On Friday, 3 February 2017 13:17:20 UTC+1, Hugh Frater wrote: > > However when I 'cat position' in each of the relevant sys entries (having > moved my encoder A/B lines to the relevant pins each time), I get a > changing value but it isn't meaningful. Am I missing something, or is it > more likely that I've blown up the inputs? I did power on the servo drive > (that was connected to the 26lv32 breakout board) by accident when the BBB > wasn't powered up. >
Verify the ports are working correctly in GPIO mode first. > Do I have to mess about with config-pin for each of the eQEP inputs, or > should loading the relevant dtbo file for the eQEP module (0, 1 2 etc) set > up the pins for me? > When using overlays they should setup pinmux correctly. config-pin uses cape-universal (which conflicts with pretty much any overlay). Beware that eQEP 2 has two pinmux options, for which two separate overlays exist. Double-check pinmux e.g. using my show-pins utility <https://github.com/mvduin/bbb-pin-utils>. Also, it looks like the driver isn't configured correctly <https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/bone_eqep2b-00A0.dts#L62-L73> for your purposes by the overlay, so you may need to adjust that. The eqep driver is known to have buggy power management, try disabling automatic runtime pm using: for i in /sys/bus/platform/drivers/eqep/*/power/control; do echo enabled >"$i"; done (Note: I personally don't actually have any experience with the eqep driver, I've only used the eqep modules via uio. I actually made a python example <https://github.com/mvduin/py-uio/blob/master/qep-test.py> for that, although it's unmaintained since I came to the conclusion I don't actually like python.) Matthijs -- 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/7ff174d2-d920-4934-b7b3-9da58390774e%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
