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6178-2203
&Tn – Test and Diagnostics
The modem will perform different tests and diagnostic functions according to the parameter supplied
with this command. Tests can only be run when the modem is in non-error corrective asynchronous
mode (normal or direct mode). To terminate a test in progress the escape sequence must be sent to the
modem first, except for test 7 and 8. If register S18 is non-zero the tests will terminate automatically
after the time specified in S18.
&T0
Terminates test in progress. Clears S16.
&T1
Initiates local analogue loopback, V.54 Loop 3. Sets S16 bit 0. If a connection with another
modem exists when the tests are started, this is disconnected. When the tests are started the
CONNECT xxxxx message will be displayed.
&T2
Returns ERROR.
&T3
Initiates local digital loopback, V.54 Loop 2. Sets S16 bit 2. If a connection exists when the
tests are started, ERROR will be reported to the terminal. When the tests are in progress S16
bit 4 is also set.
&T4
Enables another modem to request this modem for data loopback.
Sets S23 bit 0.
&T5
Disables a remote modem to request a digital data loopback.
Clears S23 bit 0. (Default)
&T6Request to a remote modem for a digital data loopback,V.54 Loop 2, with self test consisting
of a test pattern which is looped back and checked. If no connection with another modem
exists this command returns ERROR. When the tests are terminated, due to the time settings
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. The command sets S16 bit 5, upon start of the tests.
&T7
Initiates local analogue loopback, V.54 Loop 3, with self test as for &T6. If a connection
exists the modem hangs up before the test is initiated. When the tests are terminated, either
via expiration of register S18 or via commands, the number of detected errors is reported to
the terminal. When the tests are started S16 bit 6 is set.
&T8
Initiates a local loopback, V.54 Loop 3, with self test. (In self test a test pattern is looped back
and checked by the modem.) If a connection exists, the modem hangs up before the tests are
initiated. When the tests are terminated, either via expiration of S18 or via the &T0 or H
commands, the numbers of detected errors is reported to DTE. Sets S16 bit 6 when this test
is initiated. This command may not be available in all countries due to different regulations.
Please also refer to S18
Vn – Result Code Form
This command either returns result codes as a number or complete words.
The value is written to S14 bit 3.
V0
Returns a number as result code, line feed is not issued.
(Result codes, see page 35)
V1
Result codes are returned as complete words. (Default)
Please also refer to ATQn
