Step 9 – Reconnect the power running to the Proto Board.
Step 10 - The “HolidayLightShow” script is already monitoring for changes in light
levels on the Proto Board (sneaky, I know). However, the script includes an “auto-
calibration” capability and since we have not “calibrated” the sensor yet, no values will
be acted upon.
Place your finger over the photo-cell to represent “complete darkness”. This will give the
script a max reading for calibration. Now, if you pull your hand away, the sensor will be
reading the relative darkness.
Step 11 – Let’s start a Christmas light show.
Hold your hand close to the sensor. The red and green LEDs will begin to flash once
your hand casts a dark enough shadow over the photo cell.
Look over at the SNAPstick. You will notice that the green and red LEDs are lit up as
well. The Proto Board has communicated the change in sensor status over the air to the
neighboring device to extend the Christmas show.
Aside: Sometimes holding your finger close to the sensor will trigger it twice. If you see
the orange and red LEDs instead, you can move your hand away and then close again to
transition back to the green and red lights.
You can change the trigger point (light-intensity value) at which the script begins or
changes the light show using the node’s setThreshold () function in Portal. (The default
value is 85).
Step 12 – Time to change the season.
Move your hand away and then back to hovering over the sensor again. A Halloween
light show (orange and red LEDs) will begin to flash. As before, the Proto Board has
wirelessly communicated the message to change the light pattern to the SNAPstick as
well.
Oh, one final thing: the button on the bottom of the Proto Board will turn off the lights, or
you can execute the lightsOff () function on the Proto Board using Portal.
Success! We now have a device that will sense when the sun goes down and begin a
Christmas light show one night and a Halloween light show the next.
EK2100 Users Guide-v1.5
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