Difference between revisions of "ECE497 Notes on gpio-keys"
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+ | == Timers == | ||
+ | Here's some leads on using timers. | ||
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+ | [https://groups.google.com/forum/?fromgroups#!topic/beagleboard/lCagocQaKiY%5B1-25%5D kunen.org] | ||
+ | |||
+ | == gpio-keys == | ||
I'm trying to figure out how to access the USER button on the Beagle xM. It looks like the new versions of the SD image use gpio-keys to manage gpio 4 so you can't access it via | I'm trying to figure out how to access the USER button on the Beagle xM. It looks like the new versions of the SD image use gpio-keys to manage gpio 4 so you can't access it via | ||
beagle$ '''cd /sys/class/gpio''' | beagle$ '''cd /sys/class/gpio''' |
Revision as of 12:17, 13 August 2012
Embedded Linux Class by Mark A. Yoder
Timers
Here's some leads on using timers.
gpio-keys
I'm trying to figure out how to access the USER button on the Beagle xM. It looks like the new versions of the SD image use gpio-keys to manage gpio 4 so you can't access it via
beagle$ cd /sys/class/gpio beagle$ echo 4 > export bash: echo: write error: Device or resource busy
You need to access it via evtest, but I don't see a way to do it via the shell.
References
- Here Jason suggests looking at evtest.c to learn how to access the USER button.
- Here are some details on evtest.
Embedded Linux Class by Mark A. Yoder