Western Telematic APS-16M, APS-8M manual Data Terminal Ready DTR Control

		The Internal Modem
Command	Function/Options
&Dn	Data Terminal Ready (DTR) Control.
	&D0	Modem ignores true status of DTR signal and responds
		as if it is always on.
	&D1	If DTR drops while in online data mode, the modem
		enters command mode, issues an OK, and
		remains connected.
	* &D2	If DTR drops while in online data mode, the modem
		hangs up. If the signal is not present, the modem will
		not answer or dial.
	&D3	If DTR drops, the modem hangs up and resets as if an
		ATZ command had been issued.

En Set Modem Command Mode Echo.

E0 Disable echoing of command mode characters.

*E1 Enable echoing of command mode characters.

&Wn	Store Current Modem Configuration.
		&W0	Stores current modem settings in non-volatile memory
			and causes them to be loaded instead of the factory
			defaults at power-on or when the ATZ command
			is invoked.
	*	&W1	Clears user default settings from non-volatile memory
			and causes the factory defaults to be loaded at power-on
			or following the ATZ command.
+++AT	In-band Escape Sequence. Puts the modem in command mode
	(and optionally issues a command) while remaining online. Type
	+++AT and up to six optional command characters; then press
	[Enter]. Used mostly to issue the hangup command:
	+++ATT<CR>.
&Qn	Asynchronous Communications Mode.
		&Q0	Asynchronous with data buffering. Same as /N0.
	*	&Q5	Error control with data buffering. Same as /N3.
		&Q6	Asynchronous with data buffering. Same as /N0.
		&Q8	MNP error control mode. If MNP error control is not
			established, the modem falls back according to the
			setting in Register S36.
		&Q9	V.42 or MNP error control mode. If neither error
			control method is established, the modem falls back
			according to the setting in Register S36.

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