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+====== Pi Traffic Light Python Example ======
+This is an example of how to use Python to control the LEDs of the Pi Traffic light http://lowvoltagelabs.com/products/pi-traffic/
+See the [[pitrafficlight|hardware installation]] page for information on installing the Pi Traffic light on the Raspberry Pi.
+{{:pi_traffic_installed_yellow_led_on.jpg?direct&300|}}
+==== Software Setup ====
+If the Python RPi.GPIO module is not already installed go to https://pypi.python.org/pypi/RPi.GPIO to download the module.
+==== LED control ====
+The three LEDs are setup in such a way that a high voltage turns the LEDs ON. In terms that the Python module understands that means to turn on an LED you set the output pin to True.
+The LEDs are connected to the following pins:
+  * pin 9 = Red LED
+  * pin 10 = Yellow LED
+  * pin 11 = Green LED
+In Python the pins first need to be setup as outputs then set to True to turn the LED on or False to turn the LED off.
+  # Pin Setup:
+  GPIO.setmode(GPIO.BCM)   # Broadcom pin-numbering scheme. This uses the pin numbers that match the pin numbers on the Pi Traffic light.
+  GPIO.setup(9, GPIO.OUT)   # Red LED pin set as output
+  # Set the pin HIGH
+  GPIO.output(9, True)  # Turns on the Red LED
+  # Set the pin LOW
+  GPIO.output(9, False)  # Turns off the Red LED
+To use the Yellow and Green LEDs first set those pins to output:
+  GPIO.setup(10, GPIO.OUT)   # Yellow LED pin set as output
+  GPIO.setup(11, GPIO.OUT)   # Green LED pin set as output
+Then use the GPIO.output statement to set the pins to True or False.

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