Star Micronics SB-15 user manual Printing with DOT Graphics

CHAPTER 10

PRINTING WITH

DOT GRAPHICS

Subjects covered in this chapter include:

•SD-10/15’s bit image graphics capabilities

•Printing a pre-defined shape

•Plotting a calculated shape

•High resolution graphics

In Chapter 9 you were introduced to a form of computer graphics; you were able to actually define characters dot by dot. In this chapter you’ll learn to use the same principles to make SD- 1O/15 print whole pages of dot graphics! We’ll show you how to use dot graphics to create “super download characters.” In addition, you’ll see how your SD-lo/l5 printer can be used as a graphic plotter. This can have some practical business appli- cations as well as create some terrific computer art!

COMPARING DOT GRAPHICS WITH DOWNLOAD CHARACTERS

A good understanding of dot graphics requires an under- standing of how dot matrix printers work; you may want to review the first few pages of Chapter 9. The principles for dot graphics are the same as those for download characters.

There are some differences in the way they are implemented however. While download commands can be used to define a character between four and eleven columns of dots wide, dot graphics commands can be used to define a shape as narrow as one column of dots wide or as wide as 3264 dots on an SD-15! There is no “descender data” with dot graphics; graphics images are always printed with the same seven or eight pins of the print head, depending on whether you have a 7-bit or 8-bit interface