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cde

Motion Sensing Pantry Light

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A small project.

  • G2211
  • PIR Sensor
  • 5630 LED strips
  • On/Off button
  • Button Doubles as Test Mode

Board half way done. Using a Reg104 DPAK (I'll stick to a TO-220 next time) as the regulator, and MMBT3904 sot-23 transistors on a board of my own design. The base resistors should be on the back, but I didn't have the right value 0805/1206 resistors at the time.

post-44-0-60809100-1457829842_thumb.png post-44-0-20006900-1457829685_thumb.jpg

 

Quite proud of my clean, flush mount, perfect fit for the button, led, and sensor.

 

 

Two tricks. One, I used two pins to provide high to low, and low to high interrupts, instead of swapping the interrupt in code, since I won't always know it's state. It is much simpler like this for me. Two, the status led is only 0.66 mA. 600 microamps. Look how visible it is. Keep that in mind when building your own projects.

 

One issue. I have the PIR sensor directly powered by the 3.2V regulator I am using, bypassing the HT7133 on it. As such the PIR sensor triggers when the leds turn off, likely due to noise/ripple experienced. Next time I'll just power the sensor from the 12V with it's regulator, or I could change the sensor to non-retriggerable mode, or wire the enable pin to the msp430. I just coded a delay that ignores the trigger. The timing of the lights is long enough that it shouldn't be an issue in normal use.

main.c

common.h

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