complex LED programming

[reefhugger]

weve got a little something going that requires quite complicated light effects using microcontrollers and LEDs. do you know where to find more information on the circuitry of these intangible abstract gibbledy gobbly objects? do they make sense to YOU? do you know what materials i need? i will to divulge the purpose to private messages, but have to keep it secret from the masses. you want to help me, thats for sure!

[ibdave]

This guy might be able to help you.. His stuff is amazing

http://www.nw.com/nw/projects/brc/

[Zhust]

weve got a little something going that requires quite complicated light effects using microcontrollers and LEDs. do you know where to find more information on the circuitry of these intangible abstract gibbledy gobbly objects?

I happened to start using PIC microcontrollers from Microchip. Several other companies make similar products and they are all adequate -- you'll find proponents for any of them but you can really just pick one.

Microchip's 8-bit controllers are at this page but you may need to go through the home page and pick "8-bit PIC Microcontrollers". The chips are rather complicated (except to a computer engineer) but the documentation is very extensive. Each chip is basically a stand-alone computer with no operating system.

To program them you'll need a computer (a pretty vanilla PC will do; I augmented my Mac with one I had lying around) and a programmer.
Some places offer a cheap self-powered RS232 programmer and I had great luck with it at first but once it started giving me problems (i.e. not programming the chips correctly) it was a nightmare to figure out. Like a lot of other people, I spent the $85 on the Olimex PIC programmer I got from SparkFun here and never looked back. The Microchip assembler/linker/IDE is a free download, so the cost to get started is under $100.

The advantage of the PIC and other "professional" microcontrollers is that they are cheap even in small quantities. The 8-pin PIC12F683 is $2 or so in unit quantities and requires zero additional components -- it has an 8MHz internal clock, 1.5K programming space (which is bigger than you'd think), and 6 programmable I/O pins, 4 of which are A/D channels (one converter and an analog multiplexer). I also used the PIC18F252 which I guess they've upgraded to the PIC18F2520. That one has 28 pins with 24 I/O pins and costs $8 or so for the basic one. There are all sorts of configurations in-between.

The disadvantage is that they are programmed in assembly language which gives you complete control but, well, it gives you complete control.

So if you're looking for something simpler to program but maybe more expensive, then I hear the BASIC stamp from Parallax is the way to go. You write your software in BASIC, download it to the chip, and away you go. I haven't bothered with it because I figured all that money I spent on a Computer Science degree should be used somewhere.

Another good resource I mentioned before is SparkFun. They have a bunch of kits and parts to pretty completely build most projects. They also have a forum and some tutorials and such. I started there with their "blink.asm" program for getting started on PIC Microcontrollers: it makes and LED blink on one pin but it helps you figure out how to configure I/O pins and such.

Have fun!

[Ebenezer Squeezer]

Check this site out too. http://www.rgbled.org/