Hi Mark, thanks you very much for the quick response. Going to post the ASM. Looking Forward. Kasimir ...
'Mark Lazarewicz' via BeagleBoard <beagleboard@googlegroups.com> schrieb am Mi., 12. Mai 2021, 17:55: > The memory access will add some cycle post your assembler code with > comments you're correct it doesn't make sense maybe someone will see the > issues. The PRU labs discuss measuring cycle times in CCS if you have JTAG > but toggle a GPIO and measure with a scope is probably easier. > > > > > Sent from Yahoo Mail on Android > <https://go.onelink.me/107872968?pid=InProduct&c=Global_Internal_YGrowth_AndroidEmailSig__AndroidUsers&af_wl=ym&af_sub1=Internal&af_sub2=Global_YGrowth&af_sub3=EmailSignature> > > On Wed, May 12, 2021 at 8:40 AM, Kasimir > <moritzdolgesh...@gmail.com> wrote: > Hi, > I'm working on a sine - triangle modulator, is running on BeagleBone black > / PRU 1. > On Linux/Arm I calculate the pattern for one period in form of a data > structure > pattern to output and time to the next event. > Output is PRU 1 __R30 bit 0, 1, 2, 3 ( 4 only for debug reasons, > oscilloscope trigger ) > It works .... but I'm not surprised about the speed. > The output loop of the PRU is written in some lines of ASM. > Frequencies: triangle should be 400kHz, better 800kHz, > sine wave is between 20kHz and 100kHz > Beaglebone has to drive a high speed GaN H-Bridge. > > The datatransport and handshake between Linux and PRU works fine. > A C-Program on PRU is watching for new data. Then the new data ( > pattern-time structure ) > are copied into local ram, to get the best speed ( lowest latency ). > If the data are stored in local ram, the assembler program is called, to > output the given pattern. First the arguments are saved in registers, > then the output starts in a loop. > Pick up pattern from local RAM, and output, > feed delay loop from local RAM, > delay loop, > update index register, > check for possible new data, > if not, back to the top, output next period. > > What I said ... it works. But with cycle time of 5nsec ( 1/200MHz ) and 1 > cycle for most of the (ASM) instructions, I can't see the speed. > > So there is something wrong in my setup or code. > If somebody would like to help debugging, let me know. > Sources with Makefile etc are available. > > All based on latest Debian image, all udates are installed, HDMI is off. > > So, let me know, think it makes only sense to upload that stuff in case > there is really > somebody able to help on that. > > Thanks in advance > Kasimir > > -- > 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 beagleboard+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/beagleboard/e9fe59e9-e00d-476e-99e2-6b85a90695d2n%40googlegroups.com > <https://groups.google.com/d/msgid/beagleboard/e9fe59e9-e00d-476e-99e2-6b85a90695d2n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > -- > 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/EvWTZ1wM8zQ/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > beagleboard+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/beagleboard/474549500.1653123.1620834888085%40mail.yahoo.com > <https://groups.google.com/d/msgid/beagleboard/474549500.1653123.1620834888085%40mail.yahoo.com?utm_medium=email&utm_source=footer> > . > -- 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 beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/CAHjW%3DhfM8ZHObAkM4ZrWtQNcxgByd0gGC8YqVvpDURnkF9LgOw%40mail.gmail.com.
