BigChris Posted May 2, 2017 Posted May 2, 2017 I want to use a shutdown button to make a secure shutdown with the nanopi neo air. But i am completly lost how it works. I don't find out, which GPIO's i can use for a script. And if i need a puuldown or not. Can somebody help me? Thanks Chris 1
BigChris Posted May 3, 2017 Author Posted May 3, 2017 I think i answer myself I am to stupid to do it like i want, with python. But, shell scripts work everywhere an i understand it in most cases. So, here is an solution for my Problem. I use PIN 18, which Linux GPIO is 201. I pot a pullup resistor (10kOhm) to PIN 17 - 3,3V. After this, i configure the PIN18. echo 201 > /sys/class/gpio/export echo "in" > /sys/class/gpio/gpio201/direction Now i can check the value cat /sys/class/gpio/gpio201/value The answer should be 1. If now the PIN18 is shorted to PIN 20 (GND), the answer is 0. A little script does it for me: #!/bin/sh BUTTON=201 # shutdown button echo "$BUTTON" > /sys/class/gpio/export echo "in" > /sys/class/gpio/gpio$BUTTON/direction while true ; do data=`cat /sys/class/gpio/gpio$BUTTON/value` if [ "$data" -eq "0" ] ; then shutdown -h now else cnt=0 fi done 1
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