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CHAPTER 4: Operation
NOTE
The comma (“,”) dial-string modifier causes most standard modems to
delay dialing for about two seconds, but some modems don’t recognize
the comma and some respond to it differently. If callers aren’t sure, they
should check their modem’s manual. (The ASD-4 needs a short delay for
processing between over-dialing attempts.)
NOTE
If you change the MODEM or FAX port’s access code to a number that
uses varying rather than repeating digits ([4][5][9][8] rather than [7][7],
for example), callers should use a similar dial string with pound signs
(“#”) as well as commas between retries of the access code. A local-call
example:
ATDT (phone number),4598,#4598,#4598
NOTE
If it turns out that your callers’ modems can’t handle dial strings as long
as the one in the previous note, there are several ways to keep the string
short. First, you might want to keep your MODEM or FAX port’s access
code down to two or three repeating digits. Second, callers might be able
to reduce over-dialing repetitions of the access code to three or even
fewer (several trial calls should establish how many repetitions are
necessary). Third, for long-distance calls, callers’ modems might support
a dial-string modifier that causes the modem to delay dialing for a longer
period, or to delay until a ring is detected. This character could replace
the first few commas after the phone number. Callers should check their
modem’s manual.
4.2.7.C Using Reverse Modem Detection
Before you read further: Not all modems are capable of operation in the
“reverse” mode. Consult your modem’s manual if you aren’t sure (or contact
the modem’s manufacturer if you can’t determine) whether or not your
modem has this capability.
To use the reverse modem protocol, both the sending modem (the calling
modem) and the receiving modem (the modem on the ASD-4’s MODEM or
FAX port) must be in the “reverse” mode. The ASD-4 must be programmed
so that its Reverse Modem Detection feature is turned ON, and the Reverse
Modem Port Selection is set to either the MODEM or FAX port (whichever
one your modem is on); see
Sections 5.3.8
and
5.3.12
.
The modem connected to the ASD-4’s MODEM or FAX port should be set
this way (refer to your modem’s manual for how to do this):
Содержание ASD-4
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