USRobotics V.34 user manual S51 Bit-mapped register. See instructions For S13

COURIER HIGH SPEED MODEMS

Register	Default	Function
S51	0	Bit-mapped register. See instructions
		for S13.
		Bit	Value	Result
		0	1	Disable MNP/V.42 for
				V.22 (1200 bps)
		1	2	Disable MNP/V.42 for
				V.22 bis (2400 bps)
		2	4	Disable MNP/V.42 for
				V.32/V.32 bis/V.32 terbo
				(9600/14,400/19,200/
				21,600 bps).
		3−6	_	Reserved
		7	128	Custom Applications.
				Handset Exclusion Delay.
				If the telephone and
				modem share the same
				line, and DTR is raised,
				the modem takes control
				of the phone line and
				disconnects the voice call.
				The modem stays on hook
				for the duration specified
				in S6 before it becomes a
				data call.
				Since there is no way to
				detect if the telephone is in
				use, the S6 delay occurs
				even if the telephone is not
				in use.
				The phone is re-enabled
				once the modem returns
				on hook.
S52	Reserved.

B-26 Summaries and Tables