Playing with acceleration maths on the PRU, based on Atmel's AVR446 application note.

Playing with acceleration maths on the PRU, based on Atmel’s AVR446 application note.

The video shows the BBB doing a nice and slow ramp up to 1900 rpm (200 kHz step frequency). I estimate the PRU could reach past 500 kHz, but even 200 kHz is way too fast to be of practical use. The point is that timing is smooth, and there is a lot of headroom for other tasks.

Stretch goal: Motion control for my delta 3d printer!

It’s all fine. But why not publish a step by step work?

@Dmitry_Filatov I have several reasons: Because it is a lot of extra work. Because I am not sure anyone is really interested.
If you ask nicely, I would be happy to send you the code.

Is it running on linux ?

The realtime part, which includes ramp generation, executes on the PRU. There is a command fifo which is fed by a python script using PyPruss. This runs on the default Ångström distribution.

@Hakan_Langemark thanks. my mail dmfilat[a]

I too find it very interesting. Could you share the code. Thanks.

@Hakan_Langemark I’m interested in motion control with the BeagleBone and would like to take a look at your code – mike.hatalski[at] – many thanks!

Thanks for your interest. I will put it up on github and let you know where to find it.

Ok, it’s on github now:

Thank you for sharing