Multitech MMH900 User Manual page 152

maintaining the pseudo On-line mode with the remote modem.
4. Type ATU3 from the local PC and hit ENTER. Once you receive an
OK message from your modem (if responses are enabled), the local
modem is placed in Digital Loopback mode.
5. Data is typed from the remote keyboard. For this test, typing multiple
upper case "U" characters is a good way to send an alternating test
pattern of ones and zeros. The data received by the local modem will
enter its analog receiver, be converted to digital data, be reconverted
into analog, and then looped through its transmitter back to the
remote modem. Your modem passes this test if the data entered
from the remote keyboard is the same as the data received on the
remote monitor.
6. When testing is complete, you may end the test by typing an Escape
Sequence (+++AT<CR> or <BREAK>AT<CR>) to bring your
modem into 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 AT0 and hit ENTER. If you wish to
terminate the call, type ATH and hit ENTER to hang up.
Appendix I - Testing Your MMH 2834
152