Intermec Transaction Manager 9560, Руководство пользователя

Страница: 292 / 309

9560 Transaction Manager User’s Manual
G-14
Polling Mode D protocol
Communications protocol for connecting the reader to a 9160A or 9161A Port
Concentrator or a 9165B System Control Unit. Polling Mode D operates only at
2400 baud or higher and cannot be modified.
preamble
Predefined data that is automatically appended to the beginning of transmitted
data. When a preamble is enabled, you must enter a valid Preamble A or B
before the reader will send data to the computer. After exiting Prompting
Configuration, the reader will not accept data until a valid Preamble A or B has
been entered.
Program Acknowledgment character
See PAK.
PSS
Program Statement Separator character
Indicates the end of an IRL program statement and separates individual IRL
program statements from one another within a block of IRL program
statements. The PSS must be unique, and cannot be the same as EOM.
quiet zone
Area in a bar code immediately preceding the start character and following the
stop character that contains no markings and is free of any extraneous marks.
It is quiet in terms of the scanning signal produced.
reader
A device used for machine reading bar codes. Typically consists of a scanner, a
decoder, and a data communications interface.
read rate
Ratio of the number of successful reads on the first attempt to the number of
attempts.
regular label
Bar code label that takes the form of <start code data stop code>. Regular labels
are transmitted as soon as scanned.
REQ
Request for Acknowledgment character
Sent by the reader to the host to request a retransmission of an
acknowledgment to a reader message.