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Chapter 3 - AT Commands
$ Call Card Tone Detect
Use the $ command to dial services that require you to enter your call card number after a
tone. A $ character in the dialing string causes the modem to pause and wait for an AT&T
call card “bong” or a 1600 Hz tone (prevalent in the U.K.). When the modem detects the
tone, it processes the rest of the dialing string. If it does not detect a tone within the time set
by register S7 (a 45-second default), the modem aborts with a NO CARRIER message.
Pressing any key also aborts the $ command.
In the following example, the $ command is placed between an access/phone number and
the caller’s credit card number:
ATDT1028806127853500$123456789