Multicolor LED control through iPad audio (Jack) cable

Hi guys,

Working on a project here and I need some help, was hoping I could get it here :slight_smile:

I need an iPad (Mini 2 or Mini 3) to be able to control basic multicolor LEDs.
I'm thinking of buying a Neopixel ring (16 LED, NeoPixel Ring - 16 x 5050 RGB LED with Integrated Drivers : ID 1463 : $9.95 : Adafruit Industries, Unique & fun DIY electronics and kits) and a piece of NeoPixel strip.

I will be using an Arduino UNO. What I want is to be able to trigger any of these three cycles:

  • In 'standby mode', while the iPad is not used, the NeoPixels have to run through a basic color fading mode.
  • While the iPad is used, the NeoPixels have to stop at the curent color that was in the fade loop, and start to get the breathing effect (slowly going from lower to higher intensity light).
  • When the action performed on the iPad is done, I want the LEDs to blink maybe twice, in the same color as the previous action.

When this is done, it has to go in the standby mode again, the first cycle.

Without the iPad, this would of course work by for instance, pushing a button to go through these cycles. What I want, is to use the iPad headphone cable to trigger these cycles. The app that will be using this LED system could for instance produce a sound, only on the left channel. This would trigger cycle 2. And When there is a sound produced on the right audio channel, it should trigger cycle 3.

Do you think this would work? I've used these WiFi-controlled LED systems with the iPad but it is not stable enough for this purpose. That's why I want to make it out of an Arduino module. As said before, this system is running with a custom built app.

Thanks in advance!

So your first port of call is to make the arduino control the LED as you expect with a push button, once that is done, you need to learn how to read the presence of an audio signal on the headphone output,

then combine the two