pilights - fun scripts for controlling LEDs via Raspberry Pi

This is a simple collection of shell scripts designed to make it easy for children to play with a set of LEDs attached to a Raspberry Pi via GPIO.

Usage

The main configuration and setup is in the pilights file, and assumes a default layout of 3 LEDs attached like this:

GPIO17  Red
GPIO18  Yellow
GPIO21  Green

There is also optional support for a second set of lights:

GPIO22  Red2
GPIO23  Yellow2
GPIO24  Green2

2 functions are supplied, turn and wait:

turn <light> <on|off>
wait <seconds>

So a simple script to turn the red light on and then off again 2 seconds later would be:

. ./pilights

turn red on
wait 2
turn red off

Both functions are designed to be case-insensitive and also allow additional arguments for optional clarity. The above could instead be written like this:

TURN RED LIGHT ON
WAIT 2 SECONDS 
TURN RED LIGHT OFF

for that retro feel ;)

There is also a simple alias for a 'while true' loop:

repeat
  turn red on
  wait 0.2
  turn red off
  wait 0.2
done

Example Scripts

A number of example scripts are provided.

• flashlight flashes the red LED.
• flashlights flashes the red, yellow, and green LEDs.
• flashlights2 flashes both sets of red, yellow, and green LEDs.
• trafficlights runs a traffic light simulation with the first set of LEDs.
• trafficlights2 runs a full traffic light simulation with both sets of LEDs.

You are encouraged to play with these scripts and edit them to observe the change in behaviour.

Have fun!