Digital memory depth tillage system

摘要

A system is provided for monitoring and controlling the level of a working element of an agricultural implement including a digital comparator which compares stored digital signals with digital signals corresponding to the actual position of the working element. A secondary valve is controllable from the digital comparator to limit lowering movement. The actual position digital signals are developed by counters which count clock pulses during a pulse developed by a transducer circuit and having a duration corresponding to the vertical position of the working element. Such actual position digital signals are applied to latching circuits from which a signal may be applied upon operation of a memory reset button to memory latch circuits operative to provide the stored signals and such signals may also be applied to display latching circuits.