Printer User Manual
Table Of Contents
- FRONT MATTER
- TABLE OF CONTENTS
- INTRODUCTION
- CHAP 1-SETTING UP THE PRINTER
- CHAP 2-PAPER HANDLING
- CHAP 3-USING THE PRINTER
- CHAP 4-USING SOFTWARE AND GRAPHICS
- Using the LQ-2550 With Application Programs
- Computer-Printer Communication
- Enhancing Your Printing
- Graphics
- User-Defined Characters
- Designing Your Characters
- Design Grids
- Data Numbers
- Sending Information to Your Printer
- Printing User-Defined Characters
- Copying ROM Characters to RAM
- Letter Quality Characters
- Proportional Mode Characters
- Superscripts and Subscripts
- The Graphics Command
- Column Reservation Numbers
- A simple Graphics Program
- Using Hand-Calculated Data to Print Graphics
- Using Software and Graphics
- Mixing Print Styles
- CHAP 5-MAINTENANCE AND TRANSPORTATION
- CHAP 6-TROUBLESHOOTING
- Troubleshooting
- Problems and Solutions
- The Printer Does Not Print
- The Printer Stops Printing
- The Printout is Spaced Incorrectly
- The Printout is Faint or Uneven
- The Printout is Not what You Expect
- Single Sheets Do Not Feed Properly
- Continuous Paper Does Not Feed Properly
- Cut Sheet Feeder Does Not Load Paper Correctly
- The Short Tear-Off Feature Does Not Work Properly
- Color Printing Is Not What You Expect
- Data Dump Mode
- CHAP 7-USING PRINTER OPTIONS
- CHAP 8-COMMAND SUMMARY
- APPENDIX A-TECHNICAL SPECIFICATIONS
- GLOSSARY
- INDEX

Because the dots overlap each other both horizontally and vertically
in the Letter Quality mode, it is difficult to see individual dots.
Instead, the letters and symbols seem to be made of unbroken lines.
In order for the dots to overlap vertically, the pins are in more than
one column, but the intelligence of the printer handles the timing of
pin firings so that the effect is of 24 pins arranged in a single vertical
column.
Dot patterns
Your printer’s print head is able to print graphics as well as text
because graphic images are formed on the printer about the same
way that pictures in newspapers and magazines are printed. If you
look closely at a newspaper photograph, you can see that it is made
up of many small dots. Your printer also forms its images with
patterns of dots, as many as 360 dot positions per inch horizontally
and 360 dots vertically. The images printed by the printer can,
therefore, be as finely detailed as the ones at the beginning of this
section.
Color graphics
With the color ribbon and appropriate software, you can print in a
wide variety of colors. Even if your software doesn’t support color,
printer command ESC r lets you select from seven basic colors,
including black. In addition, you can combine some of the basic
colors for a greater variety.
4-14 Using Software and Graphics