Lpc2000

>  I think it might be difficult, given the I/O speed limitation.
>

That's true. Prior to the new high speed GPIO, most ARM chips could
only toggle at a speed under 4 Mhz. The new 2148 can toggle around 15
Mhz, but it's still going to be a challenge.

Might be wise to get one of the PIC-like devices from Ubicom to do
this kind of thing.

Eric