System Administration Guide
Chapter 4, Managing printers and print jobs

About serial communication parameters

About serial communication parameters

Each serial device is controlled by a series of communication characteristics that define the low-level communications with the printer. When you configure a new printer, the default values should be sufficient for most purposes.

The serial communication parameters are:

Baud Rate
Speed of the serial connection. The default speed is 9600bps; other choices are 300, 1200, 1800, 2400, 4800, 19200, and 38400.

Type of parity. The default parity is ``none''; other choices are ``odd'' and ``even''.

Flow Control
XON/XOFF flow control (handshaking) is enabled by default; other choices are ``none'' and ``hardware''. 

Flow control is used between the computer and the device to start and stop the flow of data when necessary (as when the device input buffer is full).

Character Size
Number of bits (7 or 8) per character. Character size is set to 8 bits by default (not to be confused with font size, which is the size of a printed character in points).

To change these parameters, see ``Changing printer names and connections''.

You can configure additional serial line characteristics using lpadmin(ADM) or by editing the print interface file (in the /usr/spool/lp/model directory) directly. See ``Creating printer interface scripts''.

The stty(C) manual page summarizes the various characteristics that can be set on a terminal or printer port; however, not all of the characteristics listed in stty(C) are important for printers.