Cabletron Systems CSMIM-T1 manual DTR Control, Repeat Dial, Dn Serial-Port DSR/CTS Control, D0

	Commands
&Dn	DTR Control
&D0	Ignores DTR. DTR not needed for auto-answer.
&D1	Enters command state on detecting On-to-Off transition of DTR;
	DTR not needed for auto-answer.
&D2	Goes on hook on detecting On-to-Off transition of DTR and
	prepares the serial port to accept an AT at any speed. DTR needed
	for auto-answer.
&D3	Goes on hook and resets on detecting On-to-Off transition of DTR
	and prepares the serial port to accept an AT at any speed. DTR
	needed for auto-answer.
	The On-to-Off transition of DTR must last as long as the value
	specified in register S25 (default is 0.05 second). Positive
	transitions of DTR (Off-to-On) that occur within five seconds
	after disconnect are ignored.
-D	Repeat Dial
-D	<dial string> Where <dial string> is a string of up to 98
	characters. Valid dial string characters are: 0-9, dial modifiers,
	and for tone dial, #, A, B, C, D and *. The modem ignores invalid
	characters.
-DL	Redials the last number dialed.
	Redials a number up to 9 tries until connection. In reliable mode,
	it does not redial if a remote modem answers but fails to establish
	a reliable connection.
\Dn	Serial-Port DSR/CTS Control
\D0	DSR and CTS always On.
\D1	DSR and CTS follow DCD. If &C1 is also set, DSR follows off
	hook.
\D2	DSR and CTS both follow DCD.
\D3	DSR complies with ITU-T recommendations, CTS always On.
\D4	DSR and CTS comply with ITU-T recommendations.
	Controls the Data Set Ready (DSR) and Clear To Send (CTS)
	signals on the serial port.
	Table 7-1 shows the &C and \D settings and the result of
	combining the two commands:

CSMIM-T1 Hardware Installation Guide 7-11