I'm currently working on a design for a set of outdoor, full colour, architectural lights.
The aim is to use three arrays of Power LEDs (one of Red, Green and Blue) behind a diffuser, and use PWM to alter the percieved colour. I plan to use MOSFETs to scale up the signal to power a number of LEDs as required.
The interesting part is I'd like to control them over Ethernet, possibly UDP, and use that medium to provide timing and settings.
First of all, I'm wondering what AVR might be most suited to providing 3 PWM channels as well as accepting input from an Ethernet device. Since size is going to be an issue (in the first instance I want to put this into some small halogen uplighters which are about 60mm diameter), perhaps a Tiny is the way to go, but I'm not entirely sure what capabilities I'm looking for. If hardware PWM is available, I'd like to use it - although I've implemented simple PWM in software before and know what it entails so I'm not ruling that option out either.
Also, there seem to be a number of Ethernet devices out there - like the Easy Ethernet AVR among others. I don't fancy reinventing the wheel, so if there is a boxed solution that'll deal with the gorey details of Ethernet communication (having studied Ethernet at degree level, I know first hand that it's a pain to deal with), then I'm willing to take it. I don't *really* need DHCP/BOOTP support.
I'd like to have full-duplex communication (so I could send status packets from each device, as well as device discovery).
If anyone has any advice on any of these points, I'd be most greatful to hear them! Thanks!