Home Hacking Projects for Geeks

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Chapter 2, Automate Your Porch Light

5. Create the script

You now have completely flexible and extensible control over your home’s

lighting. Unless you want to simply flash your lights on and off, though,

your computer doesn’t yet have the logic it needs to accomplish the original

goal of controlling the porch light based on events triggered by the motion

detector and the time of day.

To accomplish this, you’ll now create a script to listen for signals from the

motion detector, and send commands based on the time of day. This script

must be running continuously.

You’ll use the eg_cm11.plx script as the foundation for a script to turn

off the porch light. Save the script from Exhibit B as C:\homehacks\x10-

controls.pl. You can also download the script, along with any updates I’ve

made, from http://www.homehacking.com. For you hackers, the later section

“Understanding the Script” describes how the script works.

Many applications out there make it easy to edit Perl scripts. Notepad works fine,

too.

6. Run the script

To run the script, open a command prompt and switch to the directory you

saved it in (C:\homehacks, as suggested above). Then, simply type the name

of the script:

x10-controls.pl

Assuming that you’ve installed Perl and the required modules correctly, the

script will start running and continue until you press Ctrl+C. You won’t

see anything happen unt ...