IBM InfoPrint 6500, User Manual

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Serial matrix printers use a moving printhead with pins to form single characters
sequentially along the printed line. Unlike serial matrix printers, 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. The IBM 6500–v is a line
matrix printer.
During each sweep of the shuttle, 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, and the paper advances one dot row. The hammers print the
next row of dots as the shuttle sweeps in the opposite direction, as shown in
Figure 20, unless unidirectional printing is chosen.
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.
C2qu01
16
1 Hammer
Print Span
1 Hammer
Print Span
Start
Direction of shuttle movement
1
2
3
4
5
6
7
8
9
10
11
12
1
2
*
* *
*
* *
Used for lowercase descender only
Used for underline and lowercase descender
Space
Paper
Advances
Character
Line
Paper
Feed
Paper
Advances
Figure 20. Line Matrix Printing
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Infoprint 6500 User’s Manual