How to make a LED Scrolling Sign with multicolored LED"s

Oct 9, 1999
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So i graduate in 5 months or so. I want to go out in style. I was thinking of making an LED matrix mounted on teh cap. Made up of single LED's that are capable of producing multiple colors. I was thinking of changing colors and scrolling messages and graphics. Maybe even hooking it up to my Palm M100 for instructoins.

I can get a 9v 4300mha battery from work used for portable DVD players, its small enough and i can carry it on me to power the unit.

So who is goign to help me design this so i can build it. My knowledge in programmable controllers is extremely weak. I know i will need some sort of logic gate to control the scrolling message thinge. It shoudlnt be too hard to build would it?
 

Pulsar

Diamond Member
Mar 3, 2003
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I suggest you simply purchase one from the net.

Fully programming and building an LED + microcontroller is usually a task that take a college group 3 months, and thats with an instructor that fully knows the hardware walking them through it.

Connecting it your palm would be even more difficult.
 

JohnCU

Banned
Dec 9, 2000
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Originally posted by: LsDPulsar
I suggest you simply purchase one from the net.

Fully programming and building an LED + microcontroller is usually a task that take a college group 3 months, and thats with an instructor that fully knows the hardware walking them through it.

Connecting it your palm would be even more difficult.

indeed. i remember making my clock count from 1 to 8 using LEDs and man was it a bitch.
 

PottedMeat

Lifer
Apr 17, 2002
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Yeah, it's gonna take a while for you to figure out by yourself - maybe just buy one of those tacky scrolling LED belt buckles at the mall or something and modify it.

If you were to do it from scratch, you would have to figure out how many characters you want, the size of each matrix of characters, and multiple colors. I've never seen any RGB matrix LEDs ( the 5x7 variety ) and even if you do find them they'll probably be very expensive. This isn't even considering graphics. Off the top of my head if I did this maybe a high end PIC18 series MCU and a few 16 bit I/O expanders coupled into a custom PCB with an RGB LED matrix ( 16x32 or something i dunno ) and a serial EEPROM to store 'large' amounts of display data.
 

krotchy

Golden Member
Mar 29, 2006
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Another problem with hand built LCD controller/arrays, is that your going to end up taking up a large amound of physical space coming up with a working solution. On the other hand, manufactured things are done on a PCB which has been optimized based on their specs.
 

PottedMeat

Lifer
Apr 17, 2002
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Originally posted by: Jeff7

Multicolor array

Whoa that Multicolor array is pretty sweet - price is kinda what i figured it to be.

Does anyone have any idea how to drive that monster? I'm guessing you'd need 64x3 PWM drivers ( one for each of the LEDs ) to adjust the intensity - a D/A for each one would probably be too expensive. They should have integrated a serial/parallel driver for that thing.

I saw a LED sign at Sams Club a few weeks back up close - was probably $300 I think. It was configured kind of like that multicolor array but the LEDs looked shallower, used a clear lens, and was 7 pixels high x ~16 characters wide.
 

Jeff7

Lifer
Jan 4, 2001
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From the link:
"It's a monster to control, but just imagine what kind of colors you could produce by mixing!"

A starting point perhaps?

Or here


Google for LED array driver or LED matrix driver, or some variation of that, maybe look for schematics. If you're building from scratch though, this won't be an easy project, especially with that multi-color array.


Or just get this.
 

krotchy

Golden Member
Mar 29, 2006
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I dont know why I didnt think of Spark Fun. They are awesome for random DIY things. They are essentially a company consisting of a bunch of EE graduates from my school who decided to open an electronics shop. Note they will allow for direct pickup from Boulder, Colorado if you are in the state.