Monome-like project- Connected to computer?

Hey guys,

Here's a description of the project I'm looking to build:

I want to make a men's jacket which has built into it 64 RGB LEDs and that are controlled by arduino. I intend to use SparkFun's 4x4 Button Pad Controller SPI, the 2x2 button pads, an Unsped Arduinome Shield, and an Arduino Duemilanove.

The jacket will have a 4x4 button pad on each side of the chest, and 4 of the 2x2 button pads running along each of the sleeves. - a total of 64 RGB LEDs.

Its going to be similar to an Arduinome, with the exception that it won't be used to control sound, and the input taken from the button pads will only control the light patterns and colours of the LEDs.

My questions:

  • Is it necessary to have the arduino connected to a computer in order to control the patterns of this many LEDs, or can I write a program and upload it to the Arduino to control the LEDs, without having it connected to a computer at all? (My hope is that I won't need to have the jacket connected to a computer haha).

  • What kind of power-supply options do you think I have here? Could I power this with 9 volt batteries, or possibly rechargeable batteries?

Thanks so much,


The Arduino doesn't have to be tied to the PC. You will only need it connected to the PC to upload the code. You can easily power this off of 9V batteries. Yes i said batteries. You'll want one to power the Arduino threw the Vin pin or power connector and another 1 or 2 to provide power to the LEDs. You'll probably need a few TLC5940 or similar I2C that will extend the number of available PWM pins on the Arduino.

possibly rechargeable batteries

I would go for rechargeable batteries.
64 RGB LEDs is 192 LEDs
At 20mA per LED you have a maximum current of 3.84 Amps.
That is a lot of current for a battery. If you are carrying it around you have a compromise between battery life and weight.

Good points, thanks for your responses!

Also, how can I calculate how long the battery will last given this number of LEDs? Is there a formula for determining battery life?