P8_13 is working for me as a PWM output, and I am using the Adafruit BBIO library. I’m using the latest image with LXQT (Debian 9.9 I believe). Randy
On Thursday, January 14, 2021 at 8:28:34 PM UTC-6 [email protected] wrote: > OK, I rechecked and only Pin 8_13 is not working; the other three PWM pins > are good using Adafruit.PWM. Pin 8_13 does respond to GPIO.HIGH and > GPIO.LOW, so I don’t think I’ve damaged the hardware. Who knows what I > have managed to do to the /sys/class files. If it doesn’t clear up on > restart, I will reinstall the image. Of course 8_13 is the one I was > planning to use, but I can just as well wire something to 8_19 for now. > > Thanks for the help. > > -Steve > > > On Jan 14, 2021, at 8:00 PM, jonnymo <[email protected]> wrote: > > The SpreadSheet at the following link will show you which pins on the BB > Black can be set for PWM. > > > https://docs.google.com/spreadsheets/d/1fE-AsDZvJ-bBwzNBj1_sPDrutvEvsmARqFwvbw_HkrE/edit#gid=1518010293 > > As far as the Adafruit BBIO libs, have you gone through the example at the > Adafruit site? > > https://learn.adafruit.com/setting-up-io-python-library-on-beaglebone-black/pwm > > If this is not working, could you provide any errors or output of the > issue you are seeing? > > The output of the following might be helpful: > * /opt/scripts/tools/version.sh* > > Cheers, > > Jon > > > On Thu, Jan 14, 2021 at 4:42 PM Steve Lentz <[email protected]> wrote: > >> Black. BeagleBoard.org <http://beagleboard.org/> Debian Buster IoT >> Image 2020-04-06. >> >> FWIW, the Adafruit libraries let me control the pins as GPIO. >> >> >> TY, >> -Steve >> >> On Jan 14, 2021, at 7:02 PM, jonnymo <[email protected]> wrote: >> >> Which BeagleBoard are you using? >> >> Jon >> >> On Thu, Jan 14, 2021 at 2:51 PM [email protected] <[email protected]> >> wrote: >> >>> OK, I want to generate a PWM signal to send to a motor controller. This >>> is simply to communicate the desired speed, the motor controller will do >>> all the heavy lifting. >>> >>> Unfortunately, the Adafruit_BBIO libraries appear broken and bonescript >>> doesn't seem any better. >>> >>> After digging through Google results I found myself in /sys/class/pwm/ >>> using echo to write values into various files and through pure dumb luck >>> was able to get a 2 Khz square wave up on a scope and change its duty >>> cycle. So at least my set up seems to be working at some level. >>> >>> However, I feel I am missing a bunch of information. Which pwmchip >>> exports to which pwm-X:X and corresponds to which pin? "duty_cycle" is not >>> really duty cycle, it is nanoseconds high. I can't change the period, even >>> to sensible values like 250000 or 1000000. Some of the information on >>> Stack Exchange is worrying, will pwm-4:0 always correspond to P9_14 or can >>> this change on boot? >>> >>> Is there a way to restore the functionality of the Adafruit BBIO >>> libraries, short of waiting for an update? I did pip3 install -U. >>> Requirement already satisfied: Adafruit_BBIO in >>> /usr/local/lib/python3.7/dist-packages (1.2.0) >>> >>> If that's not possible, is there any documentation on how the >>> /sys/class/pwm is intended to function? >>> >>> Thank you, >>> -Steve Lentz >>> >>> -- >>> 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]. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/beagleboard/08130fba-0f75-464a-9041-d66a1c3a8cacn%40googlegroups.com >>> >>> <https://groups.google.com/d/msgid/beagleboard/08130fba-0f75-464a-9041-d66a1c3a8cacn%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 the Google Groups >> "BeagleBoard" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/beagleboard/CAG99bkoUYXmrUU%2BwtoQnXTYAd3Uq6SAXsTFskbZ-75%2ByvAX3eQ%40mail.gmail.com >> >> <https://groups.google.com/d/msgid/beagleboard/CAG99bkoUYXmrUU%2BwtoQnXTYAd3Uq6SAXsTFskbZ-75%2ByvAX3eQ%40mail.gmail.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 [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/beagleboard/44AF4518-7FEA-4331-9E61-5D442D484D20%40gmail.com >> >> <https://groups.google.com/d/msgid/beagleboard/44AF4518-7FEA-4331-9E61-5D442D484D20%40gmail.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 [email protected]. > > To view this discussion on the web visit > https://groups.google.com/d/msgid/beagleboard/CAG99bkr3Uo18Mx57p-m2ec2bfi0A%2BKjYMJYNb-bd5sMfKNpRzg%40mail.gmail.com > > <https://groups.google.com/d/msgid/beagleboard/CAG99bkr3Uo18Mx57p-m2ec2bfi0A%2BKjYMJYNb-bd5sMfKNpRzg%40mail.gmail.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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/8d4b5048-1469-4557-bafa-1c8680aa39b1n%40googlegroups.com.
