3Com Courier, Reference

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Testing the Courier V.Everything Modem using AT&T n 15-7
Testing Using
Keyboard Data
(AT&T6)
1 Send
AT&M0&N3S14.0=0
to prepare the Courier V.Everything modem for
testing.
This command disables error control, fixes the connection rate at 2400
bps, and makes the Courier V.Everything modem return to command
mode when you type the escape code (
+++
).
2 Establish a connection with the remote device
3 If you haven't already done so, arrange with the remote user t
cooperate with the test.
If necessary, set the remote device to acknowledge the remote digital
loopback request. For example, older modems need to be set to S16=8.
4 Send
AT&T6
to the modem. The modem enters remote digital loopback
mode, and, if the modem is an external model, the MR status light
flashes.
5 Type a short message. It will be looped back to your modem by the
remote device and to your screen for verification. (The remote user will
not see your data.)
6 Send the escape code,
+++
, and the
AT&T0
to end the test.
Alternatively, you can end the test by sendin
ATH
,
ATZ
, or
ATZ!
Be
careful, because ATZ and ATZ! reset the Courier V.Everything modem i
addition to ending the test.
If you issue an invalid command, the Courier V.Everything modem sends
an ERROR message. If you set Register S18, the Courier V.Everything
modem automatically ends the test when the test timeout is reached. See
the example in the previous section,
Stopping a Test for an example of
using S18.
Data errors indicate a problem with the remote device or with the phone
link.
7
Send
AT&M4
, unless you used a reset command (ATZ or ATZ!).