Giant Lite Brite Project: Help Needed

Thread Starter


Joined Apr 23, 2018
A group of classmates and I are trying design a giant lite brite board for displaying simple messages/images. The board will consist of 15 rows of 23 push buttons (345 push buttons in total). The idea is to enable a user to press various push buttons that individually change color each time a button is pressed. The approach we are taking is using microcontrollers to control multiple LEDs, rather than having a counter circuit controlling each push button. What we are struggling with is how to begin designing the circuits and understanding how to determine what our requirements will be for microcontrollers (i.e. number of inputs and outputs). Any suggestions are welcome.


Joined Jun 19, 2012
I would consider the PIC10F series micro-controllers.
$0.39 each in quantity- at the minimum, you might need 4 I/O's

Assuming you use an RGB light source:

1) switch
2) RED


Joined Mar 10, 2018
First the architecture. n x m multiplexed approach or addressable node
on a serial buss ? Like I2C, each node slave with its own address. Or a
combo of both, muxed (for switch scan) and addressable (for LED drive).

Or node like this - using
WS2812 adressable RGB driver. Scan the switches in a matrix and
output to serial buss address + control for the LED node corresponding
for the switch being pressed.

Regards, Dana.
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Joined Jun 19, 2012
Keep it simple.

Make a whole bunch of really simple little boards that don't talk to each other, or anything else.
Write the code that makes one work, then they all work, no surprises.
The wiring is simple, just run power to all of them.

As soon as you try to make some fancy addressable thing, the complexity and risk factors (like it doesn't work) go up exponentially.