Abstract: A printer is shown which employs an improved data entry technique wherein a predetermined set up time is established for entering semi-fixed information, that is, information which changes but relatively infrequently. A bit map image of the semi-fixed information is created only once after the printer is initialized so that only a bit map image of variable information need be created each time the printer is operated to print. The printer further includes a limited keyboard for the generation of control signals to which the printer's processor responds differently depending upon the mode of operation of the printer. In one mode of operation, the printer's processor is responsive to the actuation of one key to control a display and the entry of data into a memory for printing. In a second mode of operation, however, the printer's processor is responsive to the actuation of that same key to control the movement of paper stock with respect to a print head.

Abstract: An ink jet printer is provided which will print in both the left to right and right to left directions of ink jet head travel with respect to the print media. Relative horizontal displacement of ink jet droplets caused by horizontal travel of the ink jet head is compensated for by a deflection plate system which is tilted with respect to the direction of travel to provide an electric field which tilts the pattern of ink jet droplets in an equal and opposite amount from that caused by horizontal movement of the ink jet head. In one direction of travel an ascending pattern of ink jet droplets is provided and in the other direction of travel a descending pattern of ink jet droplets is provided for printing so that the tilted deflection plate system compensates appropriately for the particular direction of travel.