Fan speed controlled by CPU temp script

Code:
#!/bin/bash
#MikeD
#Automatic fan on cpu temp

CHECK_TIME=10 #IN SEC

function pwm(){
LOOP=0
while [ $LOOP -lt $(($CHECK_TIME*75)) ]; do
        echo 1 > /sys/class/gpio/gpio82/value
        sleep $1
        echo 0 > /sys/class/gpio/gpio82/value
        sleep $2
        LOOP=$(($LOOP+1))
done
}

function fanOff()
{
echo 0 > /sys/class/gpio/gpio82/value
sleep $CHECK_TIME
}

function fanTweFiv()
{
pwm .0025 .0075
}

function fanFifty()
{
pwm .0050 .0050
}

function fanSevFiv()
{
pwm .0075 .0025
}

function fanFull()
{
echo 1 > /sys/class/gpio/gpio82/value
sleep $CHECK_TIME
}

while [ 1 ]; do
        TEMP=$(cat /sys/class/thermal/thermal_zone0/temp)

        if [ $TEMP -le 20000 ]
        then
                fanOff
        fi
        if [ $TEMP -gt 20000  -a  $TEMP -le 35000 ]
        then
                fanTweFiv
        fi

        if [ $TEMP -gt 35000 -a $TEMP -le 50000 ]
        then
                fanFifty
        fi

        if [ $TEMP -gt 50000 -a $TEMP -le 65000 ]
        then
                fanSevFiv
        fi

        if [ $TEMP -gt 65000 ]
        then
                fanFull
        fi

done