Again, not minicomputer, but the Burroughs B5000 did have "invalid address" detection, which would case the machine to switch from "normal" to "control" state with an interrupt. The problem with comparing the B5000 architecture to anything else is that it was quite liberally like nothing else.
Some may argue that the IBM S/360 had I/O protection, but those of us who played games with CCWs in user mode might take exception to that statement.:) One of the favorite CCW-writing exploits was to ring the 1052 console bell then execute a TIC (transfer in channel) back to the bell-ringing CCW. On one occasion that I'm aware of, this so panicked the operator that he pulled "emergency stop"... Ah, the good old days... --Chuck
