V.34 Faxmodem (250-3037) Extended AT Command Set Faxback Doc. # 14542 Wn - Connect Message Control This command controls the format of CONNECT messages. The parameter value, if valid, is written to S31 bits 2 and 3. Note that the Wn command can be overridden by register S95 bits (see S95 description). W0 Upon connection, the modem reports only the PC speed (e.g., CONNECT 28800). Subsequent responses are disabled. (Default.) W1 Upon connection, the modem reports the line speed, the error correction protocol, and the PC speed, respectively. Subsequent responses are disabled. W2 Upon connection, the modem reports the modem speed (e.g., CONNECT 28800). Subsequent responses are disabled. Xn - Extended Result Codes: This command selects which subset of the result messages will be used by the modem to inform the PC of the results of commands. If the user wishes to enforce dial tone detection, a "W" can be placed in the dial string (see D command). Note that the information below is based upon the default implementation of the x results table. The Result Code Table indicates the messages which are enabled for each x value. X0 Disables monitoring of busy tones when connection is established by blind dialing; send only OK, CONNECT, RING, NO CARRIER, ERROR, and NO ANSWER result codes. X1 Disables monitoring of busy tones send only OK, CONNECT, RING, NO CARRIER, ERROR, NO ANSWER, and CONNECT XXXX (XXXX = rate). X2 Disables monitoring of busy tones unless forced otherwise by country requirements; send only OK, CONNECT, RING, NO CARRIER, ERROR, NO DIALTONE, NO ANSWER, and CONNECT XXXX. X3 Enables monitoring of busy tones; send only OK, CONNECT, RING, NO CARRIER, ERROR, NO ANSWER, and CONNECT XXXX. X4 Enables monitoring of busy tones; send all messages. Yn - Long Space Disconnect This command enables/disables the generation and response to long space disconnect. The parameter value, if valid, is written to S21 bit 7. Y0 Disables long space disconnect. (default.) Y1 Enables long space disconnect. In non-error correction mode, the modem will send a long space of four seconds prior to going on-hook. In error correction mode, the modem will respond to the receipt of a long space. Zn - Soft Reset and Restore Profile The modem performs a soft reset and restores (recalls) the configuration profile according to the parameter supplied. If no parameter is specified zero is assumed. Z0 Soft reset and restore stored profile 0. Z1 Soft reset and restore stored profile 1. &Cn - (DCD) Option Determines the way the modem controls the DCD signals to the PC. &C0 Maintains an ON condition on DCD and ignores the actual state of the data carrier defect signal from the remote modem. &C1 Tracks the state of the data carrier detect from the remote modem. &Dn - DTR Option &D0 The modem ignores DTR (default). &D1 The modem goes into command mode if an on-to-off transition is detected on DTR. &D2 When on line with a host system the modem goes on hook and assumes command mode upon detecting an on-to-off transition on DTR. Auto answer does not function when DTR is off (low). &D3 An on-to-offtransition on DTR causes the modem to go through an initialization sequence. Default values for all commands and registers are reinstated. &Fn - Restore Factory Configuration (Profile) The modem loads the factory default configuration (profile). &F0 Restore factory configuration 0. &F1 Restore factory configuration 1. &Gn - Select Guard Tone &G0 No guard tone (default). &G1 550 Hz guard tone. &G2 1800 Hz guard tone. This command controls the guard tone when your modem is in a CCITT mode. The modem never sends a tone in Bell modes. &Jn - Telephone Jack Control This command is only included for compatibility and performs no function except to load the S-Register. The parameter value if valid is written S21 bit 1. &J0 &J0 command. (Default.) &J1 &J1 command. &Kn - Flow Control This determines how the modem controls the flow of data between the local PC and the local modem. &K0 Disables flow control. &K3 Enables RTS/CTS (hardware) flow control. (Default for data modem modes.) &K4 Enables XON/XOFF (software) flow control. &K5 Enables transparent XON/XOFF (software) flow control. &K6 Enables both RTS/CTS (hardware) and XON/XOFF (software) flow control. (Default for fax modem modes.) &Ln - Leased Line Operation This command controls the selection of leased line or dial-up line. This modem supports only a single line. However if &L1 is selected the modem will respond with OK. &L0 Dial-up line (default) &L1 Leased line (not supported) &Mn - Asynchronous/Synchronous Mode Selection This command determines the DTR (asynchronous/synchronous) operating mode. The modem treats the &M command as a subset of the &Q command. &M0 Selects direct asynchronous operation. &M1 Selects synchronous connect mode with async off-line command mode. &M2 Selects synchronous connect mode with async off-line command mode. &M3 Selects synchronous connect mode. &Pn - Select Pulse Dial Make/Break Ratio This command determines the make/break ratio used during pulse dialing. The parameter value if valid is written to S28 bits 3 and 4. &P0 Selects 39%-61% make/break ratio at 10 pulses per second. (Default.) &P1 Selects 33%-67% make/break ratio at 10 pulses per second. &P2 Selects 39%-61% make/break ratio at 20 pulses per second. &P3 Selects 33%-67% make/break ratio at 20 pulses per second. Result Codes: OK n=0 to 3 ERROR Otherwise. &Qn - Sync/Async Mode This command is an extension of the &M command and is used to control the connection modes permitted. It is used in conjunction with S36 and S48 (Also see \N ) NOTE: When the &Q0 to &Q4 command is issued to select the mode the subsequent connect message will report the modem speed regardless of the W command and S95 settings. &Q0 Selects direct asynchronous operation The value 000b is written to S27 bits 3,1, and 0 respectively See &M0. &Q1 Selects synchronous connect mode with async off-line command mode. The value 001b is written to S27 bits 3, 1, and 0 respectively See &M 1 (for external modem only). &Q2 Selects synchronous connect mode with async off-line command mode and enables DTR dialing of directory 0 The value 010b is written to S27 bits 3,1, and 0 respectively See &M2 (for external modem only) &Q3 Selects synchronous connect mode with async off-line command mode and enables DTR lo act as Talk/Data switch. The value 011b is written to S27 bits 3, 1 and 0 respectively See &M3 (for external modem only). &Q4 Selects AutoSync operation The value 100b is written to S27 bits 3, 1 and 0, respectively. AutoSync operation when used in conjunction with the Hayes Synchronous Interface (HSI) capability in the PC provides synchronous communication capability from an asynchronous terminal Starting AutoSync. Set registers Sl9 S20 and S25 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 S25 before examining DTR If DTR is on the modem enters the synchronous operating state; if DTR is off the modem terminates the line connection and returns to the asynchronous command 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 the 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 The modem will try to negotiate an error-corrected link. The modem can be configured using S36 to determine whether a failure will result in the modem returning on-hook or will result in fallback to an asynchronous connection. The value 101b is written to S27 bits 3,1, and 0 respectively (Default.) &Q6 Selects asynchronous operation in normal mode (speed buffering). The value 110b is written to S27 bits 3 1 and 0 respectively. &Rn - RTS/CTS Option This selects how the modem controls the flow of data between the PC and the modem. CTS operation is modified if hardware flow control is selected (see &K command). The parameter value if valid is written to S21 bit 2. &R0 Sets the CTS in response to RTS Modem responds with OK. &R1 Allows the modem to ignore RTS The modem turns on RTS when it is on-line and ready to receive synchronous data CTS remains on until the modem hangs up. This mode would not be used if half- duplex operation is intended CTS is always on in the asynchronous command state (default). &Sn - DSR Override This command selects how the modem will control DSR. The parameter value if valid is written to S21 bit 6. &S0 DSR will remain ON at all times (Default ) &S1 DSR will become active after answer tone has been detected and inactive after the carrier has been lost. &Tn - Test and Diagnostics See Faxback Doc. # QQQQQ. &V - Display Current Configuration and Stored Profiles Reports the current (active) configuration the stored (user) profiles and the first four stored telephone numbers. The stored profiles and telephone numbers are not displayed if the NVRAM is not installed or is not operational as detected by the NVRAM test during reset processing Example: AT&V ACTIVE PROFILE: B0 E1 L1 Ml N1 Q0 T V1 W0 X4 Y0 &C0 &D0 &G2 &J0 &K3 &Q5 &RI &S0 &T4 &X0 &Y0 S00:002 S01:000 S02:043 S03:013 S04:010 S05:008 S06:002 S07:030 S08:002 S09:006 S10:014 S11:255 S12:050 S18:000 S25:005 S26:001 S36:007 S37:000 S38:020 S44:020 S46:138 S48:007 S95:000 STORED PROFILE 0: B0 El L1 Ml N1 Q0 T V1 W0 X4 Y0 &C0 &D0 &G2 &10 &K3 &Q5 &RI &S0 &T4 &X0 S00:002 S01:000 S02:043 S03:013 S04:010 S05:008 S06:002 S07:030 S08:002 S09:006 S10:014 S11:255 S12:050 S18:000 S25:005 S26:001 S36:007 S37:000 S38:020 S44:020 S46:138 S48:007 S95:000 STORED PROFILE 1: B0 El L1 Ml N1 Q0 T V1 W0 X4 Y0 &C0 &D0 &G2 &10 &K3 &Q5 &R1 &S0 &T4 &X0 S00:002 S01:000 S02:043 S03:013 S04:010 S05:008 S06:002 S07:030 S08:002 S09:006 S10:014 S11:255 S12:050 S18:000 S25:005 S26:001 S36:007 S37:000 S38:020 S44:020 S46:138 S48:007 S95:000 TELEPHONE NUMBERS: O = 1 = 2 = 3 = OK &Wn - Store Current Configuration Saves the current (active) configuration (profile), including S-Registers, in one of the two user profiles in NVRAM as denoted by the parameter value. The current configuration is comprised of a list of storable parameters illustrated in the &V command. These settings are restored to the active configuration upon receiving an Zn command or at power up (see &Yn command). &W0 Store the current configuration as profile 0. &W1 Store the current configuration as profile 1. &Xn - Select Synchronous Clock Source Selects the source of the transmit clock for the synchronous mode of operation. In asynchronous mode, the transmit and receive clocks are turned OFF. In synchronous mode, the clocks are turned ON with the frequency of 1200 Hz or faster corresponding to the speed that is selected for modem operation. &X0 Selects internal timing. &X1 Selects external timing. &X2 Selects the remote modem clock signal. &Yn - Designate a Default Reset Profile Selects which user profile will be used after the modem is switched ON or after a restart. &Y0 The modem will use profile 0. &Y1 The modem will use profile 1. &Zn=x - Store Telephone Number It is use to storing up to four telephone numbers into the NVRAM. Each telephone number dial string can contain up to 45 digits. &Zn=x n = 0 to 3 and x = dial string. (Requires 256-byte NVRAM.) %En - Enable/Disable Line Quality Monitor and Auto-Retrain or Fallback/ Fall Forward Controls whether or not the modem will automatically monitor the line quality and request a retrain (%E1) or fall back when line quality is insufficient or fall forward when line quality is sufficient (%E2). The parameter value, if valid, is written to S41 bits 2 and 6. If enabled, the modem attempts to retrain for a maximum of 30 seconds. %E0 Disable line quality monitor and auto-retrain. (Default.) %E1 Enable line quality monitor and auto-retrain. %E2 Enable line quality monitor and fallback/fall forward. %L - Line Signal Level Returns a value which indicates the received signal level. The value returned is a direct indication of the receive level at the modem, not at the telephone line connector. For example, 009 = -9 dBm, 043 = -43 dBm, and so on. %Q - Line Signal Quality Reports the line signal quality. Returns the higher 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. \Gn - Modem-to-Modem Flow Control (XON/XOFF) Enables or disables modem to modem flow control during a Normal mode connection . Since the reliable link (error correction) has its own method of flow control, the AT\Gn command is ignored when error correction is selected (AT&Q5). However, the PC to modem flow control remains active during a reliable link. The Parameters are n=0, 1 (if n is greater than 1, 1 is used). Default: 0 AT\G0 = Disables flow control (XON\XOFF). AT\GI = Enables flow control (XON\XOFF). \Kn - Break Control Controls the response of the modem to a break received from the PC or the remote modem or the \B command according to the parameter supplied. The parameter value, if valid, is written to S40 bits 3, 4, and 5. The response is different in three separate states. The first case is where the modem receives a break from the PC when it is operating in data transfer mode: \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 0. \K3 Send break to remote modem immediately. \K4 Same as 0. \K5 Send break to remote modem in sequence with transmitted data. (Default.) The second case is where the modem is in the on-line command state (waiting for AT commands) during a data connection, and the \B is received in order to send a break to the remote modem: \K0 Clear data buffers and send break to remote modem. \K1 Clear data buffers and send break to remote modem. (Same as 0.) \K2 Send break to remote modem immediately. \K3 Send break to remote modem immediately. (Same as 2.) \K4 Send break to remote modem in sequence with data. \K5 Send break to remote modem in sequence with data. (Same as 4.) (Default.) The third case is where a break is received from a remote modem during a non-error corrected connection: \K0 Clears data buffers and sends break to the PC. \K1 Clears data buffers and sends break to the PC. (Same as 0.) \K2 Send a break immediately to PC. \K3 Send a break immediately to PC. (Same as 2.) \K4 Send a break in sequence with received data to PC. \K5 Send a break in sequence with received data to PC. (Same as 4.) (Default.) \Nn - Operating Mode This command controls the preferred error correcting mode to be negotiated in a subsequent data connection. \N0 Selects normal speed buffered mode (disables error-correction mode). (Forces &Q6.) \N1 Serial interface selected - Selects direct mode and is equivalent to &M0, &Q0 mode of operation. (Forces &Q0.) For internal modem - Same as \N0. \N2 Selects reliable (error-correction) mode. The modem will first attempt a LAPM (V.42) connection and then an MNP connection. Failure to make a reliable connection results in the modem hanging up. (Forces &Q5, S36=4, and S48=7.) \N3 Selects auto reliable mode. This operates the same as \N2 except failure to make a reliable connection results in the modem falling back to the speed buffered normal mode. (Forces &Q5 S36=7, and S48=7.) \N4 Selects LAPM error-correction mode. Failure to make an LAPM error-correction connection results in the modem hanging up. (Forces &Q5 and S48=0.) Note: \N5 Selects MNP error-correction mode. Failure to make an MNP error-correction connection results in the modem hanging up. (Forces &Q5, S36=4, and S48=128.) DATA COMPRESSION AND ERROR CORRECTION COMMANDS %C - Enable/Disable Data Compression Enables or disables data compression negotiation. %C0 Disables data compression. Resets S46 bit 1. %C1 Enables MNP 5 data compression negotiation. Resets S46 bit 1. %C2 Enables V.42 bis data compression. Sets S46 bit 1. %C3 Enables both V.42 bis and MNP 5 data compression. Sets S46 bit 1. (Default.) \An - Select Maximum MNP Block Size The modem will operate an MNP error corrected link using a maximum block size controlled by the parameter supplied. \A0 64 characters. \A1 128 characters. (Default.) \A2 192 characters. \A3 256 characters. \Bn - Transmit Break to Remote In non-error correction mode, the modem will transmit a break signal to the remote modem with a length in multiples of 100 ms according to parameter specified. If a number in excess of 9 is entered, 9 is used. The command works in conjunction with the \K command. In error correction mode, the modem will signal a break through the active error correction protocol, giving no indication of the length. \B1-\B9 Break length in 100 ms units. (Default = 3.) (Non-error corrected mode only.) \Ln - MNP Block/Stream Mode Select At connection time, this command controls the selection between block and stream modes of operation in MNP. \LO Use stream mode for MNP connection. (Default.) \L1 Use interactive block mode for MNP connection. This command will accept block mode but implement stream mode. (ALL-04/07/95)