A boosterpack for Texas Instruments' MSP430 Launchpad platform.
My body doesn't seem to be designed to get out of bed without loud complaints. This is especially true in the winter months, when I have to be out of bed before the sun comes up. This boosterpack is designed to help, by tickling light-sensitive cells in the eye that tell the body to wake up.
It seems so [1]. In the past two or three years, scientists have found that, in addition to the rods and cones, the eye has a third type of photoreceptor [2]. Among other things, these cells send the brain signals about when to sleep and when to wake up. They respond to blue light, the bright blue from the sky that surrounds us outdoors on a sunny day. They take "rise and shine" literally: the sun is up, the sky is blue, so wake up!
This boosterpack lets you experiment with adding a little blue light into your life, even if you are asleep in bed before sunrise, or working in a room with thick walls separating you from that lovely blue sky. It mounts 16 high-intensity LEDs, eight white and eight blue, which are controlled with an MSP430 Launchpad. The intensity of the white lights is controlled with the TA0.1 PWM pin, while the intensity of the blue lights is controlled with the TA0.2 PWM pin of the MSP430G2452 chip.
Code hosted on Github turns the boosterpack/Launchpad combination into a visual alarm clock of sorts. When the alarm "goes off," the light gradually begins to increase in intensity over the space of about half an hour. It stays on for another half hour, long enough for you to get out of bed if you're going to, then turns itself off. Four buttons along the top of the boosterpack allow you to control the lights. "On/off" does just what it says: it toggles the lights on and off. This is what you use in the morning if you want to turn the lights off without a lot of fuss. Holding down the "bright" button goes through a sequence of four brightness levels. Release the button when you get to the maximum brightness level you are comfortable with. This is the maximum intensity you will see in the morning. The "color" button works similarly: hold it down to cycle through blue light only, white light only, or both. Finally, the "alarm" button toggles the alarm indicator, a small green LED, on and off. If the indicator light is on, the alarm will go off in the morning.
The boosterpack gets its power from a 18V wall-mounted plugin power supply (wall wart). This powers four strings of four LEDs each. Each LED string is controlled with a very simple constant-current sink built from two general-purpose NPN transistors. A voltage regulator on the board generates Vcc at 3.6V for the Launchpad, so you don't have to keep the Launchpad plugged into a USB port for power. Just plug the Launchpad into the boosterpack, plug the wall wart into an outlet, and connect the two, and you're set.
Except for one thing: setting the time for the alarm to go off. I've kept the pinout of the boosterpack compatible with the 43oh OLED display ("The Terminal") available at 43oh.com. You should be able to stack the OLED boosterpack on top of this one, and use the two buttons on the OLED boosterpack to set the time and alarm. I should warn you that I haven't done this, however. You'll have to write the code yourself.
I set the time and alarm myself using the Launchpad USB port, writing out the time directly in the MSP430 code. A bit crude, I know, but this is just experimentation, after all. I have included a battery backup in the boosterpack, so that the Launchpad can maintain enough power to remember the time even when the wall wart is unplugged. That way, you can plug the Launchpad/boosterpack combination into your computer's USB port, set the time and alarm, unplug it, carry it into your bedroom, and plug it back in without losing the time. The four buttons on the boosterpack will give you enough control after that.
I set this boosterpack up in my 8-year-old's bedroom during the month of February. The first two mornings, my normally somnolent son bounded out of bed 15 minutes early, heading right into Mom and Dad's bedroom. Since then, it continues to help my son out of bed... just not in such a forceful fashion.
Your mileage may vary.
A word of caution: blue light isn't always good for you. Too much, especially in the absence of other light, can damage your eyes [3]. (Be especially careful if you have had cataract surgery.) At the wrong time of day, it will mess up your circadian rhythm (body clock) [4]. And if you have a tendency to migraine headaches, you might not want to use this light [5] at all. If in doubt, consult your doctor.