Thank you for your quick replies. I will work through the examples this evening.
Ok. I think I might be getting a little confused of something called mux mode5 which looks like it is specific to an example I have been following on GPIO from Derek Molloy. Can I create my own overlays to configure the mux which uses both GPIO and PRU IO? ( and the ADC if required) On Monday, January 12, 2015 at 4:57:19 PM UTC, Charles Steinkuehler wrote: > > On 1/12/2015 5:11 AM, AndyS wrote: > > Hello, > > > > I have an application which requires use of the PRU for some fast IO. I > > need to use more IO than the PRU can handle, but some of the other IO > only > > needs to operate in slow time. > > > > Can I configure the BBB to use both PRU IO and Linux controlled GPIO. > > Yes. The PRU writes to GPIO pins are not particularly slow unless you > saturate the interconnect, but the writes are posted and happen a while > after the PRU executes them (apx. 100 nS later). Unless you need > critical timings between the direct PRU outputs and the GPIO pins, this > shouldn't be a problem. > > Reads from GPIO pins are another matter. Since it is not possible to > post the reads, and the PRU (by design) doesn't execute instructions out > of order or perform speculative execution, the PRU core stalls after > issuing a read GPIO request until the data is returned from the > interconnect fabric (apx. 165 nS). > > I have timing details in the comments of my PRU code for Machinekit: > > > https://github.com/machinekit/machinekit/blob/master/src/hal/drivers/hal_pru_generic/pru_generic.p#L135-L163 > > > -- > Charles Steinkuehler > [email protected] <javascript:> > -- 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.
