The dot matrix printing method allows a printer to easily form any desired character. It has a print head that contains 9 needles vertically and can create distinctive characters like with typewriter. In that sense it is one of the key features that the printer has. EPSON’s MX-80 Type II can control each needle programmably, expanding the ability of the printer.

See next how the print head works and forms a character.

(1) Dot Matrix Printer

The print head contains 9 “needles” or “wires” vertically. Each dot wire is

driven by an electromagnet which fires when told to

do so by the electronics

inside the

printer.

 

 

Signals from

the

computer cause the appropriate dot wires to be fired from

the

holder

and

to

impact carbon, causing the character

to be printed as a series

of

dots.

 

 

 

 

As an example (see Fig. 61). to print the letter “E", dot wires 1 through 7 are

fired first. They hit the ribbon. That makes marks on the paper. Then the head

shifts over a bit and dot wires 1, 4 and 7 are fired. In this manner, the character “E” is formed.

This is called “Dot Matrix Printing”.

Dots are printed according to a pre-designed “Matrix” or “Grid” system,

where each letter, number and

punctuation mark is formed

by arrangement

of dots. In the above figure, the

print head moves from left to right. Since the

MX-80 Type II is a bidirectional printing type, the head can

also move from

right to left to print characters.

 

 

NOTE: In the Text mode, a maximum of 7 dot wires are used for character formation.

See Appendix 4, Character Fonts.

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