Westermo TD-22 - Manual (Page 27)

&Tn – Test and Diagnostics
The modem will perform selected test and diagnostic functions according to the parameter supplied.
A test can be run only when in an asynchronous operation in non-error-correction mode (normal or
direct mode). To terminate a test in progress, the escape sequence must be entered first, except for
parameters 7 and 8 (see Section 3.1.3). If S18 is non-zero, a test will terminate automatically after the
time specified by S18 and display the OK message.
&T0 Terminates test in progress. Clears S16.
&T1 Initiates local analogue loopback, V.54 Loop 3. Sets S16 bit 0. If a connection exists
when this command is issued, the modem hangs up. The CONNECT XXXX message
is displayed upon the start of the test.
&T2 Returns ERROR.
&T3 Initiates local digital loopback, V.54 Loop 2. Sets S16 bit 2. If no connection exists,
ERROR is returned. Sets S16 bit 4 when the test is in progress.
&T4 Enables digital loopback acknowledgement for remote request, i.e., an RDL request
from a remote modem is allowed. Sets S23 bit 0.
&T5 Disables digital loopback acknowledgement for remote request, i.e., an RDL request
from a remote modem is denied. Clears S23 bit 0. (Default.)
&T6 Requests a remote digital loopback (RDL), 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, due to the time setting according to
S18 has passed or due to the execution of the &T0 or H command, the modem will
report the number of errors occurred. S16 bit 6 will be set at the start of the test
sequence.
&T7 Initiates local analogue loopback, V.54 Loop 3, with self test as in &T6 above. If a
connection exists, the modem hangs up before the test is initiated. When the test is
terminated either via expiration of S18, or via the &T0 or H command, the number of
detected errors is reported to the DTE. Sets S16 bit 6 when the test is in progress.
Please also refer to S18
Vn – Result Code Form
This command selects the sending of short-form or long-form result codes to the DTE. The
parameter, if valid, is written to S14 bit 3.
V0 Enables short-form (terse) result codes. Line feed is not issued before a short-form
result code.
V1 Enables long-form (verbose) result codes. (Default.)
Please also refer to ATQn
28 6177-2203