Re: [beagleboard] Re: PRU and CPU driven by different oscillators?

agleboard@googlegroups.com> wrote: > > > On Sun, 4/30/17, <dinu...@gmail.com> wrote: > > Subject: Re: [beagleboard] Re: PRU and CPU driven by different > oscillators? > To: "BeagleBoard" <beagleboard@googlegrou

Re: [beagleboard] Re: PRU and CPU driven by different oscillators?

You may find this tool from TI useful: http://processors.wiki.ti.com/index.php/AM335x_Clock_Tree_Tool On Saturday, April 29, 2017 at 10:14:31 PM UTC+3, Justin Pearson wrote: > > Thanks Graham. What do you mean by "check and verify the clock tree > behavior"? I searched the TRM for "clock tree"

Re: [beagleboard] Re: PRU and CPU driven by different oscillators?

Thanks Graham. What do you mean by "check and verify the clock tree behavior"? I searched the TRM for "clock tree" but I'm still not sure how to figure out which timers make their way through various PLLs to the PRU and main CPU. On Wed, Apr 26, 2017 at 10:00 AM, Graham

[beagleboard] Re: PRU and CPU driven by different oscillators?

Graham is right. The oscillator used for the processor is the 24MHz crystal oscillator (Y2 in schematic), whereas, the one used by the ethernet controller or the IEP timer is 25MHz crystal oscillator (Y3 in schematic). On Tuesday, April 25, 2017 at 5:09:50 PM UTC-7, Justin Pearson wrote: > >

[beagleboard] Re: PRU and CPU driven by different oscillators?

Well, best way is to read the schematic. (BBB Rev C schematic, dated March 21, 2014) 24 MHz Sitara clock crystal is on upper left of page 3, hooked to main oscillator I/O. There is also a 32 kHz crystal shown there for the Real Time Clock. The 25 MHz crystal is on page 9, hooked to the LAN8710,

[beagleboard] Re: PRU and CPU driven by different oscillators?

Thanks Graham. Follow-up questions: 1. Where exactly did you find this information? I looked through the TRM and SRM but couldn't find anything definitive. 2. Is the 200-MHz PRU driven from the same 24 MHz oscillator that drives the CPU? If so, is it correct that the PRU cycle counter

[beagleboard] Re: PRU and CPU driven by different oscillators?

The CPU in a BBB runs from a 24 MHz Oscillator. There is a 25 MHz oscillator on the board, but that is for the Ethernet. --- Graham == On Tuesday, April 25, 2017 at 7:09:50 PM UTC-5, Justin Pearson wrote: > > How can I find out whether the PRU and CPU are driven by the same > oscillator?