Abstract: A method and structure are provided which allow a print pass to be initiated even if a swath buffer in a multi-pass printer has not stored enough print data to utilize the full printhead. In one embodiment, if the swath buffer is full, a print pass is initiated using the existing print data in the swath buffer, which may result in using less than the full printhead. By allowing a print pass to start when the swath buffer is full, problems such as inconsistent, delayed, or interrupted printing are minimized or eliminated. In another embodiment, if a certain period of time has passed since a previous print pass, a print pass is initiated using existing print data in the swath buffer to print new rows and to print over previously printed partial rows to minimize hue shifts.

Abstract: Printhead longevity is extended by more uniformly utilizing individual printhead printing elements. A preferred algorithm moves an active zone of printing elements uniformly down the printhead on successive print passes. If insufficient printing elements are available to print the next pass, the active zone is moved to a point near the top of the printhead determined by a modulo function.