Friday, March 4, 2011

Although I like the scanning technique for the LEDs I was not as happy with their final brightness.  A friend at work suggested I slow the scan rate down a little.  I changed the interrupt from Clock/64 (from prescaler) to Clock/256 (to make it obvious).  Now I can see the scan rate but the brightness appears unaffected.

I am considering for V2 to employ 2 microcontrollers... $20 more but twice as bright.


  1. Are you sure it is the microcontroller causing the low output and not something in the code. I've seen a YouTube video that looks like only one microcontroller but a really bright output, even with more LEDs. Nice work.

  2. Jon - is it the one by sportly3? It might be the difference between using an LED driver board or not... I can only get 40mA from a digital pin and I only have 20 of them so the only way I have figured out so far is "scanning" through them which means they are only technically lit for 1/62nd of the time!