I have seen a couple of videos and instructables where people have created a matrix of LEDs controlled by photodiodes/photoresistors inside coffee tables, so that when you put your hand over the table or put a mug down, the lights under the object light up.
I want to take this to the next level by controlling the matrix with a microcontroller. Reason being: I can do even more with the matrix, maybe turn it into a VU meter or do cool light shows.
Here is what I was thinking:
A 9x5 matrix of LEDs (blue) with a 8x4 matrix of sensors (photoresistors):
I have a couple of PIC microcontrollers with 36 I/O pins lying around plus some other smaller ones. I haven't used PIC MCs before so I thought this might be a good project to use them for.
Do you have any recommendations for the controller design? Maybe I could use 2 MCs, one for the LEDs and one for sensors? Maybe just use one MC and use demultiplexers to switch in the many sensors?
Lay it on me fellas!