On Thu, Nov 15, 2018 at 9:38 AM Bill Bitner <[email protected]> wrote: > > Hi Fred! > > What version of the linux kernel are you using? It makes a large > difference as the kernel interfaces have changed. > My experience may not apply to your's but I can share it with you. > I have a beagle board black. The board booted fine and then I installed > the latest at the time "debian 9.4 lxqt". The board booted fine. The PRU > compilers where *already* installed. However, I could not access the PRU > from the device tree. From > https://markayoder.github.io/PRUCookbook/ > In Mark's excellent guide, I was able to see the following instructions > in the Makefile. > """ > # Lookup PRU by address > ifeq ($(PRUN),0) > PRU_ADDR=4a334000 > endif > ifeq ($(PRUN),1) > PRU_ADDR=4a338000 > endif > > PRU_DIR=$(wildcard > /sys/devices/platform/ocp/4a32600*.pruss-soc-bus/4a300000.pruss/$(PRU_ADDR).*/remoteproc/remoteproc*) > """ > > I could not see these addresses despite modifications to the uEnv.txt file. > I finally discovered that despite booting from the SD card, > the boot process would use information from the built-in flash chip. Once > I zeroed out the on-board flash chip, (using the following) > sudo dd if=/dev/zero of=/dev/mmcblk1 count=1 seek=1 bs=128k > I could make changes to the uEnv.txt file and everything started working as > one would expect.
Typically (unless the bootloader on the microSD also tries to load from eMMC), you can hold down the BOOT/SD/S2 button when applying power (release right after applying power) and it will force the bootloader on the eMMC to be ignored. > > Bill Bitner > > On Wed, Nov 14, 2018 at 8:19 PM <[email protected]> wrote: >> >> Hi guys, >> >> I am having some problems in getting started with PRU. >> >> So, first of all, I installed one PRU compiler (CSS) (I follow this article: >> http://processors.wiki.ti.com/index.php/PRU_Training:_Hands-on_Labs >> >> After having the compiled the file, and from what I've read throughout the >> internet, I thought that in order to run a program into the PRU I should >> simply do: >> >> - cp mycode.out /lib/firmware/am335x-pru0-fw >> - echo 'start' > /sys/class/remoteproc/remoteproc1/state >> >> However, If I try it with a code to blink a led it does nothing (example of >> the code for blinking a LED above). >> >> volatile register unsigned int __R30; >> >> int main(void) { >> __R30 = SET_MASK; >> >> while(1) { >> __R30 = __R30 & ~(SET_MASK); >> __delay_cycles(100000000); // half-second delay >> } >> } >> >> I've also tried to follow this tutorial: >> http://www.righto.com/2016/09/how-to-run-c-programs-on-beaglebones.html >> and I get an error when I do: ./loader text.bin data.bin, it says an error >> message of "prudrv failed to open". But I can't quit understand what that >> program does. >> >> Can anyone tell me what am I doing wrong ? >> >> Thanks you very much, >> Fred Gomes >> >> -- >> 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/467fd871-1c67-489b-9fad-82104bfd7ba2%40googlegroups.com. >> 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]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/beagleboard/CAOYP4di%2BoF5UDX2pv1yd9A5FGyogt31yi_ekXUokFjfxYMq%3DFA%40mail.gmail.com. > 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]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/CA%2BT6QPn8uYRZr-W%3DYm8FBtp_2sZbghR%3Du3KiwuUnsOq_SvRc8Q%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
