CONNECTIONS
Purpose	Location	Purpose	Location
Line out	CN1	Line in	CN2

BASE I/O ADDRESS SELECTION
Port	SW1/A	SW1/C	SW1/E	SW1/F
» COM1: (3F8h)	Off	On	Off	On
COM2: (2F8h)	On	Off	Off	On
COM3: (3E8h)	Off	On	On	Off
COM4: (2E8h)	On	Off	On	Off

INTERRUPT SELECTION
IRQ	SW/B	SW1/D	JP1
3	On	Off	Pins 2 & 4 closed
» 4	Off	On	Pins 2 & 4 closed
5	Off	Off	Pins 3 & 4 closed
7	Off	Off	Pins 1 & 2 closed
Note: Location of JP1 is unidentified.

ACCEPT RELIABLE MODE
Type:	Immediate
Format:	AT [cmds] \U [cmds]
Example:	AT \U B1<CR>
Description:	Accepts remote modem’s request for reliable link.

AUTO-RELIABLE FALLBACK CHARACTER
Type:	Configuration
Format:	AT [cmds] %An [cmds]
Example:	AT%A19<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
\C0	Data is discarded.
\C1	Data is buffered.
\C2	Data is discarded, modem returns to normal mode on receiving auto-reliable fallback character.

BIT-MAPPED REGISTER S14
Format		AT [cmds] S14=n [cmds]
Example:		ATS14=0<CR>
Default:		Unidentified
Range:		0-174
Unit:		Bit-mapped
Description:		Controls echo, result codes, result code display, dial mode, and answer/originate mode.
Bit	Value		Function
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 1		Smart mode. Dumb mode.
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=n [cmds]
Example:		ATS21=0<CR>
Default:		Unidentified
Range:		0-253
Unit:		Bit-mapped
Description:		Selects jack type, CTS signal, low DTR action, DCD signal, DSR signal, and the Long Space Disconnect function.
Bit	Value		Function
0	0 1		RJ-11 Not used.
1	0 1		Serial. Parallel.
2	0 1		CTS follows RTS. CTS forced high (synchronous only).
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=n [cmds]
Example:		ATS22=0<CR>
Default:		Unidentified
Range:		0-127
Unit:		Bit-mapped
Description:		Controls speaker volume and controls, and limits results codes.
Bit	Value		Function
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. Basic and connection speed result codes and dialtone detection enabled. All result codes except dialtone detection enabled. All result codes enabled.

BIT-MAPPED REGISTER S23
Format		AT [cmds] S23=n [cmds]
Example:		ATS23=0<CR>
Default:		Unidentified
Range:		0-189
Unit:		Bit-mapped
Description:		Grants/denies remote digital loopback, controls DTE rate and parity, and sets guard tone.
Bit	Value		Function
0	0 1		Remote digital loopback denied. Remote digital loopback allowed.
2, 1	00 01 10 11		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.
3	0		Not used.
5,4	00 01 10 11		Parity even. Space Parity. Parity odd. Mark/ No Parity.
7, 6	00 01 10		Guard tone disabled. Guard tone 550Hz enabled. Guard tone 1800Hz enabled.

BIT-MAPPED REGISTER S27
Format		AT [cmds] S27=n [cmds]
Example:		AT S27=0 <CR>
Default:		Unidentified
Range:		0 - 108
Unit:		Bit-mapped
Description:		Selects sync/async mode, Line type, internal clock, and ITU-T/Bell modes.
Bit	Value		Function
1, 0	00 01 10 11		Asynchronous mode, serial port speed follows connect speed. Asynchronous command mode and synchronous connect mode. Asynchronous command mode and synchronous connect mode, DTR dialing enabled. Asynchronous command mode on low DTR, synchronous connect mode on high DTR.
2	0 1		Dial up line. Leased line.
3	0		Not used.
5, 4	00 01 10		Internal DCE transmit clock source. External DTE transmit clock source. Remote DCE transmit clock source.
6	0 1		CCITT mode. Bell mode.

BIT-MAPPED REGISTER S36
Format		AT [cmds] S36=n [cmds]
Example:		ATS36=0<CR>
Default:		Unidentified
Range:		0 - 207
Unit:		Bit-mapped
Description:		Selects connect mode, flow control, XON/XOFF flow control, and DTE port flow control.
Bit	Value		Function
1, 0	00 01 10 11		Normal mode enabled. Direct mode enabled. Reliable mode enabled. Auto-reliable mode enabled.
2	0 1		Flow control disabled. Flow control enabled.
3	0 1		XON/XOFF signals trapped by local modem. XON/XOFF passed through local modem.
5, 4	0		Not used.
6, 7	00 01 10 11		Flow control disabled. XON/XOFF flow control enabled. CTS flow control to DTE enabled. RTS/CTS flow control enabled.

BIT-MAPPED REGISTER S38
Format		AT [cmds] S38=n [cmds]
Example:		ATS38=40<CR>
Default:		Unidentified
Range:		0 - 158
Unit:		Bit-mapped
Description:		Controls auto-reliable buffer, lock serial port speed, data echo, extended result codes, and transmit break.
Bit	Value		Function
1, 0	00 01 10		Data is discarded. Data is buffered. Data is discarded, modem returns to normal mode on receiving auto-reliable fallback character.
2	0 1		Serial speed locked. Serial speed follows connect speed.
3	0 1		Data echo disabled. Data echo enabled.
4	0 1		Extended result codes disabled. Extended result codes enabled.
6, 5	0		Not used.
7	0 1		300ms break not transmitted. 300ms break transmitted.

BIT-MAPPED REGISTER S40
Format		AT [cmds] S40=n [cmds]
Example:		ATS40=0<CR>
Default:		Unidentified
Range:		0 - 163
Unit:		Bit-mapped
Description:		Controls MNP block size, and break type.
Bit	Value		Function
1, 0	00 01 10 11		Maximum MNP block size is 64 characters. Maximum MNP block size is 128 characters. Maximum MNP block size is 192 characters. Maximum MNP block size is 256 characters.
2, 3, 4	0		Not used.
5, 6, 7	000 001 010 011 100 101		Online command mode enabled, send no break to remote modem. Break sent to remote modem and buffered cleared. Online command mode enabled, send no break to remote modem. Send break to remote modem immediately. Online command mode enabled, send no break to remote modem. Send break with transmitted data.

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

BREAK TYPE
Type:	Configuration
Format:	AT [cmds] \Kn [cmds]
Example:	AT \K5 <CR>
Description:	Configures action of break signal.
Command	Function
\K0	Online command mode enabled, send no break to remote modem.
\K1	Break sent to remote modem and buffered cleared.
\K2	Online command mode enabled, send no break to remote modem.
\K3	Send break to remote modem immediately.
\K4	Online command mode enabled, send no break to remote modem.
\K5	Send break with transmitted data.

COMPRESSION
Type:	Configuration
Format:	AT [cmds] %Cn [cmds]
Example:	AT \V1 %C0 &W<CR>
Description:	Selects data compression.
Command	Function
%C0	Data compression disabled.
%C1	Data compression enabled.

COMPRESSION
Type:	Register
Format:	AT [cmds] S41=n [cmds]
Example:	AT S41=0 &W<CR>
Description:	Selects data compression.
Command	Function
S41=0	Data compression disabled.
S41=1	Data compression enabled.

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

CONVERT TO RELIABLE MODE
Type:	Immediate
Format:	AT [cmds] \Y [cmds]
Example:	AT \Y<CR>
Description:	Initiates reliable mode link.

ECHO DATA
Type:	Configuration
Format:	AT [cmds] \En [cmds]
\Example:	AT \E0 <CR>
Description:	Enables modem to echo received data.
Command	Function
\E0	Data echo disabled.
\E1	Data echo enabled.

EXTENDED RESULT CODES
Type:	Configuration
Format:	AT [cmds] \Vn [cmds]
Example:	AT \V0 %C1<CR>
Description:	Selects extended result codes.
Command	Function
\V0	Extended result codes disabled.
\V1	Extended result codes enabled.

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 \Q0 A <CR>
Description:	Sets type of flow control used by modem.
Command	Function
\Q0	Flow control disabled.
\Q1	XON/XOFF flow control enabled.
\Q2	CTS flow control to DTE enabled.
\Q3	RTS/CTS flow control enabled.

INACTIVITY TIMER
Type:	Configuration
Format:	AT [cmds] \Tn [cmds]
Example:	AT\T20<CR>
Default:	Unidentified
Range:	0-90
Unit:	1 minute
Description:	Sets the length of time that the modem does not receive information before it disconnects.

LOCK SERIAL PORT
Type:	Configuration
Format:	AT [cmds] \Jn [cmds]
Example:	AT %L3 %B14 \J0<CR>
Description:	Sets operation of serial port speed.
Command	Function
\J0	Serial speed locked.
\J1	Serial speed follows connect speed.

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	Maximum MNP block size is 64 characters.
\A1	Maximum MNP block size is 128 characters.
\A2	Maximum MNP block size is 192 characters.
\A3	Maximum MNP block size is 256 characters.

ON-LINE IN RELIABLE MODE
Type:	Immediate
Format:	AT [cmds] \O
Example:	AT \O <CR>
Description:	Returns to on-line and requests reliable mode connection.

SWITCH TO MNP MODE
Type:	Immediate
Format:	AT [cmds] \Z [cmds]
Example:	AT \Z &W<CR>
Description:	Switches to normal mode from MNP mode.

TEST MODES
Format		AT [cmds] S16=n [cmds]
Example:		ATS16=0<CR>
Default:		Unidentified
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.

XON/XOFF PASS-THROUGH
Type:	Configuration
Format:	AT [cmds] \Xn [cmds]
Example:	AT \X0 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.