DIY 4 by 4 LED Matrix

Here’s a neat little DIY 4 by 4 matrix LED thingee…

A few years ago, when I finally got around to learning PIC programming, I decided to I wanted to create something that would run LED animations on a small 4×4 matrix. I liked the idea of the small 4×4 size because I was starting with a PIC 16F628A. This chip can not directly control the 16 lines necessary for an 8×8 matrix (unless you get fancy). Also the 4×4 arrangement just seemed easier to work with in terms of coming up with different patterns. And the patterns would require less memory. One frame on a 4×4 matrix is 16bits or just 2 bytes, but on an 8×8 matrix, a frame would require 8 bytes.

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