30 lines
841 B
Bash
30 lines
841 B
Bash
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#!/bin/bash
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# run in background, install into inittab, anything goes
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# example for inittab:
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# P0:2345:respawn:/root/buttonscanner.sh
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COUNTER=/home/pi/website/counter.txt
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WiringPIN=18 # physical pin 12
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PATH=/bin:/usr/bin:/usr/local/bin
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gpio -g mode $WiringPIN in # set to input mode
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gpio -g mode $WiringPIN down # set internal pulldown
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echo "Sensor scanner starting"
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while true
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do
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echo "scanning..."
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gpio -g wfi $WiringPIN falling # wait for detection (uses no cpu, but interrupt)
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echo "got event"
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gpio -g read $WiringPIN
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if [ $(gpio -g read $WiringPIN) -eq 0 ]
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then
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counter="$(head "$COUNTER")"
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counter=$((counter+1))
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cp -p "$COUNTER" "$COUNTER".new
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echo "$counter" > "$COUNTER".new
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mv "$COUNTER".new "$COUNTER"
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echo "counter is now $counter"
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echo "sleeping for 10s"
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sleep 10
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fi
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done
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