heh, sorry the link . . https://briancode.wordpress.com/2015/01/06/working-with-pwm-on-a-beaglebone-black/
On Wed, Jul 27, 2016 at 5:42 AM, William Hermans <[email protected]> wrote: > >> - you say that I still have to manually export pwm0 and pwm1. You >> mean after mounting your cape, I will have to write a 0 and 1 into the >> export file of the pwmchip<number> directories in /sys/class/pwm? >> >> Yes. > > - Also which Chip corresponds to which ehrpwm? > > This site has a table most of the way down that explains it. However do > keep in mind that it's outdated material, and that now we only have pwm0, > and pwm 1 per module. No, pwm0, pwm1, pwm2, pwm3, etc. Also the pwm > directories will no longer show in /sys/class/pwm, but will now show in > /sys/class/pwm/pwmchipX where X is the chip number. > > - And last but not least, what is the unit of duty_cycle and period? > Is it ns? > > I'm not 100% sure, but ns sounds reasonable. However, I'm not sure the > time period matters so much, as duty_cycle is a percentage of period. So in > our circuit here, which is reverse logic. A period of 2000 with a > duty_cycle of 2000 would be 100% duty_cycle. BUt I was just driving LEDs > with it, not a stepper motor or anything period critical. > > Anyway, you can always hook the output up to a scope . . . > -- 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/CALHSORorjcokyaf%3DXV4ZWnV%2B-QkQMz_2cs%2B6T%3DF%2BTnj7qRwKFg%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
