Or you can always access them with /dev/mem mmap without dumping Linux. Sent from my iPhone
> On Aug 19, 2014, at 9:32 PM, [email protected] wrote: > > Am Dienstag, 19. August 2014 04:40:43 UTC+2 schrieb john3909: >> >> Well, that is because you are trying to access the GPIO from user space. If >> you wanted to access the GPIO from kernel space, you would use a similar >> approach to what you did on your smaller processors. The only difference >> would be that each pin supports several functions which are defined by Mode >> 0 through 7. To use a pin for GPIO, you would use Mode 7. Also, the >> processor has a set register and a clear register so that you don't have to >> disable interrupts during a real/modify/write. One other approach is to use >> mmap so that you can access the processor registers in user space for GPIO >> operations or as others have proposed, use the PRU to control GPIO. > An other approach would be to drop Linux OS completely and to have your own > (StarterWare-based) firmware running on the board. With it's standard timers > you can have a output frequency of up to 2 MHz (when doing it out of an ISR > with some bit-banging code) or up to 100 MHz (when bit-banging using > PRU-code). > > -- > 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/d/optout. -- 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/d/optout.
