Joshua Parrish

GPIO access

Discussion created by Joshua Parrish on Sep 27, 2011
Latest reply on Mar 10, 2013 by Winston Rodrigues

I was hoping to get some help with the imx53 loco board. 

I can't get GPIO access to work. 

 

I've set up the /sys/class sysfs support in the system using a new kernel. 

 

With the ubuntu micro sd shipped with the qsb board (with newly flashed kernel)

I get permission denied when I try to echo 12 > /sys/class/gpio/export

 

With an ltib made rootfs and kernel 

I get all the way through 

echo 12 > /sys/class/gpio/export

echo out > /sys/class/gpio/gpio12/direction

echo 1 > /sys/class/gpio/gpio12/value

 

but the value doesn't change on the pin nor the actual file "value"

>cat /sys/class/gpio/gpio12/value

>0

I can change the direction just fine, however the value still eludes me. 

I've also tried this on different ports, still nothing works. 

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