Script for a coloring / cooling system temperature-dependent for Raspberry PI

PICool.sh

#!/bin/bash

# @Author: Horloge-Skynet
# @Created: 2014-01-26
# @Created: 2020-04-14
# @Brief: Script for a coloring / cooling system temperature-dependent for Raspberry PI

## GPIO path ##
GPIO_PATH=/usr/local/bin/gpio

## Log file path ##
LOG_FILE_PATH=/root/temperatures.log

## Pin status ##
ON=1
OFF=0

## Pin outputs ##
RED_PIN=4
GREEN_PIN=5
FAN_PIN=6

## What time slot do you want ? (Here: from 6:30 AM to 10:30 PM) ##
TIME_START='0630'
TIME_STOP='2230'

## A temperature threshold for LED coloring, and cooling system enabling ##
THRESHOLD='38'

## A temperature limit for cooling system enabling (even if this is the night and you're asleep !) ##
LIMIT='50'


## If the system has just started ('uptime' < 2 * 60 seconds), let's define ours GPIO pin modes ##
if [[ $(cut -d . -f 1 < /proc/uptime) -lt 120 ]]; then
	"$GPIO_PATH" mode ${RED_PIN} out    # Red LED
	"$GPIO_PATH" mode ${GREEN_PIN} out  # Green LED
	"$GPIO_PATH" mode ${FAN_PIN} out    # Fan
fi


## Let's get some temperatures values from the system ##
cpu_temp="$(cat /sys/class/thermal/thermal_zone0/temp)"; cpu_temp=$((cpu_temp / 1000))
gpu_temp=$(/opt/vc/bin/vcgencmd measure_temp); gpu_temp=${gpu_temp:5:2}

if [[ ${cpu_temp} -gt ${THRESHOLD} || ${gpu_temp} -gt ${THRESHOLD} ]]; then
	"$GPIO_PATH" write ${GREEN_PIN} ${OFF}  # Shutdown the green LED
	"$GPIO_PATH" write ${RED_PIN} ${ON}     # Light up the red LED

	## Get the current time ##
	currentTime=$(date +%H%M)

	## If we're in the time slot, or if the temperature has reached the maximum limit, let's enable the cooling system ##
	if [[ ($((10#${currentTime})) -gt $((10#${TIME_START})) && $((10#${currentTime})) -lt $((10#${TIME_STOP}))) || (${cpu_temp} -gt ${LIMIT} || ${gpu_temp} -gt ${LIMIT}) ]]; then
		"$GPIO_PATH" write ${FAN_PIN} ${ON}  # Switch on the fan
	fi

	# Save the data into a log file
	echo -e "${currentTime} --> CPU: ${cpu_temp} \\xc2\\xb0C - ${gpu_temp} \\xc2\\xb0C" >> "$LOG_FILE_PATH"
else
	"$GPIO_PATH" write ${FAN_PIN} ${OFF}   # Switch off the fan
	"$GPIO_PATH" write ${RED_PIN} ${OFF}   # Shutdown the red LED
	"$GPIO_PATH" write ${GREEN_PIN} ${ON}  # Light up the green LED
fi