Comtrol AT Command Set Rev A - Manual (Page 101)

AT Commands Reference Manual
100722B Conexant 3-75
<hd_auto> Specifies whether or not, in V.34 half-duplex operation,
additional procedures besides those specified in § 12/V.34
shall be performed by the modem when switching from
primary channel to secondary channel operation, and vice
versa. This subparameter should not be commanded.
<crc_type> Specifies the CRC polynomial used while operating in Framed
sub-Mode. The options are:
0 CRC generation and checking disabled (default).
1 In Framed sub-Mode, the 16-bit CRC is
generated by the modem in the transmit
direction, and checked by the modem in the
receive direction.
<nrzi_en> Specifies if Non Return to Zero Inverted (NRZI) encoding is
to be used by the modem for transmit and receive data. The
options are:
0 NZRI encoding and decoding disabled (default
and fixed).
<syn1>, <syn2> Specifies the octet value(s) to be used while performing
character-oriented framing. <syn1> is to be commanded to
255 (FFh); <syn2> is not to be commanded.
Reporting Selected Options
The modem reports the selected options in response to the following command:
+ESA?
The response is:
+ESA:
<trans_idle>,<framed_idle>,<framed_un_ov>,<hd_auto>,<crc
_type>,<nrzi_en>,<syn1>,<syn2>
Example:
+ESA?
+ESA: 0,0,0, ,0,0,255,
For the defaults.
Reporting Supported Options
The modem reports the supported options in response to the following command:
+ESA=?
The response is:
+ESA: (list of supported <trans_idle> values), (list of supported <framed_idle>
values),(list of supported <framed_un_ov> values), (list of supported <hd_auto>
values),(list of supported <crc_type> values), (list of supported <nrzi_en> values),
(list of supported <syn1> values), (list of supported <syn2> values)
Example:
+ESA=?
+ESA: (0),(0),(0-1), ,(0-1),(0),(255),