MT3334HD8 User Guide
56 CommPlete Communications Server
2. Open your communications software and go into terminal mode. Type AT and press ENTER; you
should get an OK message. Type AT&E0<CR> to disable error correction.
3. Dial the remote modem and establish your online connection.
4. Type the escape sequence (+++AT<CR> or <BREAK>AT<CR>) to bring your modem into
command mode while maintaining the connection with the remote modem.
5. Type ATU2 and press ENTER. The local modem responds to this command by transmitting an
unscrambled marking signal, which causes the remote modem to place itself in digital loopback
mode. Then the local modem exits command mode and enters online mode.
6. Enter data from your keyboard. For this test, typing multiple uppercase
U characters is a good way
to send an alternating test pattern of binary ones and zeroes. Data received by the remote modem
enters its analog receiver, is converted to digital data, is reconverted into analog, and then is
transmitted back to your modem. Your modem passes this test if the data received on your monitor
is the same as the data entered from your keyboard.
7. To exit the test, enter an escape sequence (+++AT<CR> or <BREAK>AT<CR>), which returns
the modem to command mode. The modem should respond with an
OK
message. If you wish to stay
on line with the remote modem for normal data transmission, type ATO and press ENTER. If you
wish to terminate the call, type ATH and press ENTER to hang up.