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Chapter 4 - AT Commands, S-Registers and Result Codes
The MT2834ZPX responds with
“CONNECT”
on your video display
after the number is dialed and a connection signal is detected (since
the MT2834ZPX defaults to Enhanced V.34/V.42/V.42
bis
, the actual
response is "
CONNECT LAPM COMPRESSED
”). The modem is now
in
“On-Line”
mode, and is ready to communicate with a host site.
If no connection signal is detected within 45 seconds (this time period
can be adjusted by S-Register S7), the MT2834ZPX goes On Hook/
hangs up and returns to Command mode. At this point, your video
displays “
NO CARRIER
”.
Enter +++ATH<CR> to Hang Up On-Line (bring modem on-hook), and
terminate the modem's On-Line mode. At this point, your video
displays “
OK
”.
In addition to the call originating capabilities, the MT2834ZPX can also
automatically answer incoming calls. You need not be present. You
can, however, control the situation by configuring the modem to either
answer or not to answer, or to answer after a specified number of
rings. This is done by setting the value of S-Register S0 (modem
defaults to automatically answer an incoming call after one ring).
Modem AT Commands
AT commands are the means by which you, and your communications
software, are able to communicate with and configure your modem.
They enable you to establish, read, and modify parameters in addition
to dialing. The following provides a summary and brief explanation of
the AT commands recognized by the MT2834ZPX.
COMMAND: AT
VALUES: n/a
DEFAULT: n/a
DESCRIPTION:
Attention Code that precedes most command
strings except A/, A: and Escape Codes.
COMMAND: Return
VALUES: n/a
DEFAULT: n/a
DESCRIPTION:
Pressing RETURN key executes most commands.