Command Mode
While the AI1422E Reader is in Command Mode, the host computer sends commands to the AI1422E
Reader that can be used to control the operation and configuration of the reader. After the AI1422E Reader
receives a command, it transmits a command response message. Typically, the command message
contains
!Done,!Error,
or data relating specifically to the command request. These messages may be
of variable length since some commands require information as part of the message.
Communications can be lost if the host computer attempts to send certain commands under marginal
communications conditions. For example, if the host computer transmits the command request to change
the baud rate and the AI1422E Reader properly receives the request and transmits the
!Done
message,
one of the two following conditions may occur:
1. If the host computer receives the
!Done
message, then both the host and the AI1422E Reader
switch to the new baud rate, and communications are maintained.
Note: In many applications, the host must be set to the new baud rate as it will not change
automatically. The AI1422E Reader changes the baud rate immediately after issuing the
!Done
message.
2. If the host does not receive the
!Done
message transmitted by the AI1422E Reader, the host
assumes that the command was not properly sent and does not switch to the new baud rate,
causing a loss of communications.
CAUTION
The host computer should not attempt to change communications parameters or protocols
during marginal communications conditions; otherwise, a loss of communications can result.
Download Mode
In Download Mode, the AI1422E Reader allows the host to download new software.
While in Download Mode, the reader communications port parameters are fixed at the following factory-
default settings: 9800 baud, 8 data bits, 1 stop bit, no parity, software flow control (XON/XOFF), basic
protocol.
While in Download Mode, the AI1422E Reader turns RF off, does not process tags, and does not echo host
commands.
Command List
Reader commands are divided into groups based on primary function. The following sections provide
information about each command in command number order. Refer to
listings of commands in both numerical and alphabetical order.
In the Command Quick Reference list, the symbols < and > represent variable message data. These
symbols are not part of the message syntax. Hex digits (0–9, A–F) in either uppercase or lowercase
characters may be used in data strings and for hex digits A–F.
AI1422E Reader User Guide
TransCore Proprietary
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