On Sun, Nov 5, 2017 at 1:04 AM Alek Mabry <[email protected]> wrote:
> I noticed that USR0 was blinking at a steady rate that was not 5 blinks > per second it is supposed to. > Looks like I adjusted the rate without updating the README.md. I also tried to add a mode that allows for a "decay" where the cycles between toggles gets shorter and shorter. With that mode, you can see a bit more of the power of the PRU to toggle pins quickly, although you quickly get to a point where you'd need a scope to see how fast the PRU is toggling the GPIO. > (After I ran sudo make run). There was no way to make it stop blinking > with the /sys/class/leds/ commands. > Right. Because the PRU is controlling the GPIO and not Linux, the /sys/class/leds interface wouldn't stop it from toggling. However, you might note that Linux might still set or clear the LED at times, so both Linux and the PRU can collide with each other. That's why my instructions say to set the trigger to "none". > I restarted the beaglebone and was able to control whether it did a > heartbeat/none with trigger, but after I ran "sudo make run" it did the > blinking again. > > I changed the hello-pru.c so that the INS_PER_US was 50 instead of 200 and > recompiled and it appears to be blinking four times as fast, so the PRU is > controlling the LED without having to run "sudo config-pin p9.30 pruout." > As mentioned elsewhere on this thread, p9.30 is for the PRU GPIO and the USR0 LED is controlled via an OCP GPIO. PRU GPIOs can be controlled much faster, but the LEDs aren't connected to pins that have pruout modes. My example illustrated toggling both an OCP GPIO and a PRU GPIO. PRU GPIOs can be set with registers directly in the PRU core rather than needing to write to an OCP (on-chip-peripheral) memory address. > -- > 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/0d1000a8-ffe6-4e22-979b-fb5ce1194efb%40googlegroups.com > <https://groups.google.com/d/msgid/beagleboard/0d1000a8-ffe6-4e22-979b-fb5ce1194efb%40googlegroups.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > -- https://beagleboard.org/about -- 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/CA%2BT6QPnUCtLAFixB8Lj-Ak20_DP9vs2PXBYf4nwKFVXFECWR8g%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
