PRUs are 200Mhz with many single cycle instructions On Fri, Apr 17, 2015 at 9:45 AM, Frédéric <[email protected]> wrote:
> Le Friday 17 April 2015, William a écrit : > > Thanks for your answer. > > > I think what you want to do is possible, but really depends largely > > on how fast you expect it to be. The PRUs have access to many pins on > > the board, a few of which can be accessed in a single cycle, if > > memory serves me correctly. Less than 32 total between both PRU's I > > think. > > > > For those who know much more than I on this subject to answer, I > > think you will have to provide a bit more information. At least how > > fast you expect your setup to be. > > Servos are driven with a 500µs-2500µs pulse width, every 20ms; the > pulse width gives the servo position (1500µs for neutral). > > For the sync. variation, I don't know exactly what speed I use. I may > send a new position to all legs (18 servos) every 0.1s (I think I'm > limited by the python side, as I have to recompute all positions). > > If we use 1000 intermediate points (which is huge), it will need a > refresh of pulses widths every 100µs, which allows thousands PRUs > intructions! > > > With that said however, I do not think the rPI can even come close to > > how fast this could be done on the BBB . . . > > Yes, the RPi solution way was to keep the Veyron servo controller, > which does the servo sync. > > BTW, this board uses a stm32F103; don't know how fast it is compared > to PRUs... > > -- > Frédéric > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
