On 10/18/2013 5:22 PM, Paul Tan wrote: > In case anyone's wondering why I'm trying to get really short pulses, I'm > trying to connect an iGaging DRO slides to a BeagleBone Black (yeah, I'm > trying to CNC my lathe using a DRO closed loop servo with my Dual Motor > Controller Capes). Scoping out my iGaging DRO, I found that the builtin > controller uses 24uS pulses with a 128uS duty cycle. I'm working off of > Yuriy's work on the Arduino (http://www.yuriystoys.com/p/android-dro.html), > but trying it on the BeagleBone.
For fairly short duration pulses like that, you may want to consider using the PRU to handle generating the pulses. It looks like the stuff you're working from is already divided between the UI (handled by Linux) and the low-level comms (handled by an Arduino). Basically, you can migrate the Arduino stuff to the PRU and probably have less overall hassle. I have some example code for step/dir pulses and PWM using the PRU driving GPIO pins as part of LinuxCNC. I also have some timing details on PRU read and write latency when talking to the GPIO registers: https://github.com/cdsteinkuehler/linuxcnc/blob/MachineKit-ubc/src/hal/drivers/hal_pru_generic/pru_generic.p#L135 -- Charles Steinkuehler [email protected] -- 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]. For more options, visit https://groups.google.com/groups/opt_out.
