# Controlling multible leds

Hello!

This seems for me, like a difficult task, but maybe I am looking at the wrong ways to solve the problem.

I want a flat surface with multible lines of LEDs set up in groups of 9 in squares. I will try to fit between 30-50 groups on a certain space. (This is the final product, but i might just start with 5-6 groups)

Now, I want my phone to tell the first 9 LEDS, that LED number, 1-3-6 or something, should light up.

This will require alot of wiring, right? And the amount of pins on my Arduino will be few. I have read something about Charlieplexing, but the sites i have seen uses wiring.

Is it possible to create a curcuit or something similar to reduce the wiring? - and the space. I want it to be slim.

Any ideas?

Thank you

Flywall: Hello!

This seems for me, like a difficult task, but maybe I am looking at the wrong ways to solve the problem.

I want a flat surface with multible lines of LEDs set up in groups of 9 in squares. I will try to fit between 30-50 groups on a certain space. (This is the final product, but i might just start with 5-6 groups)

Now, I want my phone to tell the first 9 LEDS, that LED number, 1-3-6 or something, should light up.

This will require alot of wiring, right? And the amount of pins on my Arduino will be few. I have read something about Charlieplexing, but the sites i have seen uses wiring.

Is it possible to create a curcuit or something similar to reduce the wiring? - and the space. I want it to be slim.

Any ideas?

Surface mounting LEDs like those on your Arduino will keep it slim. If you want 50 groups, that's 450 LEDs! Not much chance of keeping that number in a small area.

Hey again

I'm thinking of an area of 2x3 inches, +-0,2 inches.

But is it possible to control each group, individual? When you push button1, LED 1,3,5 will light up untill next command. Pressing button2 will light up LED 1,2,4, and so forth.

I can make a prototype, with just a few groups like 4-6 groups.

You can also take those nice neopixel LED strips or Neopixel singel LEDs (check them here), only 3 Wires (VCC, GND, DataIN). They are addressable and there is a library available on adafruit. In fact, they are more expensive, but there are big advantages!

Dizeliun: when you say groups of 9 in squares. I'm not understanding how you can obtain a square with 9 LEDs since it would be uneven

3x3?