Flash Raspberry Pi LED in Response to Input
This example shows how to flash the on-board LED when you press a button that is connected to a GPIO pin.
Excessive voltage and current can damage the Raspberry Pi® hardware. Observe the manufacturer’s precautions for handling the Raspberry Pi hardware and connecting it to other devices. For more information, see https://www.raspberrypi.org/technical-help-and-resource-documents.
Using a breadboard, set up the following circuit:
Connect one of the +3.3V pins on the GPIO header to a button.
Connect pin 23 on the GPIO header to a 220 or 330 Ohm resistor.
Connect the unconnected ends of the button and resistor to each other.
showLEDs to show an illustration that identifies each
Run the code and press the button. The button closes the circuit between the +3.3V pin and
pin 23. When
readDigitalPin detects the raised voltage,
toggles the LED on and off ten
for ii = 1:100 buttonPressed = readDigitalPin(mypi,23) if buttonPressed for jj = 1:10 writeLED(mypi,'led0',1) pause(0.05) writeLED(mypi,'led0',0) pause(0.05) end end pause(0.1) end