Intel confidential – Intel 537EX User Manual
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536EX Chipset Developer’s Manual
61
Intel Confidential
Error Correction and Data Compression
+DS44=m
3, 0, 0,
471,
942,
140,
140,
1884,
3768
V.44 Data Compression: This command controls the V.44 data compression function if provided in the
DCE. It accepts the following sub parameters:
m=[<direction>[,<compression_negotiation>[,<capability>[,<max_codewords_tx>[,<max_codewords_rx>
[,<max_string_tx>[,<max_string_rx>[,<max_history_tx>[,<max_history_rx>]]]]]]]]]
<direction> specifies the desired direction(s) of operation of the data compression function.
0
Negotiated… no compression
1
Transmit only
2
Receive only
3
Both directions, accept any direction
<compression_negotiation> specifies whether or not the DCE should continue to operate if the desired
result is not obtained.
0
Do not disconnect if Rec. V.44 is not negotiated by the remote DCE as specified in
<direction>. Always set to 0.
<capability> specifies the use of stream method, packet method, multi-packet method.
0
Stream method
1
Packet method
2
Multi-packet method
<max_codewords_tx> specifies the maximum number of codewords which should be negotiated in the
transmit direction.
256 to 65536
<max_codewords_rx> specifies the maximum number of codewords which should be negotiated in the
receive direction.
256 to 65536
<max_string_tx> specifies the maximum string length to be negotiated in the transmit direction.
32 to 255
<max_string_rx> specifies the maximum string length to be negotiated in the receive direction.
32 to 255
<max_history_tx> specifies the maximum size of the history buffer to be negotiated in the transmit
direction.
≥
512
<max_history_rx> specifies the maximum size of the history buffer to be negotiated in the receive
direction.
≥
512
+EFCS=m
0
32-bit Frame Check Sequence: Controls the use of 32-bit frame check sequence option in V.42.
0
Use 16-bit FCS
1
Use 32-bit FCS if available in remote DCE; otherwise use 16-bit FCS
2
Use 32-bit FCS if available in remote DCE; otherwise disconnect
Table 21. V.44/V.42/V.42 bis and MNP Data Modem Command Descriptions (Continued)
Command
Default
Description
NOTE: An asterisk (*) denotes the factory-default setting.