Intel 537EX - Manual (Page 57)

536EX Chipset Developer’s Manual 57
Intel Confidential
Error Correction and Data Compression
The list of commands needed to enter a specific error correction or data compression mode are as
follows:
V.42 bis with fallback to MNP5, &F +ES=3,0,2 or +ES=3,0,2 “H3 %C1
MNP2–4 or V.42:
V.42 bis with fallback to V.42/MNP2–4: &F +ES=3,2,4 %C0 or +ES=3,2,4 %C0 “H3
-J1
V.42 bis only: &F +ES=3,2,4 -J0 or +ES=3,2,4 -J0 “H3
V.42 only: &F +ES=3,2,4 or +ES=3,2,4 -J0 “H0
-J0 “H0
MNP5 with fallback to MNP2–4: &F +ES=4,4,6 or +ES=4,4,6 %C1
MNP2–4 only: &F +ES=4,4,6 %C0 or +ES=4,4,6 %C0
Table 20. Resulting +ES Connection Types
+ES Settings (Answer Modem)
+ES Settings
(Originate Modem)
+ES=1, 0, 1
(Buffer)
+ES=4, 4, 6
(MNP Reliable)
+ES=3, 0, 2
(V.42 Auto-
reliable)
+ES=3, 2, 4
(V.42 Reliable)
+ES=1, 0, 1
(Buffer)
Buffer (normal) mode Modem hangs up Buffer (normal) mode Modem hangs up
+ES=4, 4, 6
(MNP Reliable)
Modem hangs up MNP 2–5 MNP 2–5 MNP 2–5
+ES=3, 0, 2
(V.42 Auto-reliable)
Buffer (normal) mode MNP 2–5 V.42/V.42 bis V.42/V.42 bis
+ES=3, 2, 4
(V.42 Reliable)
Modem hangs up MNP 2–5 V.42/V.42 bis V.42/V.42 bis
NOTES:
• MNP 5 requires the modem to be configured for %C1.
• V.42 bis requires the modem to be configured for “H3.
• Refer to \Cn and %An commands for more information about auto-reliable mode.
Table 21. V.44/V.42/V.42 bis and MNP Data Modem Command Descriptions
Command Default Description
%An 13
Set Auto-Reliable Fallback Character: In auto-reliable mode (+ES=3,0,2) with auto-reliable fallback
character enabled (\C2), receipt of the fallback character from the line during the V.42 detection phase
causes the modem to switch to buffer (normal) mode. This allows a remote user with a non-V.42 modem
to connect immediately with a V.42 modem. A space or carriage return is usually chosen for the fallback
character.
n = 0–127 (ASCII character)
%Cn 1
MNP 5 Data Compression Control: This command controls whether the data sent during the MNP
frames is compressed using MNP Class 5 compression standard. MNP 5 data compression can improve
throughput by as much as 150%.
Range: 0, 1
n = 0 No compression
n = 1* MNP Class 5 compression
NOTE: An asterisk (*) denotes the factory-default setting.