COMSPHERE 3900 Series Modems
14-2
September 1998
3910-A2-GN32-40
Use the O command to return to Data mode from online Command mode. Enter the following
command:
TYPE:
ATO
PRESS:
Enter
Command Guidelines
Review the following guidelines before using any AT Commands.
•
The escape sequence ( + + + ) is used to enter online Command mode from Data mode.
•
The asynchronous character format for the AT command set must be one of the following:
— 8 data bits + no 1 stop bit.
— 7 data bits + no 2 stop bits.
— 7 data bits + 1 stop bit (parity can be odd, even, mark, or space).
•
All commands (except A/ and + + + ) must begin with the characters AT and end by
pressing the Enter key. The AT (or at) prefix clears the command buffer and matches the
modem speed and parity to that of the DTE. Commands can be upper- or lowercase, but the
modem will not recognize mixed case prefixes (At or aT).
•
Commands can be entered one at a time or in strings. Strings can have up to 40 characters
after the AT prefix. You can use spaces, hyphens ( - ), and parentheses ( ) as fillers to make
the commands easier to read; the modem ignores these fillers and they are not counted
among the characters which make up the command string. Commands must be entered on
one line and end with the carriage return character (Enter key).
•
Commands with the suffix n have several options associated with them. For example, in the
Ln command, L1 sets the speaker volume to Low and L3 sets the speaker volume to High. If
no value is entered for the n suffix, the modem assumes a zero ( 0 ) value.
•
The A/ command (without pressing the Enter key) causes the modem to repeat the last
command entered.
•
Valid commands are acknowledged with numeric or word result codes (unless the result
codes have been disabled using the Q1 command). Table 14-1 lists all available result codes
with numeric and word equivalents.