My obsession of LEDs has led me to this. Aurora 9×18 is a thing of beauty (if I can say so myself) – has 162 RGB-LEDs in a circular configuration. The color of each circle is controlled by a micro controller using a twisted form of PWM.
The micro controller (PIC24F08KA101) only has one PWM module, yet Aurora is capable of 27 (9xR,G,B) independent brightness control. This Instructable reveals the inner-working of Aurora 9×18 through the building process.Full Article Click here
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