Paxar 9401 manual Communication Values Definitions

9401/9402 System Administrator's Guide

Communication Values - Definitions

Baud Rate

The baud rate is the speed, measured in bits per second, at which the printer sends or receives data. A commonly used baud rate for RS-232 communications is 2400 bits per second.

Word Length

Word Length specifies the number of bits the printer uses to define a character. The 9401 and 9402 printers accept a setting of 7 or 8 bit data, but do not use the high-order bit for data.

Stop Bits

A stop bit follows the data and parity bits to signal the end of a character.

Parity

Parity is a means of checking the validity of data entering the printer. The parity bit immediately follows the last data bit for a character. The computer adjusts the parity bit according to the parity so the data bits in the character, combined with the parity bit, form an odd or even number of high bits.

Data Flow Control

Data flow control is the means by which the printer tells the computer whether it is ready to accept data. DTR (Data Terminal Ready) flow control is most commonly used with an IBM-PC™ unless the PC has a special Xon-Xoff program.

In DTR mode, the printer activates DTR when it is ready to accept data from the host and deactivates DTR when its receive buffer is nearly full.

In Xon-Xoff mode, the printer sends the Xon character when it is ready to receive data and sends the Xoff character when its buffer is nearly full. The Xon character is 17. The Xoff character is 19.

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