Commodore MPS 1200 - Chapter 2 Printer Basics

Chapter 2
Printer Basics
In this chapter, we'll cover how to use the MPS 1200 printer with
commercial programs. We start with a discussion of how dot
matrix printers work and how they use PET ASCII/ ASCII codes to
communicate with computers. We then cover how to use the MPS
1200 with word processors, spreadsheets, and database programs.
DOT MATRIX PRINTING
The MPS 1200 is called a "dot matrix" printer because each charac-
ter is
printed as a group, or matrix, of dots. If you look very closely
at the
printed characters you can see the dots. Figure 2-1 shows
how the letter H is formed from 17 dots.
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Figure 2-1. The letter H is formed by 17 dots
To understand why a dot matrix printer prints as it does, we need
to look at the print head. The print head in the MPS 1200 consists
of a stack of9 pins placed one above the other as shown in Figure 2-2.
2-1