iPod + Arduino

hello iPod!

anaid — Thu, 02 Jul 2009 00:49:23 +0000

The iPod requires instructions to follow a specific order and to be in hexadecimal notation.

This instructions look something like this:

The structure in this sentence is very important. The first two bytes are the header. It always expects this header to start listening.

Then it expects the length of what is going to follow.

Next is a mode. There are 5 available modes:

byte mode

0×00 mode switching

0×01 voice recorder

0×02 simple remote

0×03 request mode status

0×04 advanced remote mode (AiR)

Next is a command. The command is the specific instruction in the mode. The list of commands will follow.

The next part is the parameter, some modes use the parameters and others don’t.

Finally there is a checksum that completes the byte structure. This is calculated with a formula:

int checkSum(int len, int mode, int command, int parameter(s)) {
int checksum = 0×100 – ((len + mode + command + parameter(s)) & 0xFF);
return checksum;
Serial.println (“checksum”);
}

Basic conections

anaid — Thu, 02 Jul 2009 00:27:30 +0000

The basic connection requires 4 pins:

1 and 11 go to ground.

12 is TX and it goes to RX on Arduino, which is digital pin 0 on the Decimila Board.

13 is RX and it goes to TX on Arduino, which is digital pin 1 on the Decimila board.

You can read the full pinout at pinouts.ru.

To start

anaid — Wed, 01 Jul 2009 23:44:38 +0000

To talk to the iPod through an Arduino you need a way to interface with it. This is where the iPod breakout board comes in. You can buy it from Sparkfun here. You can chose to solder wires straight into it or put some headers on it so you can change them around. If the breakout board seems too big for your final project you can use the iPod connector instead but I don’t recommend this for beginners to soldering since the pins are tiny.

You will also need an Arduino connected to your computer, a breadboard (optional), some wire and wirestrippers.

iPod code online

anaid — Tue, 30 Jun 2009 19:46:17 +0000

Adrian Game’s iPod Accessory Serial Protocol page and iPod Linux have great information on the commands and the structure used to send instructions to iPod. This is not Arduino specific.

Rosie Daniel’s blog has information on controlling the iPod remote with Arduino. This is great if you’re wanting to use the “basic” iPod functionalities, namely play/pause, next, previous, volume up, and volume down.

The instructions from the Arduino to the iPod are all going to happen in hexadecimal so you might want to familiarize yourself with the way it works. This translator often helped me put the instructions into perspective.