Rockwell RCV144ACx, Command Reference Manual

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AT Command Reference Manual
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6.5 SERVICE CLASS 2 PARAMETERS
All Service Class 2 parameters can be read, written, and tested for range of legal values by the DCE. The general syntax is
described in Section 6.1.
Group 3 FAX devices negotiate session parameters in DIS, DCS, and DTC frames. The following parameters are provided to
condition the facsimile DCE for the capabilities it will offer and to report the session settings negotiated.
The three primary T.30 session parameters are +FDCC, +FDIS and +FDCS. They are compound parameters, using values
listed in Table 6-2 . Figure 6-1 illustrates their relationships.
Figure 6-1. T.30 Session Parameter Relationships
6.5.1 +FDCC, DCE Capabilities Parameters
Write syntax: +FDCC=VR,BR,WD,LN,DF,ED,BF,ST
Valid values: See Table 6-2
Default values: 0,3,0,2,0,0,0,0 (9600 bps fax models) or 0,5,0,2,0,0,0,0 (14400 bps fax models)
+FDCC allows the DTE to sense and constrain the capabilities of the facsimile DCE from the choices defined in CCITT T.30
Table 2. When +FDCC is modified by the DTE, the DCE FDCC into +FDIS.
6.5.2 +FDIS, Current Sessions Capabilities Parameters
Write syntax: +FDIS=VR,BR,WD,LN,DF,EC,BF,ST
Valid values: See Table 6-2
Default values: 0,3,0,2,0,0,0,0 (9600 bps fax models) or 0,5,0,2,0,0,0,0 (14400 bps fax models)
The +FDIS parameter allows the DTE to sense and constrain the capabilities used for the current session. The DCE uses
+FDIS to generate DIS or DTC messages directly, and uses +FDIS and received DIS messages to generate DCS
messages.
The DCE initializes the +FDIS parameter from the +FDCC parameter on initialization, when +FDCC is written, and at the end
of a session.