3Com 56K manual Register Default Function Bit Value Result

S-Registers I-5

Register	Default	Function
		Bit	Value	Result
		3	8	Disable 2100 Hz answer tone to allow
				two V.42 devices to connect more
				quickly.
		4	16	See next page.
		5	32	See next page.
		7	128	Unusual software incompatibility.
				Some software may not accept some
				result codes. This setting disables the
				codes and displays the 9600 code
				instead. The call's actual rate can be
				viewed on the ATI6 screen.
				Error control handshaking options:
				Select the total value of bits 4 and 5.
		0	0	Complete handshaking sequence:
				V.42 Detection, LAPM error control,
				MNP.
		16	0	Disable MNP.
		0	32	Disable V.42 Detection and LAPM.
		16	32	Disable Detection phase, if you know
				that the remote modem does LAPM,
				but not the Detection phase.
S28	8	Sets the duration in tenths of a second of the extra
		3000/600 Hz answer tones sent during V.32 hand-shaking.
		This gives V.32 modems additional time to connect in V.32
		mode before timing out.If there is difficulty answering
		older, manually operated V.32 modems (for example,
		modems that require a button to be pushed in order to dial,
		try lengthening the duration of the extra tones).Setting S28
		to zero eliminates the extra tones resulting in a faster
		connect time if, for example, the Business Modem is set to
		use V.21 modulation (300 bps) or V.23 modulation (1200
		bps).
S34	0	Bit-mapped register. See Chapter 1, Using the AT
		Command Set, for instructions about how to set
		bit-mapped registers.
		Bit	Value	Result
		0	1	Disable V.32bis. Used for
				troubleshooting; 3Com Technical
				Support may ask you to disable
				V.32bis for testing purposes.