An Intro to arrays

Update: I added a video with my grad cap hacked with 64 individually addressed LEDs! This multiplexing/matrixing/array-ing sure is fun :3

This is pretty barebones so far. Be assured, more infomation will be added as I push along.

First I started with a really basic setup: 16 LEDs controlled by 16 pins. This is great, but leaves no pins left for output! Being limited makes me antsy, so I sat down and figured out how to get more.

Here is the code(first video):

main:

for b0 = 0 to 7
high b0
pause 250
low b0
next b0

for b0 = 0 to 7
high pinsc b0
pause 250
low pinsc b0
next b0

goto main

Controlling 16 separate motors/lights/etc. is great and all, but what if you want to do more?

I removed one 8 LED output bank and set up two of the free pins as "enablers". The 8 led pins are pulldown pins, and each enabler pin supplies a logic on/off to a 2N3904 Transistor to supply a +5 voltage.

A small change in code, and we are back in business! (second video)

main:

high pinsc 0
for b0 = 0 to 7
high b0
pause 250
low b0
next b0

low pinsc 0 high pinsc 1

for b0 = 0 to 7
high b0
pause 250
low b0
next b0
low pinsc 1

goto main

10 pins to control 16 LEDs? Cool!

This can be worked further. How many can we control with 16 pins?

With mathematics, all you have to do take the total number of pins you can use, divide by two, and then square that number.

With 16 pins: 16/2=8, 8^2=64! That's pretty sweet if you ask me.

This is just with one Picaxe 28x1 chip, what could we use to multiply the out pins with other chips to control a multitude more?