Neopixel Matrix with Tinket and ATTiny IR Receiver - How to Wire it all up

Projects General Guidance
1

Hi,

I recently purchased the Adafruit Neomatrix board, which has 64 super-bright RGB LED's that can be controlled via one pin (so cool!) and their Arduino Library. It works really well. When all the LED's are lit (at color white) they draw a total of 3.5A (at 5V).

To power the board, the company recommends an external power supply (e.g. 5V 2A wall wart). I'd like to hook the board up to an Adafruit Trinket (5V) which is a small Arduino board that they make.

I also want to use an IR receiver so I can turn the board on and off with a remote (the project will be in a glass cube, making the cube look like it's glowing). The problem with having the IR receiver (as confirmed by Adafruit support) is that the Neomatrix board uses all the interrupts, to the IR receiver won't work.

The idea I had was to add an ATTiny 85 to my project which will be hooked up to the IR Receiver, and the ATTiny would be used to trigger a relay or a transistor that would control power (or data?) going to the Neomatrix board.

So my questions are:

  1. Is my approach (separate ATTiny chip for the IR receiver) a solid approach for this?
  2. Can I wire the Neomatrix board, the Trinket, and the ATTiny all to the same (+) wire (on a breadboard) coming from the wall wart?
  3. Should I use a transistor or a relay?
  4. What should the relay control? The data line to the Neomatrix board or the power wire to the Neomatrix board?

Looking for some guidance!

Thanks!

2

For the IR part only:
Look at the IRLib library, which can operate with/without interrupts when receiving.

However, this could(?) cause a problem if you are trying to update the LEDs when an IR signal is being received.

PS: How are all the interrupt pins used up, if its only using one Pin? IRlib now allows receiving via any INTx pin.