Abstract: A microprogrammed control apparatus for dot matrix serial printers and related printing method which allows increased horizontal resolution of the printing matrix and therefore the printing quality consistent with the restriction that no printing element can be actuated before a previous energization of any printing element has been completed. The increase of the horizontal resolution is obtained by using a character description matrix with high resolution and logic circuits responsive to binary configurations read out from such matrix. In a preferred alternative, the increase of the horizontal resolution is obtained by using a "compressed" character description matrix containing a plurality of printing patterns, one for each of the columns where printing has to be performed (hereinafter "column to be printed") and a corresponding plurality of codes, each related to a printing pattern and representative of the distance/time interval between the column to be printed and the previous column to be printed.

Abstract: A high quality printing method utilizing a matrix serial printer having a print head provided with needles arranged in a vertical column. The method comprises the steps of printing a print line in two print passes, and in advancing a platen, between the first and the second pass, by an amount equal to one and a half times the vertical pitch, center to center, between two contiguous needles.