Advanced Modem Control Information for the IBM 28.8(V.34) / 14.4 Kbps Data/FAX Modems IBM Corporation Copyright 1994 TABLE of CONTENTS TRADEMARKS INTRODUCTION MODEM OPERATION MODEM COMMANDS SETTING UP THE COMMAND LINE COMMAND ACKNOWLEDGMENT BASIC COMMANDS DIAL COMMAND MODIFIERS MAKING A CALL CONTROLLING THE MODEM OVERVIEW ON-LINE STATE ESCAPE TO COMMAND MODE RETURN TO ON-LINE STATE REPEATING THE LAST COMMAND OMITTING A PARAMETER RESULT CODES COMMAND SYNTAX AT COMMAND REFERENCE AT COMMAND REFERENCE SUMMARY BASIC COMMANDS +++ ESCAPE SEQUENCE A/ RE-EXECUTE COMMAND IDENTIFICATION AND CONFIGURATION IN IDENTIFICATION ZN MODEM RESET &FN RECALL FACTORY PROFILE &JN TELEPHONE JACK CONTROL &V VIEW CONFIGURATION &WN STORE USER PROFILE &YN DEFAULT USER PROFILE &ZN=X STORE PHONE NUMBER SPEAKER CONTROLS LN SPEAKER VOLUME MN SPEAKER CONTROL DIAL COMMANDS A ANSWER CN CARRIER CONTROL DN DIAL HN DISCONNECT (HANG-UP) P SET PULSE DIAL DEFAULT T SET TONE DIAL DEFAULT YN LONG SPACE DISCONNECT SERIAL PORT CONTROL &CN DCD CONTROL &DN DTR OPTION &KN DATA FLOW CONTROL &MN COMMUNICATION (ASYNCHRONOUS/SYNCHRONOUS) MODE &RN RTS/CTS (HARDWARE) FLOW CONTROL &SN DSR OVERRIDE &XN SELECT SYNCHRONOUS CLOCK SOURCE \GN MODEM TO MODEM (SOFTWARE) FLOW CONTROL COMMAND RESPONSE AND RESULTS CODES EN COMMAND ECHO QN RESULT CODE ON/OFF VN RESULT CODE FORMAT XN EXTENDED RESULT CODE DATA COMMANDS BN CCITT OR BELL SELECTION FN SELECT MODULATION NN AUTOMODE ENABLE (AUTOMATIC LINE SPEED DETECTION) ON RETURN TO ON-LINE DATA MODE WN NEGOTIATION PROGRESS (CONNECT MESSAGE) CONTROL %EN AUTO-RETRAIN CONTROL %L LINE SIGNAL LEVEL %Q LINE SIGNAL QUALITY &GN SELECT GUARD TONE &QN COMMUNICATION MODE SELECTION (SYNC/ASYNC MODE) +MS SELECT MODULATION MNP OPERATION \AN SELECT MAXIMUM MNP BLOCK SIZE \BN TRANSMIT BREAK \KN BREAK CONTROL \NN PROTOCOL NEGOTIATION SELECTION DATA COMPRESSION %CN ENABLE/DISABLE DATA COMPRESSION MNP 10 OPERATION :EN COMPROMISE EQUALIZER SETTING *HN LINK NEGOTIATION SPEED -KN MNP EXTENDED SERVICES )MN CELLULAR POWER LEVEL ADJUSTMENT @MN INITIAL CELLULAR POWER LEVEL SETTING -QN ENABLE FALLBACK TO V.22BIS/V.22 MODEM TEST AND DIAGNOSTIC COMMANDS &TN TEST MODE FAX COMMANDS S REGISTERS READING A REGISTER VALUE CHANGING A REGISTER VALUE ACCESSING A REGISTER REPEATEDLY HOW TO SET BIT-MAPPED REGISTERS S REGISTER COMMANDS SN? READ AN S REGISTER SN=X WRITE AN S REGISTER VALUE SN SELECT A SPECIFIC S REGISTER =X WRITE TO CURRENTLY SELECTED S REGISTER ? READ CURRENTLY SELECTED S REGISTER S REGISTER DEFINITIONS S0 AUTO ANSWER S1 RING COUNTER S2 ESCAPE CHARACTER S3 CARRIAGE RETURN CHARACTER S4 LINE FEED CHARACTER S5 BACKSPACE CHARACTER S6 DELAY TIME FOR BLIND DIALING S7 DELAY TIME FOR CARRIER DETECT FOLLOWING DIALING S8 PAUSE TIME FOR “,” WITHIN DIAL STRING S9 CARRIER DETECT RESPONSE TIME S10 CARRIER LOSS DISCONNECT DELAY S11 DTMF TONE DURATION S12 ESCAPE CODE GUARD TIME S13 RESERVED S14 GENERAL BIT MAPPED OPTIONS S15 RESERVED S16 DIAGNOSTIC STATUS REGISTER S17 RESERVED S18 TEST TIMER S19 AUTOSYNC BIT MAPPED OPTIONS S20 AUTOSYNC HDLC ADDRESS OR BSC SYNC CHARACTER S21 V.24/GENERAL BIT MAPPED OPTIONS/STATUS S22 SPEAKER CONTROL/RESULTS STATUS S23 GENERAL BIT MAPPED OPTIONS STATUS S24 SLEEP INACTIVITY TIMER S25 DTR DETECTION DELAY S26 RTS TO CTS DELAY S27 MODE SELECTION S28 MODE SELECTION II S29 FLASH MODIFIER S30 AUTO DISCONNECT INACTIVITY TIMER S31 BIT MAPPED OPTIONS STATUS S32 XON CHARACTER S33 XOFF CHARACTER S34 - S35 RESERVED S36 LAPM FAILURE CONTROL S37 DESIRED LINE CONNECTION SPEED S38 FORCED HANG-UP DELAY S39 FLOW CONTROL S40 MNP ERROR CORRECTION CONTROLS S41 COMPRESSION CONTROLS S42 - S45 RESERVED S46 V.42BIS DATA COMPRESSION S47 RESERVED S48 V.42 NEGOTIATION S49 - S81 RESERVED S82 BREAK HANDLING OPTION S83 - S85 RESERVED S86 CONNECTION FAILURE CODE S87 - S90 RESERVED S91 DATA TRANSMIT LEVEL CONTROL S92 FAX TRANSMIT LEVEL CONTROL S93 - S94 RESERVED S95 RESULT CODE CONTROL S96 - S97 RESERVED S201 CELLULAR TRANSMIT LEVEL USER NOTES COMMON SETUP STRINGS TRADEMARKS The following terms denoted by an asterisk (*), used in this publication, are trademarks of other companies as follows: o Hayes is a trademark of Hayes Microcomputer Products, Incorporated o AutoSync is a registered trademark of Hayes Microcomputer Products, Incorporated o MNP is a trademark of Microcom, Incorporated INTRODUCTION The following sections provide additional detailed information about your modem. You can learn how to interact with your modem using the "AT" Command Language. You will also learn how your modem is configured from the factory, and how you can change its configuration with "AT" commands and by setting S registers. In the section "User Notes", we have provided information we have learned through our product testing that might be useful to users of certain communications packages. MODEM OPERATION Modem Commands The modem supports the standard and extended Hayes* AT command set. The AT prefix (also known as the Attention Code), signals the modem that one or more commands are to follow. These commands are industry standard language used to communicate with the modem. Your modem is always either in the command mode, or the on-line mode. The modem starts up in command mode when it is first switched on. Commands are only accepted by the modem when it is in command mode. Commands input when the modem is on-line, are treated as data, not as commands. Commands may be entered from the terminal mode of most communications software packages. Settings made via AT commands are automatically reused by the modem until another command is received to change them, or the modem is turned off. Setting up the Command Line All commands except two, must begin with the characters AT. The two exceptions are the escape sequence (+++), and the repeat command (A/). The command line prefix (letters AT) and the command sequences which follow, can be typed in upper case, or lower case, but case must not be mixed. More than one command can be typed on one line, separated by spaces if you wish for easier reading. The spaces are ignored by the modem's command interpreter. The maximum number of characters on any command line is 58 characters including "A" and "T". Spaces, carriage return, and any line feed characters do not go into the buffer, and don't count against the 58 character limitation. If a syntax error is found anywhere in the command line, the modem returns an ERROR result code, and the command input beyond the error, is ignored. Command Acknowledgment The modem will acknowledge most commands almost immediately. As soon as you type in a command ending with the carriage return character your modem will respond with OK. There are other acknowledgment messages (result codes) as well. They are described in the section Command Response and Results Codes. Basic Commands With the following basic AT commands, you can make calls directly, select the dialing method (tone or pulse), control the speaker volume, and perform a number of other basic modem operations. Instructions on the full set of commands are provided in the section "AT Command Reference". IMPORTANT: You must be in the Command mode of your communication software to use the AT commands. Refer to the documentation that came with your communications software for information on entering the Command mode. AT This prefix begins all but two commands you issue to the modem locally, and tells the modem "ATtention! commands to follow". D Dial. Use the D command to dial a telephone number from the command line. The format of the command is as follows: ATD {string} The string parameter can contain up to 43 characters. The dial modifiers instruct a modem how to place the call. Do not use any added characters, such as parentheses or hyphens in the phone number. +++ Escape Character Sequence. After you have connected to another modem, you may need to return to command mode to adjust the modem configuration, or more commonly, to hang up. To do this leave your keyboard idle (press no keys) for at least one second, then press "+" three times. This is one of the two commands that do not use the AT prefix, or a carriage return to enter. After a moment, the modem will respond with OK indicating you have been returned to Command mode. A/ Repeat. This command does not use the AT prefix nor does it require a carriage return to enter. Typing this command causes the modem to repeat the last command line entered, and is most useful for redialing telephone numbers which are busy. &Fn Factory Defaults. This command (in which n=0 or 1) returns all parameters to the selected set of factory defaults. H Hang Up. This command tells the modem to go "on-hook", or to disconnect the telephone line. O On-Line. This command returns the modem to the on-line mode and is usually used after the escape sequence (+++) to resume communication. Zn Reset Modem. This command (in which n=0 or 1) resets the modem to the configuration profile stored in non- volatile memory location 0 or 1. Dial Command Modifiers Command modifiers define additional parameters to the modem that instruct the modem to perform certain functions automatically when dialing a phone number. They are only valid when they are contained in a dial string (that follows the D command). The commands that are used to accomplish this task are called dial modifiers, and are placed in the dial string prior to issuing the command. Syntax: ATD{dial modifier} 1234567 Basic dial modifiers are: P Pulse dialing. Also known as rotary dialing, this dial modifier follows the D command and precedes the telephone number to tell the modem to dial the number using pulse service. T Tone dialing. This modifier selects the tone method of dialing using DTMF tones. Note: Tone and pulse dialing can also be combined in a dial command line when both dialing methods are required. ; Resume command mode after dialing. If you need to dial a number that is too long to be contained in the command buffer (45 characters for the D command), use the (;) modifier to separate the dial string into multiple dial commands. All but the last command must be end with the ; modifier. For example: Keyboard: ATDT9551234; Display: OK ATDT123456789; OK ATDT12345678901 , Pause While Dialing. The comma (,) dial modifier causes the modem to pause while dialing. The modem will pause the number of seconds specified in S-Register S8 and then continue dialing. If a pause time longer than the value in S-Register S8, it can be increased by either inserting more than one (,) in the dial command line or changing the value of S-Register S8. In the following example, the command accesses the outside (public) telephone line with the 9 dial modifier. Because the comma (,) dial modifier is present, the modem delays before dialing the telephone number 5551212. ATD 9, 5551212< Enter> ! Using the Hook Flash. The exclamation mark (!) dial modifier causes the modem to go on-hook (hang up) for one-half second and is equivalent to holding down the switch-hook on your telephone for one-half second. This feature is useful when transferring calls. W Wait for a Subsequent Dial Tone. The W dial modifier causes a modem to wait for an additional dial tone before dialing the numbers that follow the W. The length of time the modem waits depends on the value in S-Register S7. The modem can be instructed to dial through PBXs (Private Branch Exchanges) or long- distance calling services that require delays during dialing. This can be done with the W command to wait for a secondary dial tone or with a comma (,) command to pause for a fixed time and then dial. An example of a dial command line when dialing through a PBX follows: Syntax: ATDT 9 W 1 2155551212 Making a Call The following examples show how to place a call using several of the dial modifiers. ATD 1234567 The modem dials the telephone number 1234567 and then waits for a carrier from a distant, or remote modem. If no carrier is detected within a given time (as defined by the initial settings in S-Register 6), then the modem automatically releases the line and sends a NO CARRIER result code. If a carrier is detected, the modem gives a CONNECT result code and goes on-line, allowing communications with the remote modem. The connection between the two modems ends when any of the following occurs causing the modem to hang up, return to command mode, and send the NO CARRIER response: o The local modem loses the carrier signal from the remote modem. o The Hang Up command (H) is sent. o The DTR interface signal is dropped between the local DTE and modem when the &D2 or &D3 command is in effect. AT &F1DT9,P5551234 This command restores the factory default settings, dials, using tones, a 9 to access an outside line, pauses briefly, then pulse dials the number 555-1234. Manual Dialing with the Telephone To manually dial the phone, you should be in your communications software’s command mode. 1. Lift the receiver of the telephone and dial the number you wish to call. 2. Type ATH1 and press to connect the modem and then hang up the receiver. 3. Type AT0 and press to tell the modem to go on line. Manual Answer When the automatic answer feature (S-Register S1) is not being used, incoming calls can be answered manually by typing: ATA When an incoming call is received. The modem will answer the incoming call and the on-line mode. CONTROLLING THE MODEM Overview This reference guide has been published in order to provide you with the information needed to set the parameters and variables that are used to control the operation of your modem. On-line State To transmit or receive data, the modem must be in the on-line state. When placing a call, the modem is put on- line with the dial command. At the remote end, the modem goes on-line when it is instructed to answer a call automatically by setting the S-Register S0 equal to any number greater than 0 and less than 255. You can also perform this function with the ATA command. Escape to Command Mode After a connection has been established with a remote modem, you can return to command mode without breaking that connection by typing the escape sequence. The escape sequence consists of three characters (+++). It is not necessary to begin this sequence with the attention code, or by pressing after typing the escape code. See the "AT Command Reference" for more information. Return to On-line state The modem can be returned to the on-line state after the escape sequence has been issued. To return the modem to the on-line state, issue the ATO command. To return the modem on-line and then initiate an equalizer retrain sequence, use the ATO1 command. Repeating the last Command Each command sent to the modem remains in the command buffer until the next command is sent, or until power to the modem is turned off. To repeat the last command issued, type the command A/. The A/ command is not preceded by the AT characters or followed by pressing . See the command reference for more information. Omitting a Parameter Some command require a parameter to completely define them. If a parameter is omitted from a command that requires one, the command will use the default value. Result Codes A response is displayed on your screen by the modem, indicating the result after it processes, or tries to process a command. These result codes display the status of the modem, or the progress of a call sequence, and can take the form of either words or digits. The default consists of word responses that are defined by the ATV1 command (see command "Result Code Format"). To receive digit responses rather than words, use the ATV0 command. To disable responses entirely, use the ATQ1 command (see command "Result Code On/Off"). A complete list of responses is provided and discussed under in the section Command Response and Results Codes. Command Syntax All control commands to the modem are prefixed with either AT or at and terminated by a carriage return (Enter). Mixed case set ("At" or "aT") is not allowed. The "AT" sequence is called the "ATTENTION COMMAND". The Attention command precedes all other commands except RE-EXECUTE (A/) and the ESCAPE (+++)code. Several commands which are preceded by AT can be entered in a single line followed by the carriage return character. Spaces can be inserted between commands to increase readability, but will not be stored in the command buffer. The Backspace character can be used to erase mistakes but is not saved as part of the contents of the command buffer in terminal applications. Unsupported commands will be logged and an "OK" or "ERROR" will be returned. Commands will only be accepted by the modem once the previous command has fully executed. A command line may be aborted at any time by entering "CTRL X". The AT sequence may be followed by any number of commands in sequence, except for commands such as Z, D, or A. Commands following Z, D, or A on the same command line will be ignored. The maximum number of characters on any command line is 58 (including A and T). AT COMMAND REFERENCE AT Command Reference Summary %Cn Enable/Disable Data Compression %En Auto-Retrain control %L Line Signal Level %Q Line Signal Quality &Cn DCD Control &Dn DTR Option &Fn Recall Factory Profile &Gn Select Guard Tone &Jn Telephone Jack Control &Kn Data Flow Control &Mn Communication (Asynchronous/Synchronous) Mode &Qn Communication Mode Selection (Sync/Async Mode) &Rn RTS/CTS (Hardware) Flow Control &Sn DSR Override &Tn Test Mode &V View Configuration &Wn Store User Profile &Xn Select Synchronous Clock Source &Yn Default User Profile &Zn=x Store Phone Number )Mn Cellular Power Level Adjustment *Hn Link Negotiation Speed +++ Escape Sequence +MS Select Modulation :En Compromise Equalizer Setting ? Read Currently Selected S Register @Mn Initial Cellular Power Level Setting \An Select Maximum MNP Block Size \Bn Transmit Break \Gn Modem to Modem (Software) Flow Control \Kn Break Control \Nn Protocol Negotiation Selection A Answer A/ Re-execute Command Bn CCITT or Bell Selection Cn Carrier Control Dn Dial En Command Echo Fn Select Modulation Hn Disconnect (Hang-up) In Identification -Kn MNP Extended Services Ln Speaker Volume Mn Speaker Control Nn Automode Enable (Automatic Line Speed Detection) On Return to On-Line Data Mode P Set Pulse Dial Default -Qn Enable Fallback to V.22bis/V.22 Qn Result Code On/Off Sn Select a Specific S Register Sn=x Write an S Register Value Sn? Read an S Register T Set Tone Dial Default Vn Result Code Format Wn Negotiation Progress (Connect Message) Control Xn Extended Result Code Yn Long Space Disconnect Zn Modem Reset Basic Commands +++ Escape Sequence The escape sequence causes the modem to go to the off- line command state from the on-line data state. After this escape sequence, the modem can accept user's AT commands. The escape sequence consists of three escape code that is defined by S-Register 2 (default value: decimal 43(+)). Do not enter any character before and/or after the "+++" for a guard time specified by S-Register 12 (default: 1 second). The duration between escape codes must also be within the guard time. After the modem recognizes a valid escape sequence, an "OK" result code is returned. If an escape sequence is valid, the escape code is transmitted to a remote modem. The ATO command is used to go back to on-line data state. For example: ATD 0123456 CONNECT 19200 <----> ( 1 sec pause ) +++ - Without 1 sec pause between escape codes ( 1 sec pause ) OK - On-line command state ATH0 - Disconnect the line OK A/ Re-execute Command This command re-executes the previous command processed by the modem. This command will be useful to re-dial without entering a dial string when a line is busy or unanswered. This command must appear alone on the command line. This command is not preceded by "AT", or followed by . Identification and Configuration These commands are used in the identification and configuration of the modem. In Identification This command instructs the modem to return its product identification information. Command Options: I0 Returns the Rockwell product code. I1 Reports the 3 digits pre-computed ROM checksum code. I2 Calculates a checksum of the modem firmware ROM and indicates OK or ERROR for the checksum validity. I3 Returns the modem ROM version. I4 Returns the modem identifier string. I5 Reports the country code parameter (e.g., "022"). I6 Returns the modem data pump model. I7 Reports the DAA code (e.g., "000" for U.S. and Canada). Zn Modem Reset This command resets the modem and recalls the stored configuration as defined at power on time. Default: Z0 Z0 Reset and recall stored user profile 0. Z1 Reset and recall stored user profile 1. &Fn Recall Factory Profile This command reloads the factory default profile. The configuration profile contains a subset of S-registers. Default: &F0 &F0 Recall Factory Profile 0. &F1 Recall Factory Profile 1. &Jn Telephone Jack Control This command is only included for compatibility and performs no function. The value is written into S- Register 21 bit 1. &J0 &J0 Command &J1 &J1 Command &V View Configuration This command displays the current active configuration, stored user profiles, and the first four stored telephone numbers. Applications may change these profile. For example: ACTIVE PROFILE: B1 E1 F0 L2 M1 N1 P Q0 V1 W1 X4 Y0 &C1 &D2 &G0 &K3 &Q5 &R0 &T4 &X0 &Y0 S00:000 S01:000 S02:043 S03:013 S04:010 S05:008 S06:002 S07:050 S08:002 S09:006 S10:014 S12:050 S18:000 S24:100 S25:005 S26:001 S36:007 S37:000 S38:020 S44:104 S46:138 S48:007 S95:044 STORED PROFILE 0: B1 E1 F0 L2 M1 N1 P Q0 V1 W1 X4 Y0 &C1 &D2 &G0 &K3 &Q5 &R0 &T4 &X0 S00:000 S02:043 S06:002 S07:050 S08:002 S09:006 S10:014 S12:050 S18:000 S24:100 S36:007 S37:000 S40:104 S41:003 S46:138 S48:007 S95:044 STORED PROFILE 1: B1 E1 F0 L2 M1 N1 Q0 T V1 W1 X4 Y0 &C1 &D2 &G0 &K3 &Q5 &R1 &T4 &X0 S00:000 S02:043 S06:002 S07:050 S08:002 S09:006 S10:014 S12:050 S18:000 S24:100 S36:007 S37:000 S40:104 S41:003 S46:138 S48:007 S95:044 TELEPHONE NUMBERS: 0 = ____________________ 2 = ____________________ 1 = ____________________ 3 = ____________________ OK If the modem's non-volatile memory is detected as defective by the modem's NVRAM test, the modem will display : NVRAM FAILED OR NOT INSTALLED &Wn Store User Profile This command stores the current, active configuration including S-Registers into non-volatile memory as stored user's profile 0 or 1. Storable parameters can be viewed by &V command. Stored parameters can be recalled into active configuration by Zn command or at power on. &W0 Store active configuration as user's profile 0. &W1 Store active configuration as user's profile 1. &Yn Default User Profile This command selects which of two user's profiles will be loaded into the active configuration following Power on Reset. Default: &Y0 &Y0 Selects power up configuration as user's profile 0. &Y1 Selects power up configuration as user's profile 1. &Zn=x Store Phone Number This command stores up to 4 telephone number dial strings into one of 4 non-volatile memory locations specified by n. This stored phone number can be used for later abridged dialing with the DS=n command. n: Entry number (range 0-3) x: dial string <= 35 digits (including dial modifiers) Speaker Controls These commands are used to control the system speaker for the IBM 28.8(V.34) / 14.4 Kbps Data/FAX Modems. Ln Speaker Volume This command controls the modem speaker volume when the speaker is turned on (see Mn command). The parameter if valid, is written to S-register 22 bits 0 and 1. Default: L2 L0,1 Selects low speaker volume. L2 Selects medium speaker volume. L3 Selects high speaker volume. Mn Speaker Control This command selects when the modem speaker will be on or off. The parameter if valid, is written to S- register 22 bits 2 and 3. Default: M1 M0 The speaker is always off. M1 Enables the speaker during call establishment, but off once the carrier is detected. M2 The speaker is always on. M3 Disables the speaker during the dialing period and receiving carrier, but on during answering. Dial Commands The following commands discuss modem dialing A Answer The modem will go off hook, transmit the answer tone, and wait for a carrier from the remote modem. Cn Carrier Control This command is included for compatibility only and has no effect other than returning a result code. Dn Dial Puts the modem into origination mode, allowing it to work as an automatic dialer for connection to another modem. The string n contains the telephone number and the following optional “dial modifiers”. The string n must be less than 45 characters excluding spaces, hyphens, and parenthesis, which can be used for clarity. 0-9 DTMF digits 0 to 9 * The "star" digit (tone dialing only) # The "gate" digit (tone dialing only A-D DTMF digits A, B, C, D. J Perform MNP 10 link negotiation at 1200 bps (this call only). See *H command. K Enable power level adjustment during MNP 10 link negotiation (for this call only). See )Mn command. L Re-dial last number. The L must be immediately after the D with the following characters ignored. P Selects Pulse dialing. Only digits 0-9 can be entered in pulse dial mode. R Reverse dial mode. This command accepted but not acted upon. S=n Dial stored number. Dials the number stored in location n (0-3). See &Z command. T Select tone dialing. Any digit 0- 9,*,#,A,B,C,D, etc. may be dialed. W Wait for dial tone. The modem waits for dial tone before processing the dial string (wait time specified by value in S-register 7). , Pause. Causes the modem to pause for the time specified by S-Register 8 before processing the next character in the dial string. ! Flash hook. This causes the modem to go on- hook for the time defined by the value of S- Register 29, and then return off-hook. @ Wait for silence. The modem will wait for five seconds of silence before dialing the remaining dial string (wait time specified by value in S-register 7). ; Return to idle state. Modem returns to command mode after dialing a number without disconnecting the call. & Wait for "bong" tone for credit card dialing before continuing with the remaining dial string (wait time specified by value in S- register 7). ^ Toggles calling tone enable/disable; applicable to current dial attempt only. () Ignored, may be used to format the dial string. - Ignored, may be used to format the dial string. Ignored, may be used to format the dial string. Hn Disconnect (Hang-up) This command provides switch hook control. Default: H0 H0 Instructs the modem to disconnect or hang-up. H1 Instructs the modem to go off-hook and enter command mode. P Set Pulse Dial Default This command forces pulse dialing until the next T dial modifier or T command is received. Sets S-Register 14 bit 5. T Set Tone Dial Default This command forces DTMF dialing until the next P dial modifier or P command is received. Clears S-Register 14 bit 5. Yn Long Space Disconnect This command determines whether the modem hangs up when it receives a long space signal (greater than 1.6 seconds) from the remote modem. If enabled, the modem will send a 4 second space signal to the remote modem before hanging up. The parameter if valid is written to S-Register 21 bit 7. Default: Y0 Y0 Disable long space disconnect signaling. Y1 Enable long space disconnect signaling. Serial Port Control The IBM 28.8(V.34) / 14.4 Kbps Data/FAX Modems can determine the speed, parity, and stop bits from the serial port connection. The modem automatically detects the serial data speed between 300 and 115,200 bps with the following formats: Data Parity Stop Bits Total Length Length ------ ------ --------- ------------ 7 None 2 10 7 Odd 1 10 7 Even 1 10 7 Mark 1 10 7 Space 1 10 8 None 1 10 8 Odd 1 11 8 Even 1 11 The modem also has the capability of automatically adjusting the baud rate to the internal serial port to physical carrier speed. The user application must adjust the baud rate of the internal serial port to it by detecting carrier speed after CONNECT xxxx message. This command setting is valid for reliable (error corrected) link and normal mode connections. The baud rate adjust feature is always active for direct mode connection. &Cn DCD Control This command controls the behavior of the DCD (Data Carrier Detect) signal of the internal serial port. The parameter if valid is written to S-register 21 bit 5. Default: &C1 &C0 DCD is always on. &C1 DCD will track the state of the data carrier from the remote modem. &Dn DTR Option This command controls the modem response to the serial port’s Data Terminal Ready (DTR) signal. This command interprets the ON and OFF transitions of the DTR signal from the DTE in accordance with the parameters as defined by n. The parameter value if valid, is written to S-register 21 bits 3 and 4. The &Dn command interprets DTR drop according to the current settings of &Qn. S-register 25 also defines the length of time DTR is ignored before taking action. Default: &D2 ---------------------------------------- &D0 &Q0, Ignore the DTR signal (assumed on) &Q5, &Q6 ---------------------------------------- &Q1, DTR drop causes the modem to hang up. Auto answer &Q4 not affected ---------------------------------------- &Q2, DTR drop causes the modem to hang up. Auto answer &Q3 is inhibited ---------------------------------------- &D1 &Q0, DTR drop is interpreted by themodem as if the &Q1, escape sequence has been entered.Returns to command &Q4, state without disconnecting. &Q5, &Q6 ---------------------------------------- &Q2, DTR drop causes the modem to hang up. Auto answer &Q3 is inhibited ---------------------------------------- &D2 &Q0 through &Q6, DTR drop causes the modem to hang up. Auto answer is inhibited. ---------------------------------------- &D3 &Q0, DTR drop causes the modem to perform a soft reset &Q1, as if the Z command were received. The &Q4, &Yn setting determines which profile is loaded. &Q5, &Q6 ---------------------------------------- &Q2, DTR drop causes the modem to hang up. Auto answer &Q3 is inhibited ---------------------------------------- &Kn Data Flow Control This command determines how the modem controls data flow between the system and the modem. The parameter if valid is written to S-register 39 bits 0, 1, and 2. For example, if the speed between the system unit and the modem is 19200 bps, and the speed between the local and remote modem is 2400 BPS, the transmit buffer of the modem is likely to be overflow when the system is sending large amounts of data. To prevent an overflow and subsequent loss of data, the modem either sends a XOFF character or drops the CTS signal to signal that the system should stop data sending. When enough space is available in the modems transmit buffer, the modem either sends a XON character or raises CTS to signal that application could resume data sending. For binary data transfer CTS/RTS flow control should be selected since the modem cannot distinguish the user's data from XON/XOFF characters. Flow control is not used for direct mode connection. Default: &K3 &K0 Disables flow control. &K1 Error &K2 Error &K3 Enables RTS/CTS flow control. Flow control is active in both sending and receiving direction. &K4 Enables XON/XOFF flow control. Flow control is active in both sending and receiving direction. &K5 Enables transparent XON/XOFF flow control. XON/XOFF character which is sent from the system unit will be processed for flow control and also sent to the remote modem. Flow control is active in both sending and receiving direction. &K6 Enables both RTS/CTS and XON/XOFF flow control. &Mn Communication (Asynchronous/Synchronous) Mode Determines the DTR operating mode. The modem treats the &M command as a subset of the &Q command. This command is used to choose between asynchronous, synchronous, or direct dial modes while the modem is in the command state. Only Asynchronous mode is supported. The value 000b is written to S-register 27 bits 3, 1, and 0. Default: &M0 &M0 Selects direct asynchronous mode. &Rn RTS/CTS (Hardware) Flow Control This command determines how the modem controls CTS (Clear to Send). CTS operation is modified if hardware flow control is selected. The parameter if valid, is written to S-register 21 bit 2. Default: &R1 &R0 In synchronous mode, CTS tracks the state of RTS. In asynchronous mode, CTS acts according to V.25 handshake. &R1 In synchronous mode, CTS is always ON (RTS transitions are ignored). In asynchronous mode, CTS will only drop if required by flow control. &Sn DSR Override This command selects how the modem will control Data Set Ready (DSR). The parameter if valid, is written to S-register 21 bit 6. Default: &S0 &S0 Causes DSR signal to be active at all times. &S1 Causes DSR signal to be active after answer tone has been detected, and inactive after the carrier has been lost. &Xn Select Synchronous Clock Source Selects the source of the transmission clock for the synchronous mode of operation. The parameter value, if valid, is written to S27 (bits 4 and 5). In asynchronous mode, the transmission and receipt clocks are turned off. Default: &X0 &X0 Selects internal timing. &X1 Selects external timing. &X2 Selects slave receiving timing. The transmission clock signal is derived from the incoming carrier. \Gn Modem to Modem (Software) Flow Control This command enables or disables software flow control using XON/XOFF, between your modem and the remote modem. During a reliable (error corrected) connection this setting is ignored. Default: \G0 \G0 Disables modem port XON/XOFF flow control \G1 Enables modem port XON/XOFF flow control Command Response and Results Codes These commands control the responses to commands issued the modem. En Command Echo This command determines whether the modem echoes characters back to the DTE, when in command mode. The parameter if valid is written to S-register 14 bit 1. Default: E1 E0 Inhibits the command echo - If your system application does not expect the echo, use this setting, otherwise, entering "AT" causes your terminal to display "AATT". E1 Enables the command echo. Qn Result Code On/Off Used to enable and disable return results codes to the DTE. The parameter if valid is written to S-register 14 bit 2. Default: Q0 Q0 Enable the result code. Q1 Disable the result code, OK, ERROR or CONNECT message will not be returned. Vn Result Code Format This command determines the format of the return result code if result codes are enabled (see Qn command). For example, the long form (word format) returns "OK" or short form (numeric format) returns "0". The parameter if valid is written to S-register 14 bit 3. Default: V1 V0 Selects result codes in NUMERIC format. V1 Selects result codes in WORD format. Xn Extended Result Code This command determines which set of responses and calling characteristics are used. This command determines whether the modem recognizes dial tones and busy tones, and what kind of result code should be enabled. When n is 0, 1, or 3, the modem waits for the time specified by S-Register 6 after going off-hook, then dials regardless of the presence or absence of dial tone. Blind dialing is used in some countries where dial tones could very from central office to central office, or for certain PBX’s which generate unique dial tones. The parameter if valid is written to S-register 22 bits 6, 5, and 4. Default: X4 X0 The modem does not recognize dial tone and busy tone. The modem does not wait for dial tone, and blind dialing is enabled. The modem returns a CONNECT result code when a connection is established. X1 The modem does not recognize dial tone and busy tone. The modem does not wait for dial tone, and blind dialing is enabled. The modem returns a CONNECT XXXX result code reflecting the serial port speed when a connection is established. X2 The modem does not recognize busy tones, but waits for dial tone before dialing. If dial tone is not detected within 5 seconds, NO DIALTONE result code is returned. The modem returns CONNECT XXXX result code reflecting the serial port speed when a connection is established. X3 The modem does not recognize dial tone. If a busy tone is detected, BUSY result code is returned. The modem does not wait for dial tone, and blind dialing is enabled. The modem returns CONNECT XXXX result code reflecting the serial port speed when a connection is established. X4 If dial tone is not detected within 5 seconds, NO DIALTONE result code is returned. If a busy signal is detected, BUSY result code is returned. The modem returns CONNECT XXXX result code reflecting the serial port speed when a connection is established. Results Codes for X0 - Messages displayed for X4 X = n. ("x" in column indicates that the message (long or short form will be generated, unless less explicit message indicated by a numeral, is specified) Numeric Alpha (Word) X0 X1 X2 X3 X4 Responses Responses ---------------------------------------------------- 0 OK x x x x x 1 CONNECT x x x x x 2 RING x x x x x 3 NO CARRIER x x x x x 4 ERROR x x x x x 5 CONNECT 1200 1 x x x x 6 NO DIAL TONE 3 3 x x x 7 BUSY 3 3 3 x x 8 NO ANSWER x x x x x 9 CONNECT 600 1 x x x x 10 CONNECT 2400 1 x x x x 11 CONNECT 4800 1 x x x x 12 CONNECT 9600 1 x x x x 13 CONNECT 7200 1 x x x x 14 CONNECT 12000 1 x x x x 15 CONNECT 14400 1 x x x x 16 CONNECT 19200 1 x x x x 17 CONNECT 38400 1 x x x x 18 CONNECT 57600 1 x x x x 19 CONNECT 115200 1 x x x x 22 CONNECT 1 x x x x 75TX/1200RX 23 CONNECT 1 x x x x 1200TX/75RX 24 DELAYED 4 4 4 4 x 32 BLACKLISTED 4 4 4 4 x 33 FAX x x x x x 35 DATA x x x x x 40 CARRIER 300 x x x x x 44 CARRIER 1200/75 x x x x x 45 CARRIER 75/1200 x x x x x 46 CARRIER 1200 x x x x x 47 CARRIER 2400 x x x x x 48 CARRIER 4800 x x x x x 49 CARRIER 7200 x x x x x 50 CARRIER 9600 x x x x x 51 CARRIER 12000 x x x x x 52 CARRIER 14400 x x x x x 53 CARRIER 16800 x x x x x 54 CARRIER 19200 x x x x x 55 CARRIER 21600 x x x x x 56 CARRIER 24000 x x x x x 57 CARRIER 26400 x x x x x 58 CARRIER 28800 x x x x x 59 CONNECT 16800 1 x x x x 61 CONNECT 21600 1 x x x x 62 CONNECT 24000 1 x x x x 63 CONNECT 26400 1 x x x x 64 CONNECT 28800 1 x x x x 66 COMPRESSION: x x x x x CLASS 5 67 COMPRESSION: V.42 x x x x x bis 69 COMPRESSION: NONE x x x x x 76 PROTOCOL: NONE x x x x x 77 PROTOCOL: LAPM x x x x x 80 PROTOCOL: ALT x x x x x 81 PROTOCOL: ALT- x x x x x CELLULAR +F4 +FCERROR x x x x x Data Commands Listed below are the supported commands to control the data modem function, including the modulation options of the IBM 28.8(V.34) / 14.4 Kbps Data/FAX Modems. Bn CCITT or Bell Selection Selects CCITT or Bell modes for 1200 and 300 bps connection. The parameter value, if valid, is written to S-register 27 bit 6. Default: B1 for US/Canada. B0 Selects CCITT V.22 for 1200 bps carrier and V.21 for 300 bps carrier. B1 Selects Bell 212A for 1200 bps carrier and Bell 103 for 300 bps carrier. Fn Select Modulation This command is accepted by the modem, but it performs no function. It is included in this modem for compatibility only. Please refer to the command "Select Modulation" for details on how to achieve the objectives previously handled by the F command. Nn Automode Enable (Automatic Line Speed Detection) This command enables or disables automode detection. The parameter value, if valid is written into S31 bit 1. For more information on Automode, please see the command Select Modulation. Default: N1 N0 Automode detection is disabled (equivalent to setting the +MS subparameter to 0). A subsequent handshake will be conducted according to the contents of S-register 37, or if S-register 37 is zero, according to the most recently sensed DTE speed. N1 Automode detection is enabled (equivalent to setting the +MS subparameter to 1). A subsequent handshake will be conducted according to the contents of S-register 37, or if S-register 37 is zero, starting at 28800 bps V.34. Notes: 1.The Nn and S37=x commands override the +MS command settings. When the N0 or N1 command is issued, the +MS subparameters are updated to reflect the Nn and S37 values (see Select Modulation command and S37). For example:N1S37=10 updates the +MS command subparameters to reflect: +MS=10,1,300,12000 For example:N0S37=10 updates the +MS command subparameters to reflect: +MS=10,0,12000,12000 2.Use of the +MS command is recommended instead of the Nn and S37=x commands. Nn and S37=x commands are supported for compatibility with existing communications software. On Return to On-Line Data Mode This command determines how the modem will enter the on- line data mode. If the modem is in the on-line command mode, it enters the on-line data mode, and if operating at speeds greater than 1200 bps, the modem can be instructed to retrain on its way to the connect state. If the modem is in the off-line command mode (no connection), ERROR is reported. O0 Enters on-line data mode without a retrain in V.32bis, V32, or V.22bis. Handling is determined by the call establishment task. Generally, if a connection exists, this command hooks the DTE back to the remote modem after an escape(+++). O1 Instructs the modem to return to the on-line state after initiating a retrain when operating in V.32bis, V.32 or V.22bis. Poor line quality or noise on the line may cause the local modem to go out of synchronization with the remote modem. When the mode is out of synchronization, random data may be displayed on the screen. The O1 command forces the modem to initiate a retrain to get synchronization with the remote modem and return an appropriate CONNECT result code. The O1 command is valid when the modem is connected in direct/normal mode on V.22bis carrier. Wn Negotiation Progress (Connect Message) Control This command Controls the format of CONNECT messages. The parameter if valid, is written to S-register 31 bits 2 and 3. The Wn command can be overridden by S- register 95. Default: W0 W0 Reports DTE rate only (Serial port speed). W1 Reports DCE rate (modem to modem line speed), Error correction Protocol, and DTE rate (Serial port speed). W2 Reports DCE rate (modem to modem line speed). %En Auto-Retrain control This command disables or enables the auto-retrain feature of the modem. When %E1 is set the modem automatically monitors the line quality and initiates a retrain sequence for more reliable connection if the line quality is too poor to continue communication. The parameter if valid is written to S-register 41 bits 2 and 6. Default: %E2 %E0 Disables line quality monitor and auto- retrain. %E1 Enables line quality monitor and auto- retrain. %E2 Enables line quality monitor and fallback / fall forward. %L Line Signal Level This command returns a value indicating the received signal level at the data pump, not the telephone connector. For example, 009 = -9 dBm, 043 = -43 dBm, etc. %Q Line Signal Quality This command returns a value indicating the high order byte of the EQM value. Based on the EQM value, retrain or fallback / fall forward may be initiated if enabled by %E1 or %E2. The modem must be connected otherwise ERROR will be returned. &Gn Select Guard Tone This command generates the guard tone selected by this command according to the parameter supplied (DSPK modulation modes only). Guard tones are always disabled in the USA. The parameter if valid is written to S- register 23 bits 6 and 7. Default: &G0 &G0 Disable guard tone &G1 Disable guard tone &G2 Use 1800Hz guard tone &Qn Communication Mode Selection (Sync/Async Mode) An extension of the &M command used to control the connection modes permitted. Used in conjunction with S36 and S48. The parameter if valid is written to S- register 27 bits 3, 1, and 0. Note: When the &Q0 to &Q4 command is issued to select the mode, the subsequent connect message will report the DCE speed regardless of the W command and S-Register 95 settings. Default: &Q5 &Q0 Selects the Direct asynchronous operation. The value 000b is written to S-register 27 bits 3,1, and 0. See &M0. &Q1 Not supported &Q2 Not supported &Q3 Not supported &Q4 Select AutoSync Operation. AutoSync operation, when used in conjunction with Hayes Synchronous Interface (HSI) capability in the DTE, provides synchronous communication capability from an asynchronous terminal. The value 100b is written to S- register 27 bits 3,1, and 0. Starting AutoSync: Set S-registers 19, 20, and 25 to the desired values before selecting AutoSync operation with &Q4. After the CONNECT message is issued, the modem waits the period of time specified by S-register 25 before examining DTR. If DTR is on, the modem enters the synchronous operating state: if it is off, the modem terminates the line connection and returns to the asynchronous state. Stopping AutoSync: AutoSync operation is stopped upon loss of carrier or the on-to-off transition of DTR. Loss of carrier will cause the modem to return to asynchronous command state. An on-to-off transition of DTR will cause the modem to return to the asynchronous command state and either not terminate the line connection (&D1 active), or terminate the line connection (any other &Dn command active). &Q5 Selects error correction mode. In this mode error correction link is enabled. The modem negotiates with the remote modem according to S36, S46, and S48 settings. The serial port speed can be greater than modem carrier speed, in which case, flow control in the sending direction might be required. &Q6 Selects Normal mode connection with speed buffering. In this mode, the DTE speed can be greater than modem carrier speed. Flow control in both directions may be required to maintain reliable (error corrected) connections. +MS Select Modulation This command is used to select the modulation that the modem is to use. In addition, it may optionally select or deselect automode operation. It may also optionally be used to specify the highest and lowest acceptable connect speeds. The command format for this command is: +MS= [,][,][,MAX_R ATE>] Parameters shown above surrounded by brackets are optional. The defaults for this command are: Modulation V.34 Automode Enabled MIN_RATE 300 bps MAX_RATE 28800 bps Notes: 1.For 14400 bps and lower speeds, the Nn command and S- Register 37 can alternatively be used, in which case the +MS subparameters will be modified to reflect the Nn and S37=x settings. Use of the Nn and S37=x commands is not recommended, but is provided for compatibility with existing communication software (S37 is not updated by the +MS command). 2.Subparameters not entered (enter a comma only or to skip the last subparameter) remain at their current values. The options for the modulation parameters are: Parameter 1 - Modulation. Modulation is a decimal number used to specify the preferred modulation (automode enabled), or the modulation (automode disabled) to use in originating or answering a call. The options for this parameter are: Default = 11 Modulatio Standard DCE Rates n Used 0 V.21 300 1 V.22 1200 2 V.22bis 1200, 2400 3 V.23 1200 9 V.32 9600 or 4800 10 V.32bis 14400, 12000, 9600, 7200, 4800 11 V.34 28800, 26400, 24000, 21600, 19200, 16800, 14400, 12000, 9600, 7200, 4800, or 2400 64 Bell 103 300 69 Bell 212 1200 74 V.FC 28800, 26400, 24000, 21600, 19200, 16800, or 14400 Note: For V.23, the originating and answering modems communicate at different speeds. The originating modem transmits at 75bps and receives at 1200bps. The answering modem transmits at 1200bps and receives at 75bps. The rate is always specified as 1200 bps. The modem can switch to another modulation (Automode), subject to the following conditions: o Switching from certain modes to other modes may not be possible. For example, there is no standard technique for switching from the Bell 103 standard to V.23. o Automode may be disabled, preventing the switching (see Automode below). o The modem may restrict the range of acceptable modulations by specifying the highest and lowest acceptable rates (see Min_rate and Max_rate below). Parameter 2 - Automode. Automode is an optional number that enables or disables automatic modulation negotiation using V.8 or V.32 bis Annex A The options are as follows: Default = 1 Modifier Usage 0 Automode disabled 1 Automode enabled using V.8 or V.32 Annex A The default Automode value is dependent upon the Automode technique defined for the specified modulation. For certain specified modulations, there is no automatic modulation defined, e.g. Bell 212 ( =69). Automode Behavior Automode behaves differently depending upon the value of the Automode setting, the modulation selected and the minimum and maximum BPS rates programmed. The behavior is: o For Automode = 0, (Automode disabled, i.e., fixed modulation) * If the specified value of is within the range of rates supported by the modulation selected by , then the bit rate used is the rate specified by . For example +MS=9,0,1200,4800 selects V.32 modulation with a 4800 bps fixed rate. * If the specified value of is greater than the highest bit rate supported by the specified , then the starting bit rate selected is the highest rate supported by . For example +MS=9,0,2400,14400 selects V.32 modulation at 9600 bps initial bit rate. Note that the actual connect rate may drop to 4800 bps if connection is not achieved at 9600 bps. * In order to completely specify that only one connection speed is acceptable (emulate the N0S37=x commands), you should set both and to the (same) requested value, and to be the modulation for that speed. For example +MS=11,0,16800,16800 selects V.34 modulation at 16800 bps fixed mode (no comparable S37 command). For example +MS=9,0,12000,12000 selects V.32bis modulation at 12000 bps fixed mode (same as N0S37=10). o For Automode = 1, (Automode enabled, i.e., automatically selected speed and modulation) The modem connects at the highest possible rate in accordance with V.8, or V.32 bis ANNEX A if V.8 is not supported by the remote modem. * If is specified as greater than the highest bit rate supported by , then the modem will use its automode capability to step down from the highest valid bit rate. For example +MS=10,1,1200,24000 selects automoding down from V.32 bis 14400 * To emulate issuance of the N1S37=x command sequence, specify the modulation and the rate to start automoding down from using and respectively. Set to 300 to allow automoding all the way down to the slowest possible rate (V.21, 300 bps). For example +MS=11,1,300,16800 selects automoding starting at V.34 16800 bps (no comparable S37 command) For example +MS=9,1,300,12000 selects automoding starting at V.32bis modulation at 12000 bps (same as N1S37=10). Parameter 3 - . is an optional number used to specify the lowest rate at which the modem may connect. The value is a decimal number in units of bits per second. The default for this value is 300 bps. Parameter 4 - . is an optional number used to specify the highest rate at which the modem may connect. The value is a decimal number in units of bits per second. The default is 28800 bps. Inquiry Responses: The modem responds to two different inquiry formats to return information about its settings to the host. Those two responses are: o Current Settings: This is the result of issuing an +MS? command. The modem will respond with its current settings. For example: Command: +MS? Modem Response: +MS: ,,, MAX_RATE> For example: +MS: 11,1,300,28800 (shows default values) o Supported Settings: This response is issued as the result of issuing an +MS=? command. The modem will respond with all of its supported options. For example: Command: +MS=? Modem Response: +MS: ,,< List of supported MIN_RATE values>, List of supported MAX_RATE values> For example: +MS: (0,1,2,3,9,10,11,64,69,74),(0,1),(3 00-28800),(300-28800) MNP Operation Microcom Networking Protocol (MNP*) is a protocol developed by Microcom for full-duplex, error-free communications. This protocol detects and corrects errors that can result from telephone line noise and other signal distortions. There are several classes of MNP operation (also referred to as service classes). Class 5, for instance, maximizes data transfer rate and provides compression that can significantly increase data throughput. \An Select Maximum MNP Block Size This command sets the maximum allowable block size when operating an MNP error corrected link. The minimum block size is not restricted. In general, the better the line quality, the larger the blocks. The parameter value is written to S-register 40 bits 6 and 7. Default: \A2 \A0 64 Characters \A1 128 Characters \A2 192 Characters \A3 256 Characters \Bn Transmit Break This command causes the modem to transmit a BREAK whose length is specified by the n parameter in units of 100 milliseconds. In reliable (error corrected) mode, the modem will signal a BREAK through the active error correction protocol. The command works in conjunction with the \Kn command. Default: 3 (300 milliseconds) Range: 1 - 9 \Kn Break Control This command determines how the modem processes a BREAK received from the DTE (via the \B command), or the remote modem. The resulting behavior depends on the state of the modem and is defined below. The parameter value, if valid, is written to S40 bits 3, 4, and 5. 1.The modem receives a break from the DTE when the modem is operating in data transfer mode: Default: \K5 \K0 Enter on-line command mode, no break sent to the remote modem. \K1 Clear data buffers and send break to remote modem. \K2 Same as \K0. \K3 Send break to remote modem immediately. \K4 Same as \K0. \K5 Send break to remote modem in sequence with transmitted data. 2.The modem is in the on-line command state (waiting for commands) during a data connection, and the BREAK is received in order to send a break to the remote modem: Default: \K5 \K0 Clear data buffers and send break to remote modem. \K1 Clear data buffers and send break to remote modem. \K2 Send break to remote modem immediately. \K3 Send break to remote modem immediately. \K4 Send break to remote modem in sequence with data. \K5 Send break to remote modem in sequence with data. 3.A break is received from a remote modem during a non- error corrected connection: Default: \K5 \K0 Clears data buffers and sends break to the DTE. \K1 Clears data buffers and sends break to the DTE. \K2 Send a break immediately to DTE. \K3 Send a break immediately to DTE. \K4 Send a break in sequence with received data to DTE. \K5 Send a break in sequence with received data to DTE. \Nn Protocol Negotiation Selection This command controls the preferred error correction mode to be negotiated in a data connection. See &Qn, S36, and S48. Default: \N3 \N0 Selects Normal Speed buffered mode. Disables Error Correction and forces &Q6 \N1 Selects Direct mode. Serial Interface selected without buffer. Equivalent to &M0 and &Q0 \N2 Selects reliable (error corrected) mode. The modem attempts LAPM reliable link connection, and then an MNP connection. If failed the modem disconnects the line. Forces &Q5, S36=4, and S48=7. \N3 Selects auto reliable (error corrected) mode. The modem attempts LAPM reliable link connection, and then an MNP connection. If failed the modem switches to normal mode connection. Forces &Q5, S36=7, and S48=7. \N4 Selects LAPM error correction mode. The modem attempts LAPM reliable (error corrected) link connection. If failed the modem disconnects the line. Forces &Q5 and S48=0. \N5 Selects MNP error correction mode. The modem attempts LAPM reliable (error corrected) link connection. If failed the modem disconnects the line. Forces &Q5, S36=4, and S48=128. Data Compression The communications link between the serial port and the modem controller needs to provide full duplex character data at a rate fast enough to accommodate the transfer of synchronous T.30 phase C data and V.42bis compressed data. The data rate should be 4 times faster than the maximum expected communication rate to accommodate V.42bis compression rates. For example, 57,600 bps is the minimum rate needed to support V.42bis at 14,400 bps. 19,200 bps is sufficient to support facsimile signaling at up to 14,400 bps. With flow control, changing the DTE-DCE communication link data rate during facsimile operation is not necessary. %Cn Enable/Disable Data Compression Controls the data compression algorithm to be used. The parameter if valid is written to S-register 41 bits 0 and 1. Default: %C3 %C0 Disables data compression. %C1 Enables MNP 5 data negotiation compression. %C2 Enables V.42 bis data compression. %C3 Enables MNP 5 and V.42 bis data compression. MNP 10 Operation :En Compromise Equalizer Setting By default, the V.32 compromise equalizer is turned on. However, with some cellular lines, connections may be more reliable with the compromise equalizer turned off. The parameter if valid is written to S-register 201 bit 5. Default: :E1 :E0 Disable equalizer. :E1 Enable equalizer. *Hn Link Negotiation Speed This command controls the initial connection speed for MNP 10 link negotiations (See S-register 40). The parameter value if valid, is written to S-register 28 bits 6 and 7. Default: *H0 *H0 Link negotiation at highest speed supported. *H1 Link negotiation at 1200 bps (used primarily for establishing cellular connections). *H2 Link negotiation at 4800 bps (used to establish and MNP 10 connection on less than average quality phone lines). -Kn MNP Extended Services This command enables or disables conversion of a V.42 LAPM connection to an MNP 10 connection. The parameter if valid is written to S-register 40 bits 0 and 1. Default: -K1 -K0 Disable conversion. -K1 Enable conversion. -K2 Enable conversion, except during V.42 LAPM answer detection. )Mn Cellular Power Level Adjustment This command enables or disables the automatic transmit power level adjustment during MNP 10 link negotiation. The @Mn command sets the initial modem transmit level. The parameter if valid is written to S-register 40 bit 2. Default: )M0 )M0 Disable power level adjustment. Transmit power level adjustment is allowed if cellular operation is requested by the remote modem. )M1 Enable power level adjustment. Initial levels are determined by @Mn command, but after connection, the levels are determined by the modem. Do not use )M1 with *H2. )M2 Enables transmit power level adjustment during negotiation. After connection, the power level remains fixed. @Mn Initial Cellular Power Level Setting Sets the initial transmit power level for upshift at connect until line conditions can be determined. The parameter if valid is written to S-register 201 bits 0- 4. Default: @M0 @M0 -26 dBm. @M1 -30 dBm. @M2 to @M10 -10 dBm. @M11 -11 dBm. @M12 -12 dBm. .. .. @M30 -30 dBm. @M31 -31 dBm. -Qn Enable Fallback to V.22bis/V.22 This command enables or disables fallback from MNP 10 to V.22bis/V.22. The parameter if valid is written to S- register 41 bit 7. Default: -Q1 -Q0 Disable fallback to 2400 bps (V.22bis) and 1200 bps (V.22). -Q1 Enable fallback to 2400 bps (V.22bis) and 1200 bps (V.22). Modem Test and Diagnostic Commands &Tn Test Mode For these tests, direct mode connection should be selected. Error correction and data compression must be turned off. Default: &T5 &T0 Terminates any test in progress. This command is required to terminates the test if test timer (S18) is not running. If the test is in progress in on-line state, the escape sequence is required before this command. &T1 Initiates local analog loopback test (V.54 loop 3). This test starts after an appropriate CONNECT message. The characters received from the DTE are modulated, demodulated and echoed back to the DTE. This test works in a stand alone modem without a remote modem. &T2 Returns ERROR &T3 Initiates local digital loopback test (V.54 loop 2). The characters received from the remote modem are looped back to the remote modem by the local modem. Before issuing this command at the local modem, &T4 setting must be active at the remote modem. This test starts after the modem returns an OK result code. &T4 Allows the modem to accept a request from a remote modem for a remote digital loopback test and a local digital loopback test. The modem must be in the on-line state to accept the request. This setting is default. &T5 Disable the modem to accept a request from a remote modem for a remote digital loopback test and a local digital loopback test. &T6 Requests a remote digital loopback (V.54 loop 2) without self test. If no connection exists first, ERROR is returned. &T7 Requests a remote digital loopback (V.54 loop 2) with self test. If no connection exists first, ERROR is returned. &T8 Initiates local analog loopback (V.54 loop 3) with self-test. This test starts after the modem returns an OK result. This test works similarly to &T1, but the modem sends an alternating zeros and ones (010101..) pattern and continuously verifies the loopback data. The modem increments its error counter each time an error is detected. At the end of the test, the modem returns a three digit error count to the DTE like 000 as no error. This test works on a stand alone modem without a remote modem. FAX COMMANDS The modem supports ITU-T Group 3, and Class 1 and 2 fax command sets. We suggest that you use your fax software to issue all the necessary fax commands to your modem. Programmers should refer to the ITU-T specifications. S REGISTERS Located within the modem are some common registers which control the modem’s operation, dialing parameters, answering capability, etc. These registers have default values set at power on reset. Listed below are the register definitions and their default values. Some "S" register values are not changeable by the user. Note: 1. Because of improvements to the usability of this product, the default value for the S-Registers specified in this manual might differ from the actual value of your modem. See "Reading a Register Value" to determine the actual default value. 2. Communication software programs often have default values of their own that are written to the modem when the modem is brought on-line or connected. Refer to the documentation that came with the communication software product you are using to determine how to view and change these default values. Reading a Register Value To read the current value of a register, you should be in the command mode of your communications software. Typing the following: ATSn? < Enter> where n is a register number, will cause the modem to respond with the decimal value of the register in 3- digit form. This will be followed by OK or 0. To read values from more than one register, type the following from the command mode. ATSn? Sn? < Enter> To read the register values of S0 and S1, type the following: AT S0? S1? < Enter> The modem will display the first register value, a carriage return, the next register value, a carriage return, and OK or 0. Changing A Register Value To change a register value, use the Sn command (Sn=x ), where n is a register number and x is the new value you want to assign to the register. Typing the following: AT S0=3 < Enter> will have the modem automatically answer incoming calls after the third ring. The changed values remain in effect until the modem is reset, or power is cycled off and on. The modem then returns to its default settings. Accessing A Register Repeatedly The modem automatically places a pointer at the last register whose value was read or changed. The pointer provides a fast way of displaying or changing register values. Typing the following: ATS0? < Enter> reads the value of S-Register 0. The modem responds displaying the value of register S0 and places a pointer at that register automatically. Typing the following: AT=0 changes the value in S-Register 0 to 0. Neither the S command nor the register number has to be specified; the pointer handles this task. To read the S0 value, type the following: AT? < Enter> The pointer remains set at the last register accessed until the S command is used to read or change the value of a different register. The pointer is then set to the register whose value is displayed or changed. How to Set Bit-Mapped Registers To set or change bit-mapped registers requires a sound working knowledge of binary notation. Bit-mapped S- Register values are calculated as follows. Each bit (0- 7) has a corresponding decimal value as shown below. If the bit is ON, it has that corresponding value; if the bit is OFF, its value is zero. Bit Decimal 0 1 1 2 2 4 3 8 4 16 5 32 6 64 7 128 S Register Commands Sn? Read an S Register With this command the S-Register specified by n can be read. For example, S36? displays the contents of S- Register 36. Range: 0 - 201 Sn=x Write an S Register Value With this command the contents of the S-Register specified by n will be updated to the value of x. For example, S48=128 sets S register 48 to the value 128. Range: n = 0 - 201 Range: x = 0 - 255 Sn Select a Specific S Register This command selects the specified S register Range: 0 - 201 =x Write to Currently Selected S Register This command writes to the S register currently selected by one of the previous commands. Range: 0 - 255 ? Read Currently Selected S Register This command reads from the S register currently selected by one of the previous commands. S Register Definitions S0 Auto Answer Number of rings until auto-answer. A value of 0 indicates auto-answer is disabled. Default: 0 Range: 0-255 rings Value may be stored in user profiles with the &Wn command. S1 Ring Counter This register contains the number of rings detected by the modem. If there is no RING for 8 seconds, this register is cleared to 0. Default: 0 Range: 0-255 rings S2 Escape Character This register defines an ASCII decimal value of the escape code. The default setting is an ASCII '+', the escape sequence is “+++”. A value over 127 disables the escape sequence. Default: 43, ASCII '+' Range: 0-255, ASCII decimal Value may be stored in user profiles with the &Wn command. S3 Carriage Return Character This register defines an ASCII decimal value of the Carriage Return character which is used as the terminator of both the command line and result code. The value of this register is not stored in the non- volatile memory. It is always set to the default setting at power up. Default: 13 (Carriage Return) Range: 0-127, ASCII decimal S4 Line Feed Character This register defines an ASCII decimal value of the Line Feed character which is used as the terminator of a result code preceded by the carriage return when WORD format for result code is selected. The value of this register is not stored in non-volatile memory. It always returns to the default setting at power up. Default: 10 (Line Feed) Range: 0-127, ASCII decimal S5 Backspace Character This register defines an ASCII decimal value of the Backspace character which is used to edit a command line. When echo back is enabled (E1) and the system sends an Backspace character at command state, the modem sends back the 3 characters of Backspace, Space, and Backspace in a row. The value of this register is not stored in the non-volatile memory, it always returns to the default setting at power up. Default: 8 (Backspace) Range: 0-127 ASCII decimal S6 Delay Time for Blind Dialing This register defines the length of time the modem waits before beginning to dial after going off-hook when blind dialing. The modem always waits at least 2 seconds, even if register S6 is set to less than 2 seconds. Blind dialing is enabled by X0,1,3 setting. When X2 or X4 setting is active, this register has no meaning. Default: 2 Range: 2-255 seconds Value may be stored in user profiles with the &Wn command. S7 Delay Time for Carrier Detect following Dialing This register defines the following three delay times. 1. The delay time that the modem will wait for carrier after dialing and before hanging up. If the modem does not detect the carrier within the time, the modem disconnects the line and returns the "NO CARRIER" result code. 2. The delay time that the modem will wait for dial tone after the modem detects a W parameter in the dial string. If the modem does not detect dial tone after the time specified in this register, the modem will disconnect the line and returns a "NO DIALTONE" result code. 3. The delay time that the modem will wait for silence after the modem detects a @ in the dial string. If the modem does not detect the silence by the time specified in this register, the modem will disconnect the line and return a "NO ANSWER" result code. Default: 50 seconds Range: 1-255 seconds Value may be stored in user profiles with the &Wn command. S8 Pause Time for "," within Dial String This register defines the length of time the modem pauses when the modem detects "," in the dial string. Default: 2 Range: 0-255 seconds Value may be stored in user profiles with the &Wn command. S9 Carrier Detect Response Time This register defines the length of time that the carrier signal must be present before the modem recognizes it as a carrier. As this time is increased, it prevents the modem from recognizing noise on the line as a carrier. Default: 6 (0.6 seconds) Range: 1-255 tenths of a second Value may be stored in user profiles with the &Wn command. S10 Carrier Loss Disconnect Delay This register defines the length of time the modem waits before hanging up after a loss of carrier. This delay time disables the modem from hanging up on a temporary loss of carrier. A loss of carrier which lasts over the time of S10 minus S9 causes the modem to disconnect the line. Therefore values of S10 must be greater than one of S9, otherwise temporary loss of carrier always causes a hang up. When S10 is set to 255, the modem functions as if the carrier is always present. Default: 14 (1.4 seconds) Range: 1-255 tenths of a second Value may be stored in user profiles with the &Wn command. S11 DTMF Tone Duration This register defines the duration of tones for DTMF dialing. Default: 95 milliseconds Range: 50-255 milliseconds Value may be stored in user profiles with the &Wn command. S12 Escape Code Guard Time This register defines the length of time for Escape Code Guard Time. To detect the escape sequence, no user data must be present for the guard time immediately after and before an escape sequence, and also pause time between escape codes must be less than the guard time. + + + pause TS pause t1 pause t2 pause TE TS, TE > S12 value t1, t2 < S12 value Default: 50 (1 second) Range: 0-255 fiftieths of a second Value may be stored in user profiles with the &Wn command. S13 Reserved S14 General Bit Mapped Options Default: 138, (10001010b) Bit 0 - This bit is ignored. Bit 1 - Command echo (En) 0 = Disabled (E0) 1 = Enabled (E1) (default) Bit 2 - Quiet mode (Qn) 0 = Send result codes (Q0) (default) 1 = Do not send result codes (Q1) Bit 3 - Result codes (Vn) 0 = Numeric (V0) 1 = Word (V1) (default) Bit 4 - Reserved Bit 5 - Tone (T)/Pulse (P) 0 = Tone (T) (default) 1 = Pulse (P) Bit 6 - Reserved Bit 7 - Originate/Answer 0 = Answer 1 = Originate (default) Value may be stored in user profiles with the &Wn command. S15 Reserved S16 Diagnostic Status Register Indicates the test in progress status. Default: 0 Bit 0 - Local analog loopback (&T1) 0 = Test is not in progress 1 = Test is in progress Bit 1 - Not Used Bit 2 - Local digital loopback (&T3) 0 = Test is not in progress 1 = Test is in progress Bit 3 - Remote digital loopback status (&T4) 0 = Test is not in progress 1 = Test is in progress Bit 4 - Remote digital loopback (&T6) 0 = Test is not in progress 1 = Test requested Bit 5 - Remote digital loopback with self test (&T7) 0 = Test is not in progress 1 = Test is in progress Bit 6 - Local analog loopback with self test (&T8) 0 = Test is not in progress 1 = Test is in progress Bit 7 Not Used. S17 Reserved S18 Test Timer This register defines the length of time a test will execute. The modem conducts a diagnostics test for the amount of the time specified by S18 and automatically terminates the test and returns to command state after an OK result code. When default value 0 is set, the modem continues the test until &T0 or H command is issued. Default: 0 Range: 0-255 seconds Value may be stored in user profiles with the &Wn command. S19 AutoSync Bit Mapped Options The S19 register controls some of the operation of the AutoSync capability of this modem. For more information on AutoSync, please refer to the command "Communication Mode Selection (Sync/Async Mode)". S19 must be set to the desired value before &Q4 is issued. Default: 0 Bit 0 - Reserved Bit 1 - BSC/HDLC Format Select 0 = Bisync Format Select (default) 1 = HDLC Format Select Bit 2 - Address Detection Enabled/Disabled 0 = Disabled (default) 1 = Enabled Bit 3 - NRZI/NZI Coding Selection 0 = NRZI (default) 1 = NZI Bit 4 - Idle Indicator Select 0 = Mark Idle (default) 1 = Flag/Sync Idle Bits 5-7 - Reserved S20 AutoSync HDLC Address or BSC Sync Character The S20 register defines either the SDLC/HDLC address (if S19 bit 0 is 1) or the BSC Sync character (if S19 bit 0 is 0). This bit is active only if the modem is operating in AutoSync mode. Both registers S19 and S20 must be set before attempting AutoSync operation. For more information on AutoSync, please refer to the command "Communication Mode Selection (Sync/Async Mode)". Default: 0 Range: 0-255 Value may be stored in user profiles with the &Wn command. S21 V.24/General Bit Mapped Options/Status Indicates the status of command options Default: 4, ('00000100'b) Bit 0 - Set by &Jn command but ignored otherwise. 0 = &J0 (Default) 1 = &J1 Bit 1 - Reserved Bit 2 - CTS Behavior (Set by &Rn) 0 = CTS tracks RTS (&R0) 1 = CTS is always on (&R1) (Default) Bit 3,4 - DTR Behavior (Set by &Dn) 00 = &D0 Selected (Default) 01 = &D1 Selected 10 = &D2 Selected 11 = &D3 Selected Bit 5 - RLSD (DCD) behavior (&Cn) 0 = &C0 Selected (Default) 1 = &C1 Selected Bit 6 - DSR Behavior (&Sn) 0 = &S0 Selected (Default) 1 = &S1 Selected Bit 7 - Long Space (Yn) 0 = Y0 (Default) 1 = Y1 Value may be stored in user profiles with the &Wn command. S22 Speaker Control/Results Status Indicates the status of command options Default: 117, ('01110101'b) Bit 0,1 - Speaker Volume (Ln) 00 = Off (L0) 01 = Low (L1) 10 = Medium (L2) (Default) 11 = High (L3) Bit 2,3 - Speaker Control (Mn) 00 = Disabled (M0) 01 = Off on Carrier (M1) (Default) 10 = Always on (M2) 11 = On during handshake (M3) Bit 4-6 - Limit Result Codes (Xn) 000 = X0 100 = X1 101 = X2 110 = X3 111 = X4 Bit 7 - Reserved Value may be stored in user profiles with the &Wn command. S23 General Bit Mapped Options Status Default: (54d), ('00110110'b) Bit 0 - Grant RDL 0 = RDL is not permitted (&T5) (Default) 1 = RDL is permitted (&T4) Bit 1,2,3 - Local DTE Rate 000 = 300 bps 001 = 600 bps 010 = 1200 bps 011 = 2400 bps (Default) 100 = 4800 bps 101 = 9600 bps 110 = 19200 bps 111 = 38400 bps or higher Bit 4,5 - Parity Option 00 = even 01 = not used 10 = odd 11 = none (Default) Bit 6,7 - Guard Tone (&Gn) 00 = None (&G0)(Default) 01 = None (&G1) 10 = 1800 Hz (&G2) Value may be stored in user profiles with the &Wn command. S24 Sleep Inactivity Timer This register is in units of seconds. If the value programmed into this register is zero, then this feature is disabled. The timer is reset on any DTE activity. If the timer expires, then the modem will go into sleep mode. If S24 is set to zero, DTE inactivity will not cause the modem to enter sleep mode. Default: 0 Range: 0-255 seconds Value may be stored in user profiles with the &Wn command. S25 DTR Detection Delay This register defines the length of time that the modem will ignore a DTR drop before hanging up. Default: 5 (.05 second) Range: 0-255 seconds S26 RTS to CTS Delay This register is used to set the time, in hundredths of a second, that the modem will wait before it sets the CTS signal active after it detects an OFF-to-ON transition on the RTS signal when the &R0 attribute is active. Pertains to synchronous operation only. Please see the command "RTS/CTS (Hardware) Flow Control" for further information. Default: 1 ( 0.01 second) Range: 0-255 hundredths of a second S27 Mode Selection Indicates the status of command options. Default: 9, ('00001001'b) Bit 3,1,0 - 000 &M0 or &Q0 001 = &Q1 010 = &Q2 011 = &Q3 100 = &Q4 101 = &Q5 (Default) 110 = &Q6 Bit 2 - Leased Line Control (leased line not supported) 0 = PSTN Link (&L0) (Default) 1 = Leased Line (&L1) - not supported Bit 4,5 - Internal Clock Select 0 = Internal Clock (&X0) (Default) 1 = External Clock (&X1) 2 = Slave (&X2) Bit 6 - Bell/CCITT Select 0 = CCITT Mode (B0) (Default) 1 = Bell Mode (B1) Bit 7 - Reserved Value may be stored in user profiles with the &Wn command. S28 Mode Selection II This register stores the settings for the MNP-10 negotiation speed as well as the parameters to be used for dialing when the modem is set up in pulse mode instead of its default tone dialing. Default: 0 Bit 0,1 - Reserved Bit 2 - Reserved (Always set to '0') Bit 3,4 - Pulse Dialing Make/Break ratio 0 = 39/61; 10 pulses per second (Default) 1 = 33/67; 10 pulses per second 2 = 39/61; 20 pulses per second 3 = 33/67; 20 pulses per second Bit 5 - Reserved Bit 6,7 - MNP Link Negotiation Speed (*Hn) 0 = Link negotiation at highest speed (*H0) (Default) 1 = Link negotiation at 1200 bps (*H1) 2 = Link negotiation at 4800 bps (*H2) Value may be stored in user profiles with the &Wn command. S29 Flash Modifier This register gives the time in units of 10ms the modem goes on-hook for the flash modifier in the dial string. It can be limited as it is a country dependent parameter. Default: 0 (Disabled) Range: 0-255 (units of 10 milliseconds) S30 Auto Disconnect Inactivity Timer This register is used to set the amount of time, in ten second units, that the modem will stay on-line before disconnecting its link when no data is being sent or received. When the modem is in an error-correction mode (either MNP or V.42bis), the timer will be reset whenever any data is received or transmitted. When the modem is connected in any other mode, then any data transmitted will reset the timer. This timer is inactive when the modem is operating in synchronous mode. Default: 0 (Disabled) Range: 0-255 (units of 10 seconds) S31 Bit Mapped Options Status Bit 1 is used to indicate whether or not the modem can connect with automatic line speed detection, allowing the modem to change the line speed if necessary. Bits 2 and 3 indicate the connection messages that the modem will report to the host when an error correcting link is being established. Please see "Protocol Negotiation Selection" , and "Negotiation Progress (Connect Message) Control",for more information. Default: 2, ('00000010'b) Bit 0 - Reserved Bit 1 - Automatic Line Speed Detection 0 = Auto Line Speed Disabled (N0) 1 = Auto Line Speed Enabled (N1) (Default) Bit 2,3 - Error Correction Progress Message Reporting 00 = Report DTE speed only (W0) (Default) 01 = Full Report (W1) 10 = Report DCE speed only (W2) Bit 4-7 - Reserved Value may be stored in user profiles with the &Wn command. S32 XON Character This register defines the XON Character used when the modem is using XON/XOFF flow control. Default: 17 ('00010001'b) Range: 0-255 (ASCII) S33 XOFF Character This register defines the XOFF Character used when the modem is using XON/XOFF flow control Default: 19 ('00010011'b) Range: 0-255 (ASCII) S34 - S35 Reserved S36 LAPM Failure Control This register controls the way in which the modem will behave upon a LAPM (V.42bis) error correcting link failure. These fall back behaviors will be executed immediately if the S48 register is set to 128 ('10000000'b). Default: 7 ('00000111'b) Bits 0-2 - LAPM Failure Behavior 000 = Disconnect. 001 = Stay on-line and establish a Direct connection. 010 = Reserved 011 = Stay on-line and establish a Normal connection. 100 = Attempt MNP connection. If the MNP connection fails, disconnect. 101 = Attempt MNP connection. If the MNP connection fails, establish a Direct connection. 110 = Reserved 111 = Attempt MNP connection. If the MNP connection fails, establish a Normal connection. Bits 3-7 - Reserved Value may be stored in user profiles with the &Wn command. S37 Desired Line Connection Speed This register specifies the desired line connection speed. Default: 0 Bit 4-0 - Desired Line Connection Speed. If an invalid number is entered, the number is accepted into the register, but S37 will act as if the default value has been entered. 0000 = Attempt Automode connection (Default). If N0 is active, connection is attempted at the most recently sensed DTE speed (+MS command settings are updated to the appropriate values). If N1 is active, connection is attempted at the highest possible speed (+MS settings are updated to 11,1,300,28800 to reflect V.34, automode, 300 bps minimum speed, and 28800 bps maximum speed) 0001 = Attempt to connect at 300 bps. 0010 = Attempt to connect at 300 bps. 0011 = Attempt to connect at 300 bps. 0100 = Reserved. 0101 = Attempt to connect at 1200 bps/V.22. 0110 = Attempt to connect at 2400 bps/V.22bis. 0111 = Attempt to connect at V.23. 1000 = Attempt to connect at 4800 bps/V.32-V.32bis. 1001 = Attempt to connect at 9600 bps/V.32-V.32bis. 1010 = Attempt to connect at 12000 bps/V.32bis. 1011 = Attempt to connect at 14400 bps/V.32bis. 1100 = Attempt to connect at 7200 bps/V.32bis. 1101 = Reserved. 1110 = Reserved. 1111 = Reserved. Bit 5-7 - Reserved. Value may be stored in user profiles with the &Wn command. Notes: 1. When the Nn command is issued or the S37 register value is modified, the +MS command subparameters are updated to reflect the speed and modulation specified by S37 (see Select Modulation command). For example: If N0 command is active, S37=10 updates the +MS command subparameters to reflect +MS=10,1,300,12000 If N1 command is active, S37=10 updates the +MS command subparameters to reflect +MS=10,0,12000,12000 2. S-Register 37 is not updated by the +MS command. 3. Use of the +MS command is recommended instead of Nn and S37=x commands. Nn and S37=x commands are supported for compatibility with existing communication software. S38 Forced Hang-up Delay This register contains the delay, in seconds, between the time that the modem is issued a H disconnect command and the time that the modem executes the disconnect operation. This register is active only if a modem is in error correcting mode. Default: 20, ('00010100'b) Range: 0-255 seconds S39 Flow Control This register controls the way in which the modem controls flow between itself and the remote modem. Default: 3, ('00000011'b) Bits 0-2 - Flow Control 000 = None 011 = RTS/CTS (&K3) (Default) 100 = XON/XOFF (&K4) 101 = Transparent XON (&K5) 110 = Both RTS/CTS and XON/XOFF(&K6) Bits 3-7 - Reserved Value may be stored in user profiles with the &Wn command. S40 MNP Error Correction Controls Default: 105, ('01101001'b) Bits 0-1 - MNP Extended Service 00 = Disable extended services (-K0) 01 = Enable extended services (-K1) (Default) 11 = Enable extended services (-K2) Bit 2 - MNP10 Power Level Adjustment for Cellular Use 0 = Auto-Adjustment ()M0) (Default) 1 = Force Adjustment ()M1) Bit 3,4,5 - Break Handling 000 = (\K0) 001 = (\K1) 010 = (\K2) 011 = (\K3) 100 = (\K4) 101 = (\K5) (Default) Bit 6,7 - MNP Block Size 00 = 64 Characters (\A0) 01 = 128 Characters (\A1) (Default) 10 = 192 Characters (\A2) 11 = 256 Characters (\A3) Value may be stored in user profiles with the &Wn command. S41 Compression Controls Default: 131, ('10000011'b) Bit 0,1 - MNP Compression Selection 00 = Disabled (%C0) 01 = MNP5 (%C1) 10 = V.42bis (%C2) 11 = MNP5 & V.42bis (%C3) (Default) Bit 2,6 - Auto Retrain - Fall back/Fall forward 00 = Retrains & Fall back/Fall forward Disabled (%E0) (Default) 10 = Retrains Enabled (%E1) 01 = Fall back/Fall forward Enabled (%E2) Bit 3 - Reserved Bit 4 - Reserved Bit 5 - Reserved Bit 6 - Reserved Bit 7 - Fall back to V.22/V.22bis 0 = Disabled (-Q0) 1 = Enabled (-Q1) (Default) Value may be stored in user profiles with the &Wn command. S42 - S45 Reserved S46 V.42bis Data Compression This register controls the selection of V.42bis data compression. Default: 138 Value 136 = Execute error correction with no data compression Value 138 = Execute error correction with data compression (default) Value may be stored in user profiles with the &Wn command. S47 Reserved S48 V.42 Negotiation This register controls the selection of V.42 error correction. Default: 7, ('00000111'b) Value 0 = Disable negotiation. Force LAPM Connection (i.e. capabilities of remote modem are known). Value 7 = Enable Negotiation Phase (default) Value 128 = Disable negotiation. Force to S36(MNP/V.42) Value may be stored in user profiles with the &Wn command. S49 - S81 Reserved S82 Break Handling Option This register is included for compatibility only. The value programmed into this register has no affect on the modem's operation. S83 - S85 Reserved S86 Connection Failure Code This register holds the connection failure cause code. When the modem issues “NO CARRIER”, this register value tells that why the modem disconnects the line. This is a read only register. Default: 0 Defined Values: 0 = Normal disconnect. 4 = Loss of carrier. 5 = V.42 failure 9 = The modems could not find a common protocol. 12 = Normal disconnect initiated by the remote modem. 13 = Remote modem does not respond after 10 retransmissions of the same messages. 14 = Protocol Failure S87 - S90 Reserved S91 Data Transmit Level Control This register controls the transmit level for the PSTN mode. In certain countries this cannot be changed and there are checks to control this. The units are 1dBm from 0dBm to -15dBm. Default: 10 (-10 dBm transmit level (USA ONLY)) Range: 0 to 15 dBm S92 FAX Transmit Level Control This register controls the transmit level for the FAX mode. The units are 1dBm from 0dBm to -15dBm. Default: 10 (-10 dBm transmit level (USA ONLY)) Range: 0 to 15 dBm S93 - S94 Reserved S95 Result Code Control Settings in this register can override the Wn command. Default: 0 Bit 0 - CONNECT Reporting 0 = CONNECT reports DTE speed (Default) 1 = CONNECT reports DCE speed Bit 1 - Append/ARQ to CONNECT XXXX result (Error Correcting Mode) 0 = Do not append ARQ to CONNECT XXXX messages (Default) 1 = Append ARQ to CONNECT XXXX messages Bit 2 - CARRIER XXXX Result Codes 0 = Disable CARRIER XXXX result codes (Default) 1 = Enable CARRIER XXXX result codes Bit 3 - PROTOCOL XXXX Result Codes 0 = Disable PROTOCOL XXXX result codes (Default) 1 = Enable PROTOCOL XXXX result codes Bit 4 - Reserved Bit 5 - COMPRESSION Result Codes 0 = Disable COMPRESSION result codes (Default) 1 = Enable COMPRESSION result codes Bit 6 - Reserved Bit 7 - Reserved Value may be stored in user profiles with the &Wn command. S96 - S97 Reserved S201 Cellular Transmit Level The bits in this register are set by the @Mn and :En commands to support cellular connections. Default: 32, ('00100000'b) Bit 0-4 Initial cellular power level setting (@Mn; default=@M0) Bit 5 Compromise Equalizer Enable Command (:En; default=E1) Bit 6 Reserved Bit 7 Reserved Value may be stored in user profiles with the &Wn command. USER NOTES The following user notes may help you if you are having problems. These were developed as a result of our testing of the product with many popular communications software packages. o If you are experiencing slow downs, select hardware flow control in the communications application you are using to conduct high speed file transfers . o Select "Hayes Compatible" type setting when installing or operating your communication software with this modem. o This modem has been extensively tested with numerous software programs, however because it uses the latest technology to achieve the 28.8Kbps speed some communication software may not have Serial port speed settings that fully utilize this speed. o When using Procomm Plus for Windows version 2.01 choose "no" when prompted to "write configuration to the modem's memory", otherwise your communication may be at 2400 baud. Common Setup Strings Example setup strings to establish commonly used configurations. Force V.42 bis data compression with LAP-M error correction (if remote modem cannot negotiate to these settings, the modem will disconnect and respond with no carrier.) AT\N4%C2-K0 Force V.42 bis data compression with MNP error correction (if remote modem cannot negotiate to these settings, the modem will disconnect and respond with no carrier.) AT\N5%C2 Force MNP 5 data compression with MNP error correction (if remote modem cannot negotiate to these settings, the modem will disconnect and respond with no carrier.) AT\N5%C1 Auto negotiate data compression and error correction. Select MNP 10 over LAP-M, LAP-M over MNP 4, and V.42 bis over MNP 5. If error correction is not negotiated, the modem will connect in normal mode. AT&F (Factory Defaults), or AT\N3%C3