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4. AT Command Set and S-Registers
4-213830-A2-GB91-30 August 1998
Table 4-2
(15 of 23)
Model 3830 AT Commands
&T
n
Tests
&T0 Abort. Stops any test in progress.
&T1 Local Analog Loop.
&T2 Pattern. Transmits and receives a 511 Bit Error Rate Test (BERT).
*&T3 Local Digital Loopback test.
&T4 Enables Receive Remote Loopback Response configuration
option.
&T5 Disables Receive Remote Loopback Response configuration
option.
*&T6 Remote Digital Loopback test.
*&T7 Remote Digital Loopback with Pattern.
&T8 Local Loopback with Pattern.
&T9 Self-Test.
To start a test, set the S18 register to a desired test duration in seconds
(for example, 30 seconds), and then issue the &T command. Test results
display as the number of errors sent or received over the number of
blocks sent or received.
* The modem must be online and in Direct mode for this test to work
properly.