Intel manual Intel Confidential, Data Mode AT COMMANDS, 536EX Chipset Developer’s Manual

Data Mode AT COMMANDS

Table 18. Data Mode Command Descriptions (Continued)

Command Default Description

Synchronous Access Mode Configuration: controls the manner of operation of the Synchronous Access Mode in the DCE (if present).

Syntax:

+ESA=[<trans_idle>[,<framed_idle>[,<framed_un_ov>[,<hd_auto>[,<crc_type>[,<nrzi_en>[,<syn1>[,<sy n2>]]]]]]]]

<trans_idle> specifies the bit sequence transmitted by the DCE when a transmit data buffer underrun condition occurs, while operating in Transparent sub-Mode.

0In Transparent sub-Mode, DCE transmits 8-bit SYN sequence on idle. DCE receiver does not hunt for synchronization sequence

1In Transparent sub-Mode, DCE transmits 8-bit SYN sequence on idle. DCE receiver hunts for 8-bit SYN sequence

2In Transparent sub-Mode, DCE transmits 16-bit SYN sequence on idle. DCE receiver hunts for 16-bit SYN sequence

<framed_idle> specifies the bit sequence transmitted by the DCE when a transmit data buffer underrun condition occurs immediately after a flag, while operating in Framed sub-Mode.

0In Framed sub-Mode, DCE transmits HDLC flags on idle

1In Framed sub-Mode, DCE transmits marks (ones) on idle

<framed_un_ov> specifies the actions undertaken by the DCE when a transmit data buffer underrun or overrun condition occurs immediately after a non-flag octet, while operating in Framed sub?Mode.

0In Framed sub-Mode, DCE transmits abort on underrun in middle of frame

1In Framed sub-Mode, DCE transmits a flag on underrun in middle of frame, and notifies DTE of underrun or overrun

<hd_auto> specifies whether or not, in V.34 half duplex operation, additional procedures besides those 0, 0, 1, specified in clause 12/V.34 shall be performed by the DCE when switching from primary channel to

,0, 0, secondary channel operation, and vice versa.

0,	0	When switching between primary and secondary channel operation in V.34 half duplex, the
		DCE only executes those procedures defined in clause 12/V.34
	1	When switching between primary and secondary channel operation in V.34 half duplex, the
		DCE executes additional procedures as described in 8.8.5 besides those defined in clause
		12/V.34
	<crc_type> specifies the CRC polynomial used while operating in Framed sub-Mode.
	0	CRC generation and checking disabled
	1	In Framed sub-Mode, the 16-bit CRC specified in 8.1.1.6/V.42 is generated by the DCE in
		the transmit direction, and checked by the DCE in the receive direction
	2	In Framed sub-Mode, the 32-bit CRC specified in 8.1.1.6/V.42 is generated by the DCE in
		the transmit direction, and checked by the DCE in the receive direction
	<nrzi_en> specifies if Non Return to Zero Inverted (NRZI) encoding is to be used by the DCE for transmit
	and receive data.
	0	NRZI encoding and decoding disabled
	1	NRZI encoding enabled in the DCE in the transmit direction, and NRZI decoding enabled in
		the DCE in the receive direction
	<syn2> specifies the octet value(s) to be used while performing character-oriented framing.
	0–255	When <trans_idle>=0, specifies the 8-bit transmit idle sequence to be used by the DCE.
		When <trans_idle>=1, specifies the 8-bit synchronization sequence to be used by the DCE.
		When <trans_idle>=2, specifies first 8 bits of 16-bit synchronization sequence to be used
		by the DCE
	<syn1> specifies the octet value(s) to be used while performing character-oriented framing.
	0–255	When <trans_idle>=2, specifies last 8 bits of 16-bit synchronization sequence to be used
		by the DCE

NOTE: An asterisk (*) denotes the factory-default setting.

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