5686G-PRO User Guide
Page
29
of
94
Copyright © 2018 USR, a Division of UNICOM Global
Testing the Courier Lite 56K Business Modem using AT&T
n
To perform local analog loopback and local digital loopback testing, use the AT&T
n
command. You
can type in your own data during testing or use the modem's internal test pattern and error detector.
See the following sections for more detailed information about each AT&T
n
command.
For your modem to
Command
End test
AT&T0
Local analog loopback
AT&T1
Local digital loopback
AT&T3
Local analog loopback with test pattern
AT&T8
Example:
Sending AT&T3 to your Courier Lite 56K Business Modem will allow a remote user to test
their connection to your modem.
Note:
Disable error control (using the &M0 command, refer to the Alphabetic Command Summary)
before testing. If the modem is detecting errors and retransmitting the affected data, your results
will be invalid.
Analog Loopback Testing
Local loopback testing checks the operation of the Courier Lite 56K Business Modem's transmitter
and receiver.
Using AT&T1
1.
Send
AT&M0&N3S14.0=0
to prepare the modem for testing.
This command disables error control, fixes the connection rate at 2400 bps, and makes the
modem return to command mode when you type +++.
