Instruction manual

239
6 Principles of Operation
Line Matrix Printing
The printer creates characters and graphics by printing patterns of ink dots an
entire line at a time. This technique is called line matrix printing.
Every text character is stored in printer memory as a pattern of dots on a
logical grid called the dot matrix. (See Figure 45.) The ink dots are made by a
row of small hammers mounted on a shuttle that sweeps rapidly back and
forth. Logic circuits divide every line of incoming data into horizontal dot rows.
The hammers put dots at the required positions for the entire
line by striking
an inked ribbon and the paper.
Figure 45. A Dot Matrix
112Column No.
0.01389 inch
0.02 inch
First row and column
of next character column
(at 10 cpi)
Lowest descender dot line
First row and column of next
character line (at 6 LPI)
0.00835 inch
0.10 inch