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Appendix J - Internal MMH2834 Composite Link Modem Commands
RETURN. Do not include the letter D in this command, or the
stored number will be erased (also see Section J.1.3., on Phone
Number Memory Commands).
DTR
Dialing
$D
An alternate method of causing the MMH2834 to
automatically dial is DTR Dialing. Data Terminal Ready (DTR)
is a signal that comes into the modem from the
terminal or computer to which it is connected, on pin 20 of the
RS232C interface. In DTR dialing, the modem automatically
dials a stored number as soon as it receives a high DTR Signal.
The DTR dialing method is popular in synchronous applications.
To activate DTR Dialing, enter AT$D1 and hit RETURN. The
modem dials the phone number stored in the N0 location of
memory when it receives a high DTR signal. DTR must remain
high for the duration of the call, until disconnect. To deactivate
DTR dialing, enter AT$D0 and hit RETURN.
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