The Saturn computer and data adapter, which were designed and manufactured by IBM's Electronics Systems Center in Owego, N.Y., were part of the launch vehicle's guidance system. They were located one over the other and were connected by wire harness in the instrument unit.
The computer handled the following functions:
Prelaunch Checkout: Using a self-contained program, it tested itself and the rest of the Saturn IVB launch vehicle's guidance and control system and its telemetry system. It also ran a mission simulation.
Booster Guidance: Processed data on velocity, position, altitude and time. Twenty-five times a second, it issued steering signals controlling the direction of thrust of the gimbaled rocket engines to keep the launch vehicle on course to orbit.
Saturn V Lunar Trajectory Injection: Issued signals to ignite the S-IVB engine and navigate the vehicle out of its earth orbit into a lunar trajectory. It calculated the Apollo's escape velocity and signaled engine cutoff. During the Apollo's turnaround and docking maneuver, it helped to keep the S-IVB stage stable.