Multitech MultiModem MT5600ZDX User Manual page 33

4 AT Commands, S-Registers, and Result Codes
&Q5 Selects asynchronous operation with data buffering and error
correction. Same as N3.
&Q6 Selects asynchronous operation with data buffering and no
error correction. Same as N0.
Command: &S n Data Set Ready (DSR) Control
Values: n = 0 or 1
Default: 0
Description: &S0 Force DSR high (on) at all times.
&S1 Let DSR go high only during a connection.
Command: &T n V.54 Test Commands
Values: n = 0, 1, 3, 4, 5, 6, 7, or 8
Default: None
Description: The modem can perform selected test and diagnostic functions. A
test can be run only when the modem is operating in non-
error-correction mode (normal or direct mode). For tests 3, 6,
and 7, a connection between the two modems must first be
established. To terminate a test in progress, the escape
sequence (+++AT) must be entered first, except for parameters
7 and 8. If S18 is non-zero, a test terminates automatically after
the time specified by S18 and displays the OK message. See
also Appendix C.
&T0 Abort. Stop any test in progress.
&T1 Start local analog loopback, V.54 Loop 3. If a connection exists
when this command is issued, the modem hangs up. A
CONNECT message is displayed at the start of the test.
&T3 Start local digital loopback, V.54 Loop 2. If no connection exists,
ERROR is returned.
&T4 Enables acknowledgment for remote digital loopback request.
&T5 Ignores acknowledgment for remote digital loopback request.
&T6 Requests a remote digital loopback, V.54 Loop 2, without self-
test. If no connection exists, ERROR is returned. The
CONNECT XXXX message is displayed at the start of the test.
&T7 Requests a remote digital loopback, V.54 Loop 2, with self-test.
(In self-test, a test pattern is looped back and checked by the
modem.) If no connection exists, ERROR is returned. When the
test is terminated, the number of detected errors is reported to
the computer.
&T8 Starts local analog loopback, V.54 Loop 3, with self-test. If a
connection exists, the modem hangs up before the test begins.
When the test is terminated, the number of detected errors is
reported to the computer.
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