8 switches of GPIO on Zedboard

Hi
I'm using petalinux 2014.4 and used zedboard pre-defined .hdf. GPIO138 ~ 145 should be the pin connected to the switch. I did following on UART:
echo 138 > /sys/class/gpio/export
echo in > /sys/class/gpio/gpio138/direction

Then I tried to read /sys/class/gpio/gpio138/value after I flip the switch(all 8s), but the value seems always 1.

Anybody knows did I configure the connect the pins for 8 switches?

Thanks

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0 bhfletcher over 9 years ago

What do you get prior to issuing the echo for
ls /sys/class/gpio/
?

How did you know the offset was 138? The switches themselves will also have an offset based on their GPIO number. Did you account for the fact that the 8 switches are connected through EMIO?

Bryan
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0 cascade99 over 9 years ago in reply to bhfletcher

I figured it out that 8 switches are GPIO117 ~ 124, I flipped the switch, value changed.
Thanks
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0 cascade99 over 9 years ago in reply to bhfletcher

I figured it out that 8 switches are GPIO117 ~ 124, I flipped the switch, value changed.
Thanks
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