Facsimile mid-page restart

Abstract

The method and apparatus shown herein provide for restarting a facsimile operation after a mid-page interrupt without overlapping or splitting the image. Furthermore, this is accomplished in a facsimile system that does not have a one-to-one synchronous relationship between synchronized mechanisms in the system. In operation, a print carriage is synchronized to a false once-around signal related to the motion of a print drum. There is a predetermined cyclic relationship between the false once-around and the real once-around for the drum. If a mid-page interrupt occurs, the line position at the time of interrupt is remembered, and the particular relationship existing between the false once-around and the real once-around at the time of interrupt is remembered. The carriage is backed up to a point prior to the mid-page interrupt and rests until restart. Upon restart, the carriage is accelerated up to speed and resynchronized to the false once-around before it reaches the point of interrupt. The once-around to which the carriage is resynchronized has the same relationship to the real once-around as stored at the time of interrupt. When the carriage reaches the interrupt point, that position is detected, and the facsimile system resumes printing on the next line without splitting or overlapping the image.