Initial commit

battery_status_led.service

@@ -0,0 +1,7 @@
+[Unit]
+Description=Battery monitoring on CapsLock LED
+
+[Service]
+ExecStart="/usr/bin/battery_led.sh"
+Type=idle
+

battery_status_led.sh

@@ -0,0 +1,51 @@
+#!/bin/bash
+
+# limits in percentages
+LOW=10 # flip LED every 2s
+CRIT=5 # flip led every 0.5s
+
+BAT_FULL=`cat /sys/class/power_supply/BAT0/energy_full_design`
+CAPSLOCK_LED=`cat /sys/class/leds/input4\:\:capslock/brightness`
+
+LED_DEV=/sys/class/leds/input4\:\:capslock/brightness
+
+
+CNT=0
+while :
+do
+	# If charging, sleep 1m, then restart the cycle
+	STATUS=`cat /sys/class/power_supply/BAT0/status`
+	if [ $STATUS == "Charging" ] ; then
+		echo 0 > $LED_DEV
+		sleep 1m
+		continue
+	fi
+
+	BAT_NOW=`cat /sys/class/power_supply/BAT0/energy_now`
+	BAT_PCT=$(($BAT_NOW * 100 / $BAT_FULL))
+
+	# If battery has more than >10% left, sleep 1m then restart the cycle
+	if (($BAT_PCT > $LOW )) ; then
+		sleep 1m
+		continue
+	fi
+
+	sleep 0.5s
+	CNT=$((CNT+1))
+
+	# If battery <5% (crytical) flip capslock LED every 0.5s
+	if (( $BAT_PCT <= $CRIT )) ; then
+		CAPSLOCK_LED=$((1 ^ $CAPSLOCK_LED))
+		echo $CAPSLOCK_LED > $LED_DEV 
+	# If battery is on low, but not crytical, flip LED every 4th 0.5s (2s)
+	elif (( $BAT_PCT <= $LOW )) && (( $CNT % 4 == 1 )) ; then
+		CAPSLOCK_LED=$((1 ^ $CAPSLOCK_LED))
+		echo $CAPSLOCK_LED > $LED_DEV 
+	fi
+
+	# not sure if i need this:
+	if (( $CNT > 100000 )) ; then
+		CNT=1
+	fi
+done
+