by henryson » Thu Jul 04, 2013 7:04 am
Adding an fpga for routing would be fun, if only to have more fabric available, but a microcontroller might also do a fine job of routing signals for far less money. If we need to handle DSP signals (we should) then having the micro drive a physical mux would make the most sense, since that would prevent the signal bottleneck being the routing chip.
The propeller by parallax.com comes to mind as a fantastic and cheap option ($8 or so, plus whatever for the mux arrangement).
an 8-core chip, it allows you to run 8 different I/O programs simultaneously, in case the switching instructions need to come from the boards as well as to them.
A fancier option would be a cypress PSoC 5, although that option brings way more than you need, and costs more, the added features might be worthwhile in terms of what you can do with the routing. It has fpga and mixed signal capabilities inside. Their website seems to be having a fit at the moment, so good luck finding the data sheet.
I'd like to toss in some ESD protection to my wish list. Those boards aren't cheap, having another layer of zener protection and voltage stabilization (which wouldn't be hard to make an optional solder on to keep costs down) would likely be widely welcome.