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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.
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.
Dot Column
Dot Row
Character Row
Character Column
Matrix visible only to
the printer
Ink dots formed by
hammer tips.