Intel 536EX manual Intel Confidential, Error Correction and Data Compression, +ES=1, 0, Notes

Error Correction and Data Compression

Table 20. Resulting +ES Connection Types

		+ES Settings (Answer Modem)
+ES Settings	+ES=1, 0, 1	+ES=4, 4, 6	+ES=3, 0, 2	+ES=3, 2, 4
			(V.42 Auto-
(Originate Modem)	(Buffer)	(MNP Reliable)		(V.42 Reliable)
			reliable)
+ES=1, 0, 1	Buffer (normal) mode	Modem hangs up	Buffer (normal) mode	Modem hangs up
(Buffer)
+ES=4, 4, 6	Modem hangs up	MNP 2–5	MNP 2–5	MNP 2–5
(MNP Reliable)
+ES=3, 0, 2	Buffer (normal) mode	MNP 2–5	V.42/V.42 bis	V.42/V.42 bis
(V.42 Auto-reliable)
+ES=3, 2, 4	Modem hangs up	MNP 2–5	V.42/V.42 bis	V.42/V.42 bis
(V.42 Reliable)
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.

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 21. V.44/V.42/V.42 bis and MNP Data Modem Command Descriptions

Command	Default		Description
		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
%An	13	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)
		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
%Cn	1	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.

536EX Chipset Developer’s Manual 57

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