Telenetics 56 - Manual (Page 42)

AT Commands
Page 34
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 command, the modem switches from command state to online data state, and
issues a CONNECT result code. This is an intermediate result code for the modem
because it cannot accept commands from the DTE while in online data state. When the
modem switches back to the command state it then issues a final result code (such as OK
or NO CARRIER).
Unsolicited result codes (such as RING) indicate the occurrence of an event not directly
associated with the issuance of a command from the DTE.