Multiple LED control with microcontroller

Thread Starter

DancinNancy

Joined Oct 1, 2008
24
I need to wire up and control about 200 leds depending on a text file that i read in to a microcontroller somehow. I don't know how to do any of this but figured it wouldn't be the hardest thing to learn but everything i look up has so many different options for microcontrollers and programs to write code that i don't really know where to start. Could someone please point me in the right direction with a specific microcontroller that could handle this or how i should be going about this. Thanks
 

Thread Starter

DancinNancy

Joined Oct 1, 2008
24
It will be 6 columns with about 40 rows...it will have to read in a number for the column from a text file and the number for the row and light that specific led up
 

SgtWookie

Joined Jul 17, 2007
22,230
Do a Google search on "Charlieplexing" for a background.

As far as reading in a text file - that will be quite complex, but not so bad if the commands come from communications such as an RS-232 port.
 

mik3

Joined Feb 4, 2008
4,843
If charlieplexing seems complicated you can use a 5 to 32 decoder plus a 3 to 8 decoder combined to drive the 40 rows with just only 8 pins. Also, you will need another six pins to switch each column in sequence and determine which led will light each time my the row pins. If you make the switching fast then your eyes will see the leds as they are on all the time because of the phenomenon of the persistence of vision. If you want you can use another 3 to 8 decoder to drive your columns and save three more pins.

I did it with my spectrum analyzer here:

http://www.youtube.com/watch?v=j-4h3l9O4fc

I switch each column in sequence in a fast rate and control which leds on the column turn on ech time, thus i can control 100 leds with just only 20 pins of the microcontroller.
 
If charlieplexing seems complicated you can use a 5 to 32 decoder plus a 3 to 8 decoder combined to drive the 40 rows with just only 8 pins. Also, you will need another six pins to switch each column in sequence and determine which led will light each time my the row pins. If you make the switching fast then your eyes will see the leds as they are on all the time because of the phenomenon of the persistence of vision. If you want you can use another 3 to 8 decoder to drive your columns and save three more pins.

I did it with my spectrum analyzer here:

http://www.youtube.com/watch?v=j-4h3l9O4fc

I switch each column in sequence in a fast rate and control which leds on the column turn on ech time, thus i can control 100 leds with just only 20 pins of the microcontroller.
Sir,
I saw the video of your spectrum analyzer.
I am looking for project with the same idea.
i want 12*12 matrix of led similar to your spectrum analyzer.
but one thing i want to add with it.
i want each led control with the help of any remote control.
so i can on or off the led any of the led.
and the other thing is that if possible i want multicolor led instead of single color.
please help me with this i tried to search many things but i am not getting what i want.
please suggest me what controller i used which IC i preferred and what component i choose.

thank you.
 
Top