Patent attributes
A CPU and an image memory are provided in a printing apparatus. An interface circuit device for inputting/outputting signals representing image data is interposed between the CPU and the image memory. The interface circuit device constitutes of a plurality of SSTL circuits. One of two adjoining pixels in image data is changed into a non-inverted pixel, and the other is changed into an inverted pixel. In the SSTL circuits, to which inputted is a signal representing the one pixel, an input signal is inputted so as not to invert an input signal. In the SSTL circuits, to which inputted is a signal representing the other pixel as an inverted element, an input signal is inputted to the inverted element so as to invert an input signal. This suppresses an increase in cost and an increase in the size of a device, while reducing the current in impedance matching.