A grain distributor including a timer coupled to a distribution spout that generates a series of particular time values. The control processor is programmed with an algorithm to pivot the distribution spout and to receive and record signals from the sensor as the sensor confronts each of the code clusters and each of the proof windows. The control processor is programmed with the algorithm to associate each signal from each code cluster with a particular time value generated by the timer and to memorize the particular time value associated with each code cluster in a long term memory and the control processor being programmed with the algorithm to associate each signal from each of the proof windows in a long term memory. The grain distributor is also self programming.