We found this document:
And it says "The number of possible inputs and outputs per PRU is fixed and each has 16 possible inputs and 15 possible outputs. Those are just the theoretical numbers - many inputs and outputs are not routed out to the P8 or P9 headers on the Beaglebone Black and the actual number of usable inputs and outputs is quite a bit lower."
So which BB is capable of most usable number of PRU channels? For our project we need 30 realtime inputs at 5MHz.
More questions will probably follow ;-)
Thanks!
Dom