Total Control MP/16, Руководство оператора

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Modem Testing E-3
The modem responds OK. If the modem sends an ERROR
message, you have issued an invalid command.
5
If there were no errors, reset the modem to &M4, for error
control, unless you've issued the ATZ reset command.
NOTE:
If the modem is in online-command mode, that is, still
connected to a remote modem, and you send it an &T1 or &T8
command, it drops the call, enters AL mode, sends a CONNECT
result and waits for loopback characters.
&T8
This AL option causes the modem to send an internal test pattern
to its transmitter and loop it back to the receiver. An internal error
detector counts any errors and, when the test is ended, sends the
number of errors or 000 (no errors) to the screen.
Since you don't type anything during this test, and the modem
does not send anything to the screen, this option verifies only the
modem. If there are no errors but your problem continues, it may
be at the comput er interface.
1 The modem must be in Command mode. If you wish, set
Register S18 as a test timer, as explained earlier.
2 Send the modem the following command:
AT &M0 &T8 <ENTER>
The modem disables error control and enters AL mode. The
Modem LED glows green. The modem sends its internal test
pattern to the trans mitter, and loops the pattern back to the
receiver. You will not see any data on your screen.
3 End the test. If you set S18, the modem automati cally stops the
test at the timeout. If you didn't set Register S18, type AT&T0
to end the test. Or use ATH or the command that resets the
modem, ATZ. Both of the latter end the test and hang up the
modem.
The modem hangs up and returns a three-digit code, followed
by OK. A code of 000 indicates no errors were found. A code
of 255 indicates 255 or more errors. An ERROR message
indicates that you issued an invalid command.