Thanks so much guys. The suggestion of using two BBB is great for getting the test program off the same clock domain. The issue there for me is speed. The easy way to get two BBBs working together would be to have them talk via ethernet. This would be quite slow compared to my current setup which swaps all info through PRU shared memory... perhaps an order of magnitude slower, perhaps 2? I really need the speed in order to keep this test in the realm of hours rather than days or weeks.
It is possible that I could speed things up using SPI or some such? If I find myself needing that last drop of accuracy I'll go for it. For the time being I think you all have my weird behavior... ehm, my program's weird behavior... pretty well explained, and so I will just live with the +-1 instruction wiggle in my frequency calculations. Thanks so much for the help. I learned a lot. Best, Bill On Wed, Dec 23, 2015 at 4:39 PM, Graham Haddock <[email protected]> wrote: > Bill: > > I don't think the PRU clocks are externally available. > > I don't know what your interface looks like, but if there was a clock line > involved in the data transfer, or marking when data is valid, I would look > at inverting or adding some delay in that line going to the receiving PRU. > If your interface does not look like that, then I don't have a suggestion, > other than using a second BBB for monitoring. > > --- Graham > > == > > On Wed, Dec 23, 2015 at 5:21 PM, WZ9V <[email protected]> wrote: > >> Could you use a second BBB as the capture device instead? That would >> isolate the PRUs from each other and possibly allow for the HW capture that >> was mentioned. >> >> -- >> For more options, visit http://beagleboard.org/discuss >> --- >> You received this message because you are subscribed to a topic in the >> Google Groups "BeagleBoard" group. >> To unsubscribe from this topic, visit >> https://groups.google.com/d/topic/beagleboard/zhCplP-SEok/unsubscribe. >> To unsubscribe from this group and all its topics, 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 a topic in the > Google Groups "BeagleBoard" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/beagleboard/zhCplP-SEok/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- Bill Gray Velkess 415 407 7356 -- 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.
