Abstract: Apparatus is disclosed for issuing commands for controlling the operation of a transport mechanism preferably of the type which transports a recording medium such as a magnetic tape for the purpose of stopping at a predetermined cue point location on the medium. The apparatus includes a counter which accumulates tachometer pulses that are generated by movement of the medium so that the instantaneous count of the counter always provides an indication of the distance from the cue point location. Division rate outputs of the tachometer rate are provided by the counter and means responsive to various predetermined counts selects one of the division rate outputs for application to an error detector which measures the period of the division rate signal and provides an overspeed indication when the period exceeds a predetermined value. The determination of an overspeed condition results in a deceleration command signal being generated.