Last year my Wife and I started a new tradition of building a Gingerbread house for Christmas.
We had a few nicely decorated houses last year, and I wanted to do a little more this year.
Adding LEDs makes everything better, so that is exactly what I did!
This instructable will show you how to wire up a ginger bread house with many LEDs (41 in this case) while only using a few pins of a micro controller to control them all.
By using charlieplexing, we can have individually addressable LEDs without the need for shift registers or a micro with a lot of IO pins.
Step 1: LED Wiring
If you are like me and are making your own LED wires, this step is for you!
If you can take the advice from the next step, lucky you, you can skip the tedium!
Still with me?
You will need a fair amount of wire here, and it is very helpful if you can get pairs of wires that are connected.
I was given a big roll of ribbon cable, which made this task a lot easier.
After cutting a length of cable, I simply split it into groups of two wire.
So with wire and LEDs handy, lets get started.
Clip the leads of the LEDs so they are short, but still long enough to solder to.
Hold onto the clipped legs, they can be useful later on.
Put the clipped LED in a pair of helping hands to hold it still.
Strip the wires and put it in the other clip of the helping hand.
It helps to tin both the wire and LED legs before soldering them together.
Line up the wire with the LED and solder the wires to the legs.
It might be a good idea here to stick to a colour scheme if you can (red for anode, black for cathode), but I had a lot of different colours, so I didn't bother.
It is easy to determine which is which later, but you might make your life easier if you can do it.
For the other end of the wire, I originally left it bare (but tinned).
After using it like that, I realised I needed a better option.
As I connected all of the wires through a breadboard, I found it easiest to solder breakaway headers to the other end of the wire.
Just like the LEDs, tin both, use helping hands and solder them together.