rtc-mon

#!/bin/bash
BATSYS="/sys/devices/platform/soc*/soc*:rpi_rtc/rtc/rtc0/battery_voltage"
LOWV="275"
HIGHV="300"
CHGSYS="/sys/devices/platform/soc*/soc*:rpi_rtc/rtc/rtc0/charging_voltage"
CFGF="/boot/config.txt /boot/tryboot.txt"
DTP="dtparam=rtc_bbat_vchg=3000000"
getbatv() { 
	cut -c1-3 ${BATSYS} 
} 
chgon() {
	sed -i "s/#${DTP}/${DTP}/" ${CFGF}
	sleep 30
	systemctl reboot
}
chgoff() {
	sed -i "s/${DTP}/#${DTP}/" ${CFGF}
	sleep 30
	systemctl reboot
}
if [ "${UID}" -ne 0 ]; then
	exec sudo $0 $@
fi
if [ "$(getbatv)" -le "${LOWV}" ]; then 
	#ENABLE CHARGE, reboot 11
	 echo "Low rtc battery, rebooting to enable charging"
	 chgon
elif [ "$(getbatv)" -ge "${HIGHV}" ]; then 
	if [ $(cat ${CHGSYS}) -ne 0 ]; then
		#stop charge, reboot
		echo "Rtc battery charged, rebooting to stop"
		chgoff
	else
	echo "Battery high charge but not charging"
	fi
else
	echo "Battery between high and low level"
	echo -n "voltage: "
	getbatv
	echo -n "Charge voltage: "
	cut -c1-3 ${CHGSYS}
fi