diff --git a/scripts/SATA-hat.sh b/scripts/SATA-hat.sh
index ac721b9..8d879e1 100755
--- a/scripts/SATA-hat.sh
+++ b/scripts/SATA-hat.sh
@@ -1,56 +1,60 @@
 #!/bin/sh
 
-BASE_PATH=/sys/class/gpio
+BASE_PATH=/sys/class
+GPIO_PATH="$BASE_PATH"/gpio
+PWM_PATH="$BASE_PATH"/pwm
 
 # GPIO pins
 SATA0=26
 SATA1=25
+# PWM pins
 CPU_FAN=12
+HDD_FAN=13
 
 # Values
 LOW=0
 HIGH=1
 
 export_pin() {
-	if [ ! -e $BASE_PATH/gpio"$1" ]; then
-		echo "$1" >$BASE_PATH/export
-	fi
+    if [ ! -e $GPIO_PATH/gpio"$1" ]; then
+        echo "$1" >$GPIO_PATH/export
+    fi
 }
 
 unexport_pin() {
-	if [ -e $BASE_PATH/gpio"$1" ]; then
-		echo "$1" >$BASE_PATH/unexport
-	fi
+    if [ -e $GPIO_PATH/gpio"$1" ]; then
+        echo "$1" >$GPIO_PATH/unexport
+    fi
 }
 
 set_mode() {
-	export_pin "$1"
-	echo "out" >$BASE_PATH/gpio"$1"/direction
-	echo "$2" >$BASE_PATH/gpio"$1"/value
-	if [ "$3" = "clean" ]; then
-		unexport_pin "$1"
-	fi
+    export_pin "$1"
+    echo "out" >$GPIO_PATH/gpio"$1"/direction
+    echo "$2" >$GPIO_PATH/gpio"$1"/value
+    if [ "$3" = "clean" ]; then
+        unexport_pin "$1"
+    fi
 }
 
 turn_on() {
-	set_mode $SATA0 $HIGH
-	sleep 1
-	set_mode $SATA1 $HIGH
-	set_mode $CPU_FAN $LOW
+    set_mode $SATA0 $HIGH
+    sleep 1
+    set_mode $SATA1 $HIGH
+    set_mode $CPU_FAN $HIGH
 }
 
 turn_off() {
-	set_mode $SATA0 $LOW clean
-	set_mode $SATA1 $LOW clean
-	set_mode $CPU_FAN $LOW clean
+    set_mode $SATA0 $LOW clean
+    set_mode $SATA1 $LOW clean
+    set_mode $CPU_FAN $LOW clean
 }
 
 trap turn_off INT
 
 if [ "$1" = "on" ]; then
-	turn_on
+    turn_on
 else
-	turn_off
+    turn_off
 fi
 
 exit 0