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ASD-4
• answer on one ring
• ignore dial tone
• originate
• return to “command state” or “command mode” upon disconnect
The dial string whose two variants are shown below will allow most modems to
use reverse modem protocol to send a call to your ASD-4’s MODEM or FAX
port. Callers should tell their modem to tone-dial one of these variants (they
should consult their modem’s manual as to which one, and they should
include the “ATDT” prefix only if they control their modem through line
commands rather than through software):
ATDT (phone number)R
or
ATDT (phone number)/R
When a calling modem receives this command, it goes off-hook, dials the
phone number, and then immediately begins transmitting a steady high-
pitched carrier signal. When the ASD-4 answers the call, it detects this carrier
signal from the calling modem and automatically routes the call to the
MODEM or FAX port without ringing the TAD and PHONE ports.
4.3 Using the Phone Company’s Distinctive Ring Service (DRS)
with the ASD-4
The phone company’s Distinctive Ring Service uses a single phone line for
multiple phone numbers and assigns a unique ring to each phone number.
Working in conjunction with this service, the ASD-4 identifies three distinct
ring types and individually directs calls to the corresponding ports:
Depending on what type of ring the ASD-4 detects, calls are routed to either
the TAD and PHONE ports, the FAX port, or the MODEM port. This means
that callers can dial different phone numbers to reach each of three types of
devices on your ASD-4 rather than using access codes or requiring you to
listen for specific ring patterns.
The ASD-4 recognizes ring types as different patterns of ring bursts. The
number (not the duration) of the bursts determines how the ASD-4 handles
call routing. The ASD-4 is factory-preset to recognize and automatically route
calls with these ring patterns:
Содержание ASD-4
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