Printer for printing characters in two alternative print qualities

A printer prints characters by printing selected character elements in a matrix of print positions arranged in horizontal rows and vertical columns. The printer includes storage means for storing sets of character data elements which are used for printing the character elements. The printer also includes logic means for selectively performing logical operations on the sets of character data elements in order to vary the sets of character data elements in accordance with certain rules and thereby vary the print quality in the horizontal, vertical and diagonal directions of the characters which will be printed using the stored character data elements. The stored sets of character data elements are selected so that they can be used for printing characters which have a high print quality in the horizontal direction and a low print quality in the vertical and diagonal directions. In order to print characters in a low print quality the logic means derives subsets of the stored sets of character data elements and only these subsets of character data elements are used for printing characters. In order to print characters in a high print quality the logic means performs logical operations on the stored sets of character data elements so as to generate additional character data elements. These additional character data elements together with the stored character data elements are used for printing characters.