AUTO-RETRAIN - FALLBACK/FALLFORWARD
Type:	Configuration
Format:	AT [cmds] %En [cmds]
Example:	AT %E1 <CR>
Description:	Controls auto-retrain mode and fallback/fall forward.
Command	Function
» %E0	Auto-retrain disabled.
%E1	Auto-retrain enabled.
%E2	Fallback/fall forward enabled.

BIT-MAPPED REGISTER S14
Format		AT [cmds] S14? [cmds]
Example:		ATS14?<CR>
Default:		Read only
Range:		0-174
Unit:		Bit-mapped
Description:		Controls echo, result codes, result code display, dial mode, and answer/originate mode.
Bit	Value		Meaning
0	0		Not used.
1	0 » 1		Command echo disabled. Command echo enabled.
2	» 0 1		Result codes enabled. Result codes disabled.
3	0 » 1		Display result codes in numeric format. Display result codes in verbose format.
4	0		Not used.
5	» 0 1		Tone dial enabled. Pulse dial enabled.
6	0		Not used.
7	0 » 1		Answer mode enabled. Originate mode enabled.

BIT-MAPPED REGISTER S21
Format		AT [cmds] S21? [cmds]
Example:		ATS21?<CR>
Default:		Read only
Range:		0 - 124
Unit:		Bit-mapped
Description:		Selects CTS signal, low DTR action, DCD signal, DSR signal, and the Long Space Disconnect function.
Bit	Value		Meaning
1, 0	0		Not used.
2	0 » 1		CTS forced high. CTS follows RTS.
4, 3	00 01 » 10 11		DTR signal ignored. Modem goes to command mode on low DTR. Modem disconnects on low DTR. Auto-Answer is disabled. Modem is initialized on low DTR.
5	0 » 1		DCD forced high. DCD normal.
6	» 0 1		DSR forced high. DSR normal.
7	» 0 1		Long Space Disconnect function disabled. Long Space Disconnect function enabled.

BIT-MAPPED REGISTER S22
Format		AT [cmds] S22? [cmds]
Example:		ATS22?<CR>
Default:		Read only
Range:		0-127
Unit:		Bit-mapped
Description:		Controls speaker volume and controls, and limits results codes.
Bit	Value		Meaning
1, 0	00 » 01 10 11		Off volume. On volume. Medium level volume. High level volume.
3, 2	00 » 01 10 11		Speaker off. Speaker off on carrier. Speaker always on. Speaker on during handshake.
6, 5, 4	000 100 101 110 » 111		Basic result codes only enabled. Basic and connection speed result codes enabled. All results codes except dialtone detection enabled. Basic and connection speed result codes and dialtone detection enabled. All result codes enabled.

BIT-MAPPED REGISTER S23
Format		AT [cmds] S23? [cmds]
Example:		ATS23?<CR>
Default:		Read only
Range:		0-255
Unit:		Bit-mapped
Description:		Grants/denies remote digital loopback, controls DTE rate and parity, and sets guard tone.
Bit	Value		Meaning
0	0 » 1		Remote digital loopback denied. Remote digital loopback allowed.
3, 2, 1	000 001 010 » 011 100 101 110		Sets serial port speed to 0-300bps. Sets serial port speed to 600bps. Sets serial port speed to 1200bps. Sets serial port speed to 2400bps. Sets serial port speed to 4800bps. Sets serial port speed to 9600bps. Sets serial port speed to 19200bps.
5,4	00 01 10 » 11		Parity even. Not used. Parity odd. No Parity.
7, 6	» 00 01 10		Guard tone disabled. Guard tone disabled. Guard tone 1800Hz enabled.

BIT-MAPPED REGISTER S27
Format		AT [cmds] S27? [cmds]
Example:		AT S27?<CR>
Default:		Read only
Range:		0 - 127
Unit:		Bit-mapped
Description:		Selects async mode, and ITU-T/Bell modes.
Bit	Value		Meaning
3, 1, 0	00 » 01 10		Direct asynchronous mode. Reliable asynchronous mode. Normal Asynchronous mode.
5, 4, 2	0		Not used.
6	0 » 1		CCITT mode. Bell mode.

BIT-MAPPED REGISTER S28
Format		AT [cmds] S28? [cmds]
Example:		AT S28?<CR>
Default:		Read only
Range:		0 - 192
Unit:		Bit-mapped
Description:		Controls MNP10 link negotiation.
Bit	Value		Meaning
5 - 0	0		Not used.
7, 6	» 00 01 11		Link will be negotiated at highest possible speed. Link will be negotiated at 1200bps. Link will be negotiated at 4800bps.

BIT-MAPPED REGISTER S31
Format		AT [cmds] S31? [cmds]
Example:		ATS31?<CR>
Default:		Read only
Range:		0-15
Unit:		Bit-mapped
Description:		Controls auto-baud function and result codes.
Bit	Value		Meaning
0	0		Not used.
1	0 » 1		Auto-baud disabled. Auto-baud enabled.
3, 2	» 00 01 10		DTE speed displayed in result codes. Extended result codes enabled; DCE speed displayed in result codes. DCE speed displayed in result codes.
5 - 4	0		Not used.
7 - 6	» 11		Not used.

BIT-MAPPED REGISTER S40
Format		AT [cmds] S40? [cmds]
Example:		AT S40?<CR>
Default:		Read only
Range:		0 - 65
Unit:		Bit-mapped
Description:		Controls MNP10 data compression, power level adjustment, break type, and MNP block size.
Bit	Value		Meaning
1, 0	00 » 01 10		MNP10 disabled. MNP10 enabled. MNP10 enabled, except during V.42 answer detection.
2	» 0 1		Power level adjustment disabled. Power level adjustment enabled.
5 - 3	000 001 010 011 100 » 101		Displays \K0. Displays \K1. Displays \K2. Displays \K3. Displays \K4. Displays \K5.
6, 7	00 » 01 10 11		MNP block size is 64 characters. MNP block size is 128 characters. MNP block size is 192 characters. MNP block size is 256 characters.

BIT-MAPPED REGISTER S41
Format		AT [cmds] S41? [cmds]
Example:		ATS41?<CR>
Default:		Read only
Range:		0 - 255
Unit:		Bit-mapped
Description:		Selects compression, auto-retrain, flow control, and MNP mode.
Bit	Value		Meaning
1, 0	00 01 10 » 11		Data compression disabled. MNP5 enabled. V.42bis enabled. MNP5 and V.42bis enabled.
6, 2	» 00 01 10		Auto-retrain disabled. Auto-retrain enabled. Fallback/fall forward enabled.
3	» 0 1		Flow control disabled. Flow control enabled.
4	» 0 1		Stream mode for MNP. Block mode for MNP.
5	0		Not used.
7	0 » 1		MNP10 at 2400 and 1200bps disabled. MNP10 at 2400 and 1200bps enabled.

BREAK SEND
Type:	Configuration
Format:	AT [cmds] \Bn [cmds]
Example:	AT \B3 &W<CR>
Default:	3
Range:	1-9
Unit:	.1 second
Description:	Sends break to modem.

BREAK TYPE
Type:	Configuration
Format:	AT [cmds] \Kn [cmds]
Example:	AT \K1 <CR>
Description:	Configures action of break signal.
Command		Break from DTE	Modem receives \B	Break from remote modem
\K0		Enter command mode, do not send break to remote modem.	Buffers cleared and break sent to remote modem.	Buffers cleared and break sent to DTE.
\K1		Buffers cleared and break sent to remote modem.	Buffers cleared and break sent to remote modem.	Buffers cleared and break sent to DTE.
\K2		Enter command mode, do not send break to remote modem.	Send break to remote modem immediately.	Send break to DTE immediately.
\K3		Send break to remote modem immediately.	Send break to remote modem immediately.	Send break to DTE immediately.
\K4		Enter command mode, do not send break to remote modem.	Send break to remote modem with transmitted data.	Break sent with received data to the DTE.
» \K5		Send break with transmitted data.	Send break to remote modem with transmitted data.	Break sent with received data to the DTE.

CELLULAR TRANSMISSION LEVEL
Type:	Register
Format:	AT [cmds] @Mn [cmds]
Example:	AT @M26 &W<CR>
Default:	26
Range:	10-31
Unit:	-1dBm.
Description:	Sets the signal level for transmission when in leased line mode.
Command	Function
@M0	-26dBm.
@M1	-30dBm.
@M2-@M10	-10dBm.

CELLULAR TRANSMISSION LEVEL
Format			AT [cmds] S201=n [cmds]
Example:			AT S201=58 &W<CR>
Default:			58
Range:			0-255
Unit:			ASCII decimal
Description:			Sets the signal level for transmission when in leased line mode.
Bit	Value	Equiv.		Function
4 - 0	00000 ... » 11010 11111	@M0 ... @M26 ... @M31		Sets leased line transmit attenuation level to -26dBm. ... Sets leased line transmit attenuation level to -10dBm. ... Sets leased line transmit attenuation level to -31dBm.
5	» 0 1			Equalizer disabled. Equalizer enabled.

COMPRESSION
Type:	Configuration
Format:	AT %Cn
Example:	AT *EC0 %C1 *AP0<CR>
Description:	Selects data compression.
Command	Function
%C0	Data compression disabled.
%C1	MNP5 enabled.
%C2	V.42bis enabled.
» %C3	Both MNP5 and V.42 enabled.

COMPROMISE EQUALIZER
Type:	Configuration
Format:	AT [cmds] :En [cmds]
Example:	AT :E &W<CR>
Description:	Controls V.32 compromise equalizer.
Command	Function
:E0	Equalizer disabled.
» :E1	Equalizer enabled.

CONNECT MODE
Type:	Configuration
Format:	AT [cmds] \Nn [cmds]
Example:	AT \N1 DT555-1212<CR>
Description:	Sets connect mode.
Command	Function
\N0	Normal mode enabled.
\N2	Reliable mode enabled.
» \N3	Auto-reliable mode enabled.
\N4	LAPM mode enabled.
\N5	MNP mode enabled.

DTE SPEED OPTION
Type:	Configuration
Format:	AT [cmds] \Jn [cmds]
Example:	AT \J0 &W<CR>
Description:	Controls the speed of the DTE.
Command	Function
» \J0	DCE and DTE rates are independent.
\J1	DTE rate adjusts to DCE rate after connection.

FLASH DIAL MODIFIER TIME
Format	AT [cmds] S29=n [cmds]
Example:	ATS29=70<CR>
Default:	70
Range:	0-255
Unit:	.01 second
Description:	Time the modem will go on-hook upon receiving the ! dial modifier in dial string.

FLOW CONTROL
Type:	Configuration
Format:	AT [cmds] \Gn [cmds]
Example:	AT \G1 &K3<CR>
Description:	Selects modem port flow control.
Command	Function
» \G0	Flow control disabled.
\G1	Flow control enabled.

FLOW CONTROL CHARACTER - XOFF
Type:	Register
Format:	AT [cmds] S33=n [cmds]
Example:	ATS33=20<CR>
Default:	19
Range:	0-255
Unit:	ASCII
Description:	Sets the character used to represent XOFF.

FLOW CONTROL CHARACTER - XON
Type:	Register
Format:	AT [cmds] S32=n [cmds]
Example:	ATS32=20<CR>
Default:	17
Range:	0-255
Unit:	ASCII
Description:	Sets the character used to represent XON.

LINE SIGNAL LEVEL
Type:	Configuration
Format:	AT [cmds] %L [cmds]
Example:	AT %L &W<CR>
Description:	Returns recieved line signal level.

LINE SIGNAL QUALITY
Type:	Configuration
Format:	AT [cmds] %Q [cmds]
Example:	AT %Q<CR>
Description:	Displays line signal quality.

MAXIMUM BLOCK SIZE FOR TRANSMISSION
Type:	Configuration
Format:	AT [cmds] \An [cmds]
Example:	AT \A3 %C1<CR>
Description:	Sets the maximum transmittable block size.
Command	Function
\A0	MNP block size is 64 characters.
» \A1	MNP block size is 128 characters.
\A2	MNP block size is 192 characters.
\A3	MNP block size is 256 characters.

MNP STREAM/BLOCK MODE
Type:	Configuration
Format:	AT [cmds] \Ln [cmds]
Example:	AT \L1 DT555-1212<CR>
Description:	Selects the transfer mode for MNP.
Command	Function
» \L0	Stream mode for MNP enabled.
\L2	Block mode for MNP enabled.

MNP10 COMPRESSION
Type:	Configuration
Format:	AT [cmds] -Kn [cmds]
Example:	AT %C1 -K1 -Q0 <CR>
Description:	Selects MNP10 data compression.
Command	Function
-K0	MNP10 disabled.
» -K1	MNP10 enabled.
-K2	MNP10 enabled, except during V.42answer detection.

MNP10 FALL-BACK
Type:	Configuration
Format:	AT [cmds] -Qn [cmds]
Example:	AT *H0 -Q1 <CR>
Description:	Allows MNP10 to fall back to speeds slower than 4800bps.
Command	Function
-Q0	MNP10 at 2400 and 1200bps disabled.
» -Q1	MNP10 at 2400 and 1200bps enabled.

MNP10 LINK NEGOTIATION
Type:	Configuration
Format:	AT [cmds] *Hn [cmds]
Example:	AT *H0 -Q1 <CR>
Description:	Sets the speed at which MNP10 link negotiation will occur.
Command	Function
» *H0	Link will be negotiated at highest possible speed.
*H1	Link will be negotiated at 1200bps.
*H2	Link will be negotiated at 4800bps.

MNP10 POWER LEVEL ADJUST
Type:	Configuration
Format:	AT [cmds] )Mn [cmds]
Example:	AT )M1 %C1<CR>
Description:	Controls automatic transmit power level adjustment during MNP 10 link negotiation.
Command	Function
» )M0	Power level adjustment disabled.
)M1	Power level adjustment enabled.

PROTOCOL/SPEED
Type:	Configuration
Format:	AT [cmds] Fn [cmds]
Example:	AT F0 A<CR>
Description:	Selects the current protocol and speed.
Command	Function
» F0	Auto-select fastest common protocol.
F1	V.21/Bell 103A 300bps.
F3	V.23 1200/75bps.
F4	V.22/Bell 212A 1200bps.
F5	V.22bis.
F6	V.32bis/V.32 4800bps.
F7	V.32bis 7200bps.
F8	V.32 9600bps
F9	V.32bis 12Kbps
F10	V.32bis 14.4Kbps

REPORT INFORMATION
Type:	Immediate
Format:	AT [cmds] In [cmds]
Example:	AT I1 O<CR>
Description:	Displays modem properties.
Command	Function
I0	Reports product code.
I1	Reports ROM checksum result.
I2	Test ROM. Reports OK or Error.
I3	Reports ROM revision level.
I4	Reports modem identifier string.
I5	Reports country code.
I6	Reports data pump model.

SLEEP TIMER
Format	AT [cmds] S24=n [cmds]
Example:	ATS24=32<CR>
Default:	32
Range:	0 - 255
Unit:	1 second
Description:	Maximum duration of DTE and DCE inactivity allowed prior to initiating low-power sleep mode. S24=0 will disable timer.

TEST MODES
Format		AT [cmds] S16? [cmds]
Example:		ATS16?<CR>
Default:		Read only
Range:		0-125
Unit:		Bit-mapped
Description:		Controls loopback tests, analog, digital, remote digital, and self tests.
Bit	Value		Function
0	» 0 1		Local analog loopback not in progress. Local analog loopback in progress.
1	0		Not used.
2	» 0 1		Local digital loopback not in progress. Local digital loopback in progress.
3	» 0 1		Modem not in remote digital loopback. Remote digital loopback in progress.
4	» 0 1		Remote digital loopback not requested. Remote digital loopback requested.
5	» 0 1		Remote digital loopback w/ self-test not in progress. Remote digital loopback w/ self-test in progress.
6	» 0 1		Local analog loopback w/ self-test not in progress. Local analog loopback w/ self-test in progress.