Multi-Tech Systems MT5600DSVD Data Carrier Detect DCD Control, Data Terminal Ready DTR Control

MultiModemDSVD User Guide			4 AT Commands, S-Registers, and Result Codes
Command:	&Cn		Data Carrier Detect (DCD) Control
Values:			n = 0 or 1
Default:		1
Description:	&C0		Forces the DCD circuit to always be high.
	&C1	DCD goes high when the remote modem’s carrier signal is de-
			tected, and goes low when the carrier signal is not detected.
Command:	&Dn		Data Terminal Ready (DTR) Control
Values:			n = 0, 1, 2, or 3
Default:		2
Description:			This command interprets the high to low transition of the DTR
			signal from the computer according to the supplied parameter.
			The action taken depends on the current &Q setting.
	&D0 &Q0, &Q5, &Q6: DTR is ignored (assumed high). Allows op-
			eration with computers that do not provide DTR.
	&D1 &Q0, &Q5, &Q6: DTR drop is interpreted by the modem as if
			the asynchronous escape sequence had been entered. The mo-
			dem returns to asynchronous command state without discon-
			necting.
	&D2 &Q0–&Q6: DTR drop causes the modem to hang up. Autoan-
			swer is inhibited.
	&D3 &Q0, &Q5, &Q6: DTR drop causes the modem to perform a
			soft reset as if the Z command were received. The &Y setting de-
			termines which profile is loaded.
			&Q5 or &Q6 and +FCLASS=1 or +FCLASS=2: Same as for &Q0.
			Note: If &D1, &D2, or &D3 is set, the modem will not dial
			without a DTR drop.
Command:	&En		V.42 Error Correction Modes
Values:			n = 0, 1, or 2
Default:		1
Description:	&E0		V.42 non-error correction mode (V.42 disabled).
	&E1	V.42 auto-reliable mode.
	&E2	V.42 reliable mode (V.42 enabled).
Command:	&En		Modem-Initiated Flow Control
Values:			n = 3, 4, or 5
Default:		4
Description:	&E3		Flow control disabled.
	&E4	CTS/RTS hardware flow control.
	&E5	XON/XOFF software flow control.

Note: See also the L5 and &K commands.

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