Like Airplay said, the Collins Pro Line II avionics in the Saab 340 are really quite "old school" by todays standards.
I remember working on them quite well. The autopilot would log faults in voliatile memory, meaning when power was removed from the aircraft, any logged faults were erased. Nothing like getting an autopilot gripe and bringing up the diagnostic page to find no faults recorded. And, of course, any intermittant problems were nearly impossible to track, since it always worked fine on the ground. Bad servo? Difficult to pinpoint until it suffered a hard failure.
Not to mention the AHC-85 attitude heading computers. A bastardized inbred between the older analog gyros and then newer laser ring gyros. Compass swings were always a two to three hour ordeal. I'm convinced the designers were either retarded or drunk when they came up with that design. Spinning drums with piezio electric tabs on them?!? What were they thinking? It was incredibly fragile. Set one in the back of your truck and allow it to fall over, and thet's all she wrote. Back to the shop for some $20,000 in repairs. I remember the box they came in--it was about five times bigger than the actual size of the computer, with specially cut foam packing.
The Pro Line II system is used on the EMB-120 as well as several other aircraft.