Patent ID: 8213821

Claim:
A method of synchronizing a plurality of coupled electrophotographic engines whereby engine 1 serves as a master and engine 2 serves as a slave, the method comprising: starting an engine 1 ; generating a timing mark in the engine 1 that indicates to an engine 2 that the engine 1 has started and communicating to engine 2 a timing mark indicating a position of a primary imaging member in engine 1 such that the timing mark allows the engine 2 to start at a slower speed than required for printing; generating a timing pulse by engine 1 and starting a timing counter upon receipt of the timing pulse from engine 1 ; generating a pulse from engine 2 and stopping the counter when the pulse from engine 2 is detected; calculating a delta time between the pulse from engine 2 and the timing pulse from engine 1 ; using a correction algorithm and the delta time calculated to calculate an actual speed for the primary imaging member in engine 2 that allows the engine 2 to be synchronized with engine 1 .