I'm working on a CD audio player using a Netduino Mini as an ATAPI disk drive controller. ATAPI means ATA Packet Interface and is an extension of old ATA (IDE) which today is more known as PATA since the introduction of SATA (Serial ATA).
For this, I used my LCD IR controller from this post and three more PCF8574 I2C I/O-expander ICs. It took some struggling with the IDE register based protocol which requires no less than 24 digital IOs (hence the expanders) but luckily the internet is full of useful information.
This is just a first test and there's much more work to be done but the thing actually works and with the remote it can do, play/pause, next, eject, etc.
I think this is the first ever Netduino (mini) based CD player
Here's a picture, I'm sorry for the tiny size - I seem to be out of quota or something, I'm only allowed to upload 3kB now
EDIT: A good fairy just gave me some extra quota so here's a much better picture of the setup:
mini_cd_player.JPG 152.5KB 53 downloads
The thing to the left is the PSU made from an eBay DC/DC step down with a MOLEX plug on it to supply the necessary 12V and 5V (2A each since these old buggers are really power hungry). The smaller floppy connector is used to power the Netduino so that's why it's goes into the breadboard while the MOLEX sits on the back of the CD drive.
Here's a demo video where I connected the CD player to a small digital amplifier with analogue input: