Printronix P5000LJ user manual Line Matrix Printing, Dot Matrix Character Formation

Chapter 1 Printer Overview

Line Matrix Printing

Your printer is an impact printer; it creates characters by printing ink dots on paper. The dots are printed on an invisible matrix mapped in printer memory (see Figure 2). Dot impressions are made by an array of steel hammers mounted on a rapidly oscillating shuttle. The hammers strike the paper through a moving ink ribbon.

Dot Column

Matrix visible only to the printer

Dot Row

Ink dots formed by hammer tips.

Character Row

Character Column

Figure 2. Dot Matrix Character Formation

Serial matrix printers use a moving printhead with pins to form single characters sequentially along the printed line. Unlike serial matrix printers, the P5000LJ printer is a line matrix printer. Line matrix printers divide every printable line into horizontal dot rows, then print a dot row of the entire line at every lateral sweep of the shuttle.

During each sweep, hammers are activated to print dots at the required positions in the dot row. When the shuttle reaches the end of a sweep, it reverses direction, the paper advances one dot row, and the hammers print the next row of dots as the shuttle sweeps in the opposite direction, as shown in Figure 3.

After a line of characters is printed, the paper advances to the first dot row of the next print line. This creates a number of blank rows between lines of characters, depending on the print mode and line spacing you selected.

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