Fun with 8×8 LED Matrix
Posted in Arduino on Nov 7th, 2010
I’ve finally got around to wiring up my 8×8 LED Matrix and now it’s time for some fun with it. Though out playing with this I’ve learnt about shift registers and how we can use them along with a transistor array chip.
First things first, have a read and look through the Arduino’s ShiftOut guide as they are very well put together (keep re-reading it if it doesn’t make sense): http://www.arduino.cc/en/Tutorial/ShiftOut
To summarise the guide:
- A shift register allows you to have 8 outputs while only using 3 pins on the Arduino
- You send a byte to the shift register which has 8 bits (e.g. 10010000)
- You can combine shift registers so instead of having only 8 outputs you can have 16 when using 2, 24 when using 3, and so on
- When combining shift registers, instead of sending out the 8 bits to the first register and 8 to the second register it’s actually reversed, so the first 8 bits you send are actually for the second register and the next 8 bits go to the first register
