Let's blink the LED.

1. 1
Raspberry Pi Tutorial #1
- Blink the LED -
Dong Ho Son
POSTECH
Pohang, Korea
donghoson@postech.ac.kr

2. 2
Turning on the LED - Overview
 Necessary Components
• Raspberry Pi
• 1 x Breadboard
• 1 x red LED
• 1 x Resistor
• Jumper cables
Anode
Cathode
Power rails
Terminal strips

3. 3
Turning on the LED – Circuit Configuration
 Ground pin  the cathode of the LED
 The anode of the LED  a ballast
resistor
 The ballast resistor  the pin GPIO 17
Ground
GPIO 17
AnodeCathode

4. 4
Turning on the LED - Python
 Import RPi.GPIO as GPIO
• Import Python GPIO module
 GPIO.output(pin, GPIO.HIGH)
• Turn on the LED
 time.sleep(1)
• Delay for 1 second
 GPIO.output(pin, GPIO.LOW)
• Turn off the LED
 GPIO.setmode(GPIO.BCM)
 GPIO.setup(17, GPIO.OUT)
• Select GPIO #17 as output pin

5. 5
Turning on the LED – Program Writing & Execution
 Python Programming using Text editors
• Desktop Graphical Editors – LEAFPAD, IDLE, GVIM
• Command-Line Editors – NANO, VI, VIM, EMACS
 Python Programming Interpreter
• Built-in Interpreter provided in Raspbian
• Command line execution: “$ python program.name”

6. 6
Turning on the LED - Result
 The LED is blinked!
Ground
GPIO 17