3Com MSR 30, MSR 50 manual Specifies the communication standard to be adopted

494CHAPTER 29: MODEM CONFIGURATION COMMANDS

Table 80 Description on common AT commands

Command	Description
Bn	Specifies the communication standard to be adopted and the
	transmission speed. The communication standard can be ITU or Bell.
	The n argument can be 0, 1, 2/3, 15, or 16.
	B0 specifies ITU V.22 and sets the transmission speed to 1,200 bps.
	B1 specifies Bell 212 and sets the transmission speed to 1,200 bps,
	which is a default setting.
	B2/B3 disables ITU V23 return path.
	B15 specifies ITU V21 and sets the transmission speed to 3,000 bps.
	B16 specifies 103J and sets the transmission speed to 300 bps, which is
	a default setting.
En	Sets the modem to echo commands to the workstation. The n
	argument can be o or 1.
	E0 disables echo of commands to the workstation.
	E1 enables echo of commands to the workstation, which is a default
	setting.
Dn	Dial Command enables the modem to dial the number following D in
	the command line. In the mode of pulse dialing, the modem ignores
	nonnumeric characters.
Hn	Hang up Control specifies the way to hang up a modem,
	H0 hangs up a modem, which is a default setting.
	H1 disconnects a modem through off hook.
In	Inquiries to display the modem product ID, ROM checksum or ROM
	checksum status. The n argument can be 0/3, 1, 2, 4, 5 or 9.
	I0/I3 displays the default speed and hardware version of controller in
	the modem.
	I1 calculates and displays ROM checksum.
	I2 checks ROM, calculates and checks checksum, and displays the
	information of OK or ERROR.
	I4 displays hardware version of data pump.
	I5 displays the ID, software version, hardware version and the country
	code of modem board.
	I9 displays the country code.
Ln	Specifies the speaker volume to low, medium and high. The n
	argument ranges from 0 to 3.
	L0/L1 sets the volume to be low.
	L2 sets the volume to be medium.
	L3 sets the volume to be high.
Mn	Monitors a speaker to be on or off when faxing and communicating.
	The n argument ranges from 0 to 3.
	M0 sets a speaker to be off.
	M1 sets a speaker to be on before carrier signal is detected, M1 is a
	default setting.
	M2 sets a speaker to be on when modem is disconnected.
	M3 sets a speaker to be on before carrier signal is detected except the
	span of dialing.