On 10/8/2014 10:56 PM, Ray Madigan wrote: > I can't thank you enough for your help. Every response is at least another > two day learning activity. I just wish I didn't have to work to pay the > bills. > > I went back to see what I did and it turns out I misspelled the name of the > dtbo file that I was using so there is no wonder it didn't work. > Now I get an error that the file exists when I: > > echo pru_enable > /sys/devices/bone_capemgr.8/slots > > echo: write error: File exists > prussdrv_open open failed > > so I guess I have more to learn :(
The errors from capemgr are really cryptic. You'll typically see "File exists" when something you're trying to add to the device tree is already in use. There may be slightly more information in dmesg or the kernel log. Also note it is not really possible to unload a device-tree overlay, so testing is a cycle of boot - test - shutdown. :( > What I am really trying to do is learn how to work with this device. > This activity is to learn to write to a set of 9 or 10 pins, 8 data and one > enable or 2 handshake. > > My next step is to read fro a set of 9 or 10 pins, 8 for data and one for > write enable or 2 for a handshake. > > So: > > If I add your desired pinmux settings to a custom PRU overlay based off of > one of the BB-BONE-PRU overlays provided with the standard kernel. What > would be the limitations? If you make a custom overlay and "hard-code" the pins you want to the desired mode, the limitation is from then on you won't be able to change them (without rebooting to unload your custom overlay). If you use the pinmux-helper as is done in the universal overlay, you can switch between the available modes at run-time (via the generated sysfs entries). -- 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/d/optout.
