommendation. They look very useful references. I will read them over. Appreciate your help!

Cheng

在2021年4月23日星期五 UTC-4 下午6:34:47pierric...@gadz.org 写道：