Synxcom SM9234D, Руководство пользователя

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AT Commands
Page 42
When the modem transitions from the command state or online command state to
the online data state, the result code CONNECT should be issued at the bit rate
and parity used during the command state. When the modem transitions from the
online data state to the command state or online command state, the result codes
should be issued at the bit rate used during the online data state. Thereafter, any
unsolicited result codes should use the bit rate and parity of the last command line
issued by the DTE to the modem.
The characters of a response will be contiguous, with no more than 100
milliseconds of mark idle issued between characters in addition to stop elements.
Responses
There are two types of responses that may be issued by the modem: information
text and result codes.
Information Text. Information text responses consist of three parts: a header,
information text, and a trailer:
The characters transmitted for the header are determined by the V command.
The trailer consists of two characters, being the character having the ordinal value
of parameter S3 followed by the character having the ordinal value of parameter
S4.
Information text usually consists of a single line; information text returned in
response to some commands may contain multiple lines, and the text may therefore
include CR, LF, and other formatting characters to improve readability.
Result Code Parts. Result codes consist of three parts: a header, the result text,
and a trailer.
The characters transmitted for the header and trailer are determined by the V
command setting.
The result text may be transmitted as a number or as a string, also depending on a
the V command setting.
Result Code Types. There are three types of result codes: final, intermediate, and
unsolicited. Result codes are described in later in this appendix.
A final result code indicates the completion of a full modem action and a ability to
accept new commands from the DTE.
An intermediate result code is a report of the progress of an modem action. The
CONNECT result code is an intermediate result code. In the case of a dialing or answering