diff --git a/displaytest.py b/displaytest.py
index a64b786..4c789d0 100644
--- a/displaytest.py
+++ b/displaytest.py
@@ -1,13 +1,23 @@
 #! /usr/bin/python3
 # -*- coding: utf8 -*-
 
+# load needed modules from luma
 from luma.core.interface.serial import i2c, spi
 from luma.core.render import canvas
 from luma.oled.device import sh1106
 from luma.core import lib
 
+# load needed modules from RPi.GPIO
+import RPi.GPIO as GPIO
+
+# load needed modules from PIL
 from PIL import ImageFont, ImageDraw, Image
 
+#GPIO define pins
+RST_PIN  = 25 #Reset
+CS_PIN   = 8
+DC_PIN   = 24
+
 serial = spi(device=0, port=0, bus_speed_hz = 8000000, transfer_size = 4096, gpio_DC = DC_PIN, gpio_RST = RST_PIN)
 device = sh1106(serial, rotate=2) #sh1106