3-2
Issue 1 April 1994
AT Command Guidelines
The following section lists guidelines for using AT commands.
G
AT commands must be entered while the DataPort 2001
is in either Command mode or (when the DataPort 2001
is
online with another modem) online Command mode.
Command mode is an idle state that allows you to
modify the DataPort 2001’s operating parameters or
issue DataPort 2001 commands.
G
The escape sequence (which consists of three
consecutive plus characters — +++) is used to enter
online Command mode from Data mode. (Data mode is
a state where all entries made from the computer are
considered data and are transmitted and received
between DataPort 2001s.
To return to Data mode from online Command mode,
use the ATO command.
G
All commands (except the A/ repeat command and the
+++ escape sequence) must begin with the characters
AT (attention) and end by pressing the Enter key.
TYPE:
AT commands are entered using the following
format:
TYPE:
AT
Xn
Where: X
is the AT command or S-Register and
n
is the
specific value for that command.
PRESS:
Enter
G
The AT (or at) prefix can be upper- or lowercase, but the
modem will not recognize mixed case prefixes (At or aT).
G
The data character format (how your data is structured)
for the AT command set must be one of the following. It
can be set using your communications software:
–
8 data bits + no 1 stop bit.
–
7 data bits + 1 stop bit (parity can be odd,
even, mark, or space).
G
Commands can be entered one at a time or in strings
(several commands at once). Strings can have up to
40 characters after the AT prefix. Spaces, parentheses,
and hyphens are not considered characters.