CONNECTIONS
Purpose	Location	Purpose	Location
Switched line	CN1	Power switch	SW1
Leased line	CN2	Scroll left	CN6
RS-232/422	CN3	Scroll right	CN7
DC power	CN4	Go up one level	CN8
Network Management (proprietary)	CN5	Go to top level	CN9

DIAGNOSTIC LED(S)
LED	Color	Status	Condition
PWR	Green	On	Power is on
PWR	Green	Off	Power is off
ALRM	Red	Blinking	Major alarm detected in a remote 391x series modem
ALRM	Red	Off	Normal operation
DIAG	Green	On	Modem is receiving diagnostic messages
DIAG	Green	Off	Modem is not receiving diagnostic messages
DTR/108	Green	On	DTR signal is high
DTR/108	Green	Off	DTR signal is low
RTS/105	Green	On	RTS signal is high
RTS/105	Green	Off	RTS signal is low
CTS/106	Green	On	CTS signal is high
CTS/106	Green	Off	CTS signal is low
TXD/103	Green	On	Modem is receiving data from DTE
TXD/103	Green	Off	Modem is not receiving data from DTE
LSD/109	Green	On	Carrier signal detected
LSD/109	Green	Off	Carrier signal not detected
RXD/104	Green	On	Modem is transmitting data to DTE
RXD/104	Green	Off	Modem is not transmitting data to DTE
SQ	Yellow	Blinking	Line signal is degraded or data path is being blocked
SQ	Yellow	Off	Normal operation
TEST/142	Yellow	On	Test connection established
TEST/142	Yellow	Blinking	Modem is upgrading firmware
TEST/142	Yellow	Off	No test connection established
RATE	Yellow	On	Modem is connected at less than configured speed
RATE	Yellow	Off	Modem is connected at configured speed
DIAL	Yellow	On	Modem is establishing a switched line connection
DIAL	Yellow	Blinking	Switched line connection established
DIAL	Yellow	Off	No switched line connection

ANTISTREAMING
Type:	Register
Format:	AT [cmds] S72=n [cmds]
Example:	AT S72=0 &W<CR>
Description:	Selects antistreaming option
Command	Function
» S72=0	Disabled
S72=1	10 seconds
S72=2	30 seconds
S72=3	1 minute
S72=4	2 minutes
S72=5	3 minutes
S72=6	5 minutes

AT COMMAND RESPONSE
Type:	Register
Format:	AT [cmds] S84=n [cmds]
Example:	AT S84=0 &W<CR>
Description:	Sets the response to AT commands.
Command	Function
» S84=0	Normal operation
S84=1	Execute valid commands, suppress error codes.
S84=2	Ignore configuration commands, always return OK error code.

AUTO BAUD
Type:	Register
Format:	AT [cmds] S78=n [cmds]
Example:	AT S78=0 &W<CR>
Description:	Allows modem to connect at remote modem’s modulation.
Command	Function
» S78=0	Auto baud enabled.
S78=1	Auto baud disabled.

AUTO-RELIABLE FALLBACK CHARACTER
Type:	Configuration
Format:	AT [cmds] %An [cmds]
Example:	AT%A20<CR>
Default:	19
Range:	0-127
Unit:	ASCII
Description:	Sets the character used as the auto-reliable fallback character. %A0 will disable this function.

AUTO-RELIABLE TIME BUFFER CONFIGURATION
Type:	Configuration
Format:	AT [cmds] \Cn [cmds]
Example:	AT \C1 &W<CR>
Description:	Controls the handling of incoming data during auto-reliable time period.
Command	Function
» \CO	Data is discarded.
\C1	Data is buffered.
\C2	Data is discarded, resets to \C1 on receipt of autoreliable fallback character.

BREAK TYPE
Type:	Configuration
Format:	AT [cmds] \Kn [cmds]
Example:	AT \K5 &W<CR>
Description:	Selects response to DTE break command.
Command	Function
\K0	Send break, clear buffer, enter command mode.
\K1	Send break, clear buffer
\K2	Send break, send data, enter command mode.
\K3	Send break. send data,
\K4	Send data, send break, enter command mode.
» \K5	Send data, send break.

BUFFER REDUCED ASYNCRONOUS
Type:	Register
Format:	AT [cmds] S97=n [cmds]
Example:	AT S97=0 &W<CR>
Description:	Limits asynchronous buffer size to a 20 character maximum
Command	Function
» S97=0	Buffer size limit disabled.
S97=1	Buffer size limit enabled

BUSY OUT ON LOW DTR
Type:	Register
Format:	AT [cmds] S69=n [cmds]
Example:	AT S69=0 &W<CR>
Description:	Modem goes off hook on low DTR (use only in PBX mode).
Command	Function
» S69=0	Busy out disabled.
S69=1	Busy out enabled.

CALLBACK SECURITY
Type:	Register
Format:	AT [cmds] S67=n [cmds]
Example:	AT S67=0 &W<CR>
Description:	Enables callback security option
Command	Function
» S67=0	Disabled
S67=1	Enabled

CD SIGNAL
Type:	Configuration
Format:	AT [cmds] &Cn [cmds]
Example:	AT &C3 *RS1 *SR1<CR>
Description:	Configures the behavior of the carrier detect signal.
Command	Function
&C0	CD forced high.
» &C1	CD normal.
&C2	CD forced high except during handshaking and disconnecting.
&C3	CD momentary follows DTR.
&C4	CD follows remote RTS signal.
&C5	CD Follows DTR signal. Forced low on disconnect.

CELLULAR ENHANCEMENTS
Type:	Register
Format:	AT [cmds] S91=n [cmds]
Example:	AT S91=0 &W<CR>
Description:	Configures modem to enhanced cellular mode
Command	Function
» S91=0	Disabled
S91=1	Enabled

COMPRESSION
Type:	Configuration
Format:	AT %Cn
Example:	AT I2 %C1 &B0 <CR>
Description:	Selects data compression.
Command	Function
%C0	Data compression disabled.
» %C1	Data compression enabled.

CTS SIGNAL
Type:	Configuration
Format:	AT [cmds] \Dn [cmds]
Example:	AT \D0<CR>
Description:	Selects the function of the CTS signal.
Command	Function
» \D0	CTS forced high.
\D1	CTS normal.
\D2	CTS interrupted for 2 seconds on disconnect.
\D3	CTS follows DTR.
\D4	CTS follows RTS

DISCONNECT BUFFER DELAY
Type:	Register
Format:	AT [cmds] S49=n [cmds]
Example:	AT S49=0<CR>
Default:	10
Range:	0-255
Unit:	1 second
Description:	Selects how long the modem will continue to transmit data in transmit buffer after receipt of disconnect signal

DISCONNECT IMMEDIATELY
Type:	Register
Format:	AT [cmds] S85=n [cmds]
Example:	AT S85=0 &W<CR>
Description:	Disconnect immediately on receipt of disconnect signal from DTE or diagnostic control panel.
Command	Function
» S85=0	Disabled.
S85=1	Enabled.

DISCONNECT ON LOSS OF CURRENT
Type:	Register
Format:	AT [cmds] S65=n [cmds]
Example:	AT S65=0<CR>
Description:	Causes the modem to disconnect if the telephone line’s current drops.
Command	Function
» S65=0	Disconnect after 8ms if current is lost.
S65=1	Disconnect after 90ms if current is lost.
S65=2	Disabled

DTE RATE CONTROL
Type:	Register
Format:	AT [cmds] S61=n [cmds]
Example:	AT S61=0 &W<CR>
Description:	Sets result of DTE CT111 rate control signal.
Command	Function
» S61=0	Disabled.
S61=1	Fallback 1.
S61=2	Fallback 2.

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 TYPE
Type:	Configuration
Format:	AT [cmds] \Qn [cmds]
Example:	AT \Q5<CR>
Description:	Sets type of flow control used by modem.
Command	Function
\Q0	Flow control disabled.
\Q1	Bidirectional XON/XOFF flow control enabled.
» \Q2	CTS flow control by DCE enabled.
\Q3	Bidirectional CTS/RTS flow control enabled.
\Q4	XON/XOFF flow control by DTE enabled.
\Q5	XON/XOFF flow control by DCE enabled.
\Q6	RTS flow control by DTE enabled.

INACTIVITY TIMER
Type:	Configuration
Format:	AT [cmds] \Tn [cmds]
Example:	AT\T20<CR>
Default:	0
Range:	0-255
Unit:	1 minute
Description:	Sets the length of time that the modem does not receive information before it disconnects.

LAP-M FRAME SIZE
Type:	Configuration
Format:	AT [cmds] \An [cmds]
Example:	AT \A3 %C1<CR>
Description:	Sets the maximum frame size for V.42 and MNP connections.
Command	Function
\A0	Maximum frame size is 64
\A1	Maximum frame size is 128
\A2	Maximum frame size is 192
» \A3	Maximum frame size is 256
\A4	Maximum frame size is 32
\A5	Maximum frame size is 16

LAP-M FRAME WINDOW
Type:	Register
Format:	AT [cmds] S89=n [cmds]
Example:	ATS89=6<CR>
Default:	0
Range:	1-9
Unit:	1 frame (beginning with 0=6 frames)
Description:	Sets the number of frames used in V.42 and V.42bis transmissions

LEASED LINE AUTO-RETRAIN
Type:	Register
Format:	AT [cmds] S82=n [cmds]
Example:	AT S82=0 &W<CR>
Description:	Allows modem to retrain to compensate for bad line quality in V.32bis or V.32terbo
Command	Function
» S82=0	Retrain enabled.
S82=1	Retrain disabled.

LEASED LINE BACKUP SPECIAL STANDBY
Type:	Register
Format:	AT [cmds] S98=n [cmds]
Example:	AT S98=0 &W<CR>
Description:	Allows leased line dial backup using a third modem.
Command	Function
» S98=0	Disabled
S98=1	Enabled

LEASED LINE DIAL BACKUP
Type:	Register
Format:	AT [cmds] S46=n [cmds]
Example:	AT S46=0 &F1<CR>
Description:	Automatically establishes switched line connection if leased line fails
Command	Function
» S46=0	Disabled.
S46=1	Enabled.

LEASED LINE BACKUP RECOVERY DELAY
Type:	Configuration
Format:	AT [cmds] S47=n &F1 [cmds]
Example:	AT S47=0 &F1 <CR>
Description:	After leased line failure, modem attempts to reconnect after specified delay.
Command	Function
» S46=0	Disabled.
S46=1	15 minute delay.
S46=2	60 minute delay.
S46=3	4 hour delay
S46=4	2 minute delay (test)
S46=5	Adv 15 minutes
S46=6	Adv 30 minutes
S46=7	Adv 60 minutes
S46=8	Adv 2 minutes (test)

LEASED LINE DISCONNECT LEVEL
Type:	Register
Format:	AT [cmds] S48=n [cmds]
Example:	AT S48=0 &W<CR>
Description:	Sets level carrier signal drops to before disconnect.
Command	Function
» S48=0	Disconnect at -43dBm
S48=1	Disconnect at -26dBm
S48=2	Disconnect at -33dBm

LEASED LINE SPEED
Type:	Register
Format:	AT [cmds] S44=n [cmds]
Example:	ATS44=18<CR>
Default:	18
Description:	Sets maximum leased line speed
Command	Function
S44=1	14.4Kbps V.32bis
S44=2	12.0Kbps V.32bis
S44=3	9600bps V.32bis
S44=4	7200bps V.32bis
S44=5	4800bps V.32bis
S44=6	2400bps V.22bis
S44=11	14.4Kbps V.33
S44=12	12.0Kbps V.33
S44=13	9600bps V.29
S44=14	7200bps V.29
S44=15	4800bps V.29
S44=16	4800bps V.27
S44=17	2400bps V.27bis
» S44=18	19.2Kbps V.32terbo
S44=19	16.8Kbps V.32terbo
S44=20	19.2Kbps TMp
S44=21	14.4Kbps TMp
S44=22	9600bps TMp
S44=23	7200bps TMp
S44=24	4800bps TMp
S44=25	2400bps TMp

LEASED LINE TRANSMISSION LEVEL
Type:	Register
Format:	AT [cmds] S45=n [cmds]
Example:	AT S45=15<CR>
Default:	0
Range:	0 - 15
Unit:	1 dBm
Description:	Sets the signal level for transmission when in leased line mode.

LINE TYPE
Type:	Configuration
Format:	AT [cmds] &Ln [cmds]
Example:	AT &L0 H1 DT555-1212<CR>
Description:	Selects line type.
Command	Function
» &L0	Switched line.
&L1	2-wire originate mode leased line.
&L2	4-wire originate mode leased line.
&L3	2-wire answer mode leased line.
&L4	4-wire answer mode leased line.

LOCAL ANALOG LOOPBACK
Type:	Register
Format:	AT [cmds] S52=n [cmds]
Example:	AT S52=0 &W<CR>
Description:	Modem executes local analog loopback on receipt of CT141 signal from DTE
Command	Function
» S52=0	Loopback disabled.
S52=1	Loopback enabled.

LOCK SERIAL PORT
Type:	Register
Format:	AT [cmds] S90=n [cmds]
Example:	AT S90=0<CR>
Description:	Sets operation of serial port speed.
Command	Function
» S90=0	Disabled.
S90=1	Serial speed follows connect speed.

NETWORK POSITION IDENTIFICATION
Type:	Register
Format:	AT [cmds] S74=n [cmds]
Example:	AT S74=0 &W<CR>
Description:	Identifies modem as either tributary or control
Command	Function
» S74=0	Identify as tributary
S74=1	Identify as control

PASSWORD REMOTE ACCESS
Type:	Register
Format:	AT [cmds] S56=n [cmds]
Example:	ATS56=06<CR>
Default:	None
Range:	00-99
Unit:	Password digits
Description:	Allows entry of the first two digits of remote access password.

PASSWORD REMOTE ACCESS
Type:	Register
Format:	AT [cmds] S57=n [cmds]
Example:	ATS57=06<CR>
Default:	None
Range:	00-99
Unit:	Password digits
Description:	Allows entry of the second two digits of remote access password.

PASSWORD REMOTE ACCESS
Type:	Register
Format:	AT [cmds] S58=n [cmds]
Example:	ATS58=06<CR>
Default:	None
Range:	00-99
Unit:	Password digits
Description:	Allows entry of the third two digits of remote access password.

PASSWORD REMOTE ACCESS
Type:	Register
Format:	AT [cmds] S59=n [cmds]
Example:	ATS59=06<CR>
Default:	None
Range:	00-99
Unit:	Password digits
Description:	Allows entry of the fourth two digits of remote access password.

REMOTE CONFIGURATION
Type:	Register
Format:	AT [cmds] S55=n [cmds]
Example:	AT S55=0 &W<CR>
Description:	Allows remote configuration by 3800 series modem.
Command	Function
» S55=0	Remote configuration enabled.
S55=1	Remote configuration disabled.

REMOTE DIGITAL LOOPBACK
Type:	Register
Format:	AT [cmds] S51=n [cmds]
Example:	AT S51=0 &W<CR>
Description:	Modem executes remote digital loopback on receipt of CT140 signal from DTE
Command	Function
» S51=0	Loopback disabled.
S51=1	Loopback enabled.

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 firmware 3 digit version number.
I2	Performs EPROM check

STORED PROFILE
Type:	Register
Format:	AT [cmds] S88=n [cmds]
Example:	AT S88=0 &W<CR>
Description:	Loads stored profile on disconnect.
Command	Function
» S88=0	Disabled.
S88=231	Disabled.
S88=1	Enabled.
S88=232	Enabled.

SWITCHED LINE SPEED
Type:	Register
Format:	AT [cmds] S41=n [cmds]
Example:	ATS41=20<CR>
Default:	20
Description:	Sets maximum line speed
Command	Function
S41=1	14.4Kbps V.32bis
S41=2	12.0Kbps V.32bis
S41=3	9600bps V.32bis, V.32
S41=4	7200bps V.32bis
S41=5	4800bps V.32bis, V.32
S41=6	2400bps V.22bis
S41=11	14.4Kbps V.33
S41=12	12000bps V.33
S41=13	9600bps V.29
S41=14	7200bps V.29
S41=15	4800bps V.29
S41=16	4800bps V.27
S41=17	2400bpsV.27bis
S41=18	19.2Kbps V.32terbo
S41=19	16.8Kbps V.32terbo
» S41=20	19.2Kbps TMp
S41=21	14.4Kbps TMp
S41=22	9600bps TMp
S41=23	7200bps TMp
S41=24	4800bps TMp
S41=25	2400bps TMp

TRANSMISSION LEVEL
Type:	Configuration
Format:	AT [cmds] &In [cmds]
Example:	AT &I26 &W<CR>
Default:	Unidentified
Range:	0-32, 99, 100
Unit:	-1 dBm
Description:	Sets the signal level for transmission
Note: 0-9 invalid in North America.

TRELLIS MULTIPOINT TRANSMIT PREEMPHASIS
Type:	Register
Format:	AT [cmds] S96=n [cmds]
Example:	AT S96=0 &W<CR>
Description:	Compensates for high frequency attenuation with amplification
Command	Function
» S96=0	Enabled
S96=1	Disabled

TRELLIS MULTIPOINT TRAIN TIME
Type:	Register
Format:	AT [cmds] S95=n [cmds]
Example:	AT S95=0 &W<CR>
Description:	Selects train time from tributary to control modem.
Command	Function
» S95=0	10 milliseconds
S95=1	20 milliseconds
S95=2	50 milliseconds
S95=3	100 milliseconds
S95=4	200 milliseconds
S95=5	300 milliseconds

V.25bis CODE SET
Type:	Register
Format:	AT [cmds] S62=n [cmds]
Example:	AT S62=0 &W<CR>
Description:	Sets coding type used in V.25bis mode.
Command	Function
» S62=0	ASCII
S62=1	EBCDIC

V.25bis IDLE CHARACTER
Type:	Register
Format:	AT [cmds] S63=n [cmds]
Example:	AT S63=0 &W<CR>
Description:	Sets V.25 idle fill type
Command	Function
» S63=0	Fill character is mark.
S63=1	Fill character is flag.

V.25bis NEW LINE CHARACTER
Type:	Register
Format:	AT [cmds] S64=n [cmds]
Example:	AT S64=0 &W<CR>
Description:	Sets V.25 new line character.
Command	Function
» S64=0	Carriage return and line feed.
S64=1	Carriage return.
S64=2	Line feed.

V.27 TRAIN
Type:	Register
Format:	AT [cmds] S72=n [cmds]
Example:	AT S72=0 &W<CR>
Description:	Sets train length.
Command	Function
» S43=0	Short
S43=1	Long

V.29 LINK TYPE
Type:	Register
Format:	AT [cmds] S94=n [cmds]
Example:	AT S94=0 &W<CR>
Description:	Selects point to point or multipoint operation
Command	Function
» S94=0	Point to point operation
S94=1	Multipoint operation

V.29 RETRAIN
Type:	Register
Format:	AT [cmds] S93=n [cmds]
Example:	AT S93=0 &W<CR>
Description:	Modem transmits training sequence on receipt of training sequence
Command	Function
» S93=0	Disabled
S93=1	Enabled

V.29 TRAIN
Type:	Register
Format:	AT [cmds] S92=n [cmds]
Example:	AT S92=0 &W<CR>
Description:	Allows retrain based on incoming data or training sequence. Required for tributary modem.
Command	Function
» S92=0	Disabled
S92=1	Enabled

V.32bis AUTO-RETRAIN
Type:	Register
Format:	AT [cmds] S76=n [cmds]
Example:	AT S76=0 &W<CR>
Description:	Selects action the modem will take during bad line quality on 32bis connection.
Command	Function
» S76=0	Auto retrain enabled.
S76=1	Auto retrain disabled.

V.32bis TRAIN
Type:	Register
Format:	AT [cmds] S43=n [cmds]
Example:	AT S43=0 &W<CR>
Description:	Sets train length for V.32bis and V32.
Command	Function
» S43=0	Long
S43=1	Short

V.42bis COMPRESSION CONTROL
Type:	Configuration
Format:	AT [cmds] "Hn [cmds]
Example:	AT "H3 &W<CR>
Description:	Controls V.42bis data compression
Command	Function
"H0	V.42bis disabled.
"H1	V.42bis when transmitting enabled.
"H2	V.42bis when receiving enabled.
» "H3	V.42bis when transmitting/receiving enabled.

V.54 DEVICE ADDRESS
Type:	Register
Format:	AT [cmds] S53=n [cmds]
Example:	ATS53=6<CR>
Default:	0
Range:	0-34
Unit:	Device address 0= disabled
Description:	Identifies the address of the modem in loopback test.

V.54 DEVICE TYPE
Type:	Register
Format:	AT [cmds] S54n [cmds]
Example:	AT S54=0 &W<CR>
Description:	Identifies modem’s network position.
Command	Function
» S54=0	Peripheral
S54=1	Intermediate

XON/XOFF PASS-THROUGH
Type:	Configuration
Format:	AT [cmds] \Xn [cmds]
Example:	AT \X7 O<CR>
Description:	Selects whether XON/XOFF signals are sent to remote modem.
Command	Function
» \X0	XON/XOFF signals trapped by local modem.
\X1	XON/XOFF passed through local modem.

DISPLAY STORED NUMBERS
Type:	Immediate
Format:	RLNn
Example:	RLN2<CR>
Description:	Display number in memory location n. If no number is given, all stored numbers will be displayed.