Printronix

P9212, Setup Manual

Page: 18 / 206

1–8 Introduction
Protocols and Emulations
Protocols
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 the its host computer must use the same protocol.
Most impact printers use single ASCII character codes to print text, numbers,
and punctuation marks. Some characters, both singly and in groups of two or
more, 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 principal difference between most printer protocols is in the characters
used to create control codes and the ways in which these characters are
formatted.
You can select the protocol at the control panel. The printer stores three
protocols in ROM:
•
Printronix P-Series
•
Serial Matrix
•
P-Series XQ
Emulations
When the printer executes the character and control codes of another printer
protocol, we say that it emulates that printer. If the printer uses the P-Series
protocol, for example, it is emulating a Printronix P-Series printer.
As used in this manual, protocol and emulation mean the same thing. If the
printer is using the Serial Matrix printer protocol, for example, we can also
say it is in Serial Matrix emulation mode.
For additional information, refer to the Impact Printers Programmer’s
Reference Manual.