Chapter 7 – Result Codes
Multi-Tech Systems, Inc. AT Commands Reference Guide (S000273F) 46
Chapter 7 – Result Codes
The modem responds to commands from the DTE and to activity on the line by signaling to the DTE in the form of
result codes. The result codes that the modem can send are described below.
Two forms of each result code are available: long-form (verbose) response and a short-form (terse) response. The
long-form code is preceded and terminated by the sequence < CR> < LF>.
The short-form is terminated by < CR>, only with no preceding sequence.
If result messages are suppressed, nothing is returned to the DTE. The long-form results codes can be modified by
the OEM through the .INF file.
Terse
Verbose Description
+F4 +FCERROR High speed fax data (V.27, V.29, V.33, or V.17) is expected but a V.21 signal is received.
0 OK Command executed.
1 CONNECT Modem connected to the line. For X command values specifying no speed reporting, the
modem has connected to the line and either the line speed is 300 bps and line speed is
enabled, or the DTE speed is 300 bps and DTE speed reporting is enabled.
2 RING Ring signal detected. An incoming ring signal is detected on the line. What qualifies as a
ring signal is determined by country-dependent parameters.
3 NO CARRIER Carrier signal lost/not detected. Sent when trying to establish a call if:
1. Ringback is detected and later ceases but no carrier is detected within the period of
time determined by register S7, or
2. No ringback detected within the period of time determined by register S7. Also sent
when the modem auto-disconnects due to loss of carrier.
For X0, sent for the following conditions:
1. If busy tone detection is enforced, busy/circuit-busy has been detected.
2. If dial tone detection is enforced or selected, dial tone has not been detected.
4 ERROR Invalid command. Sent during an attempt to execute a command line if any of the
following conditions occur:
1. Command line contains a syntax error.
2. Modem cannot execute a command contained in the command line; i.e., the
command does not exist or is not supported.
3. Command parameter within command line is outside permitted range.
For X0, X1, X2, and X3, this message is sent instead of DELAYED and BLACKLISTED.
5 CONNECT 1200 Connected at 1200 bps. Modem connects to the line. Either the line speed is 1200
bps and DCE speed reporting is enabled, or DTE speed is 1200 bps and DTE speed
reporting is enabled.
6 NO DIAL TONE No dial tone detected. For X2 and X4, the modem has been instructed to wait for dial tone
during dialing but none is received.
7 BUSY Busy signal detected. For X3 and X4, if busy tone detection is enforced, the busy
(engaged) signal is detected on the line when the modem is attempting to originate a call.
8 NO ANSWER No answer at remote end. Modem is trying to originate a call if a continuous ringback
signal detected on line until the expiration of timer S7.
9 CONNECT 600 Connected at 600 bps; speed reporting enabled. Modem connects to the line, the DTE
speed is 600 bps, and speed reporting is enabled.
10 CONNECT 2400 Connected at 2400 bps; speed reporting enabled. Modem connects to the line; either the
line speed is 2400 bps with speed reporting enabled, or the DTE speed is 2400 bps and
the DTE speed reporting is enabled.
11 CONNECT 4800 Connected at 4800 bps and speed reporting enabled. Modem connects to the line; either
the line speed is 4800 bps with DCE speed reporting enabled, or the DTE speed is 4800
bps and the DTE speed reporting is enabled.
12 CONNECT 9600 Connected at 9600 bps and speed reporting enabled. Modem connects to the line; either
the line speed is 9600 bps with DCE speed reporting enabled, or the DTE speed is 9600
bps and the DTE speed reporting is enabled.