CHAPTER 6
SPECIAL FEATURES OF
THE PRINTER
Subjects covered in Chapter 6 include-
. Printer’s bell
•Master reset
•Uni-directional printing
•International character sets
•Printing BIG characters
•The optional sheet feeder
•Reading a hex dump
In the previous chapters we have learned about several groups of control codes. In this chapter we will look at more con- trol codes. These codes don’t fit neatly into any of the groupings that we have looked at so far, but they add a lot of useful features to your printer.
nNow hear this
You may have heard the printer’s bell if you have ever run out of paper. And you may have wondered why it’s called a bell when it beeps instead of ringing! It’s a long story that goes back to the early days of computers, when teletype machines were us- ed for computer terminals. These mechanical marvels were equipped with a bell that could be heard for blocks. This bell was used to signal the operator that something needed atten- tion. The code that the computer sent to the teletype machine to ring the bell was, reasonably enough, called a bell code. The name bell code is still with us, even if the bell has changed to a beeper, and a lot of people still call the beeper a bell, even if it doesn’t sound like one.
