Printer

Abstract

A printer includes LED heads and head controllers. Each head controller transfers items of data to a corresponding head over a set of common buses. The LED head has a receiver activated by a corresponding head selecting signal. In one configuration, the common buses may include a selector bus over a data bus. Image data and a group of signals are alternately transferred over the data bus, the group of signals including a latch signal for latching the image data into a corresponding head and a strobe signal for driving a corresponding head in accordance with the image data. The selector signal allows the receiver to direct the image data and the group of signals into separate data paths. In another configuration, the control signals may further include an image clock and a control clock. The common buses may include an image clock bus, a control clock bus, and a data bus over which the image data and the group of signals are alternately transferred, the image data being attended by the image clock and the group of signals being attended by the control clock. In still another configuration, the image data may include a train of image data in which first image data and second image data appear alternately. One receiver receives the first image data on the rising edges of the image clock and another receiver receives the second image data on the falling edges.