Protocols And Emulations - Printronix H-SERIES P7000 User Manual

Chapter 1
Printer Overview

Protocols And Emulations

A protocol is a set of rules governing the exchange of information between the
printer and its host computer. These rules consist of codes that manipulate
and print data and allow for machine-to-machine communication. A printer
and its host computer must use the same protocol. As used in this manual,
protocol and emulation mean the same thing.
Most impact printers use single ASCII character codes to print text, numbers,
and punctuation marks. Some characters, are defined as control codes.
Control codes instruct the printer to perform specific functions, such as
underlining text, printing subscripts, setting page margins, etc. The main
difference between most printer protocols is in the characters used to create
control codes and the ways in which these characters are formatted.
When the printer executes the character and control codes of a particular
printer protocol, it is "emulating" that printer.
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