V.34 Faxmodem (250-3037) AT Commands, Basic Faxback Doc. # 14485 ┌───────────┬──────────┬──────────────────────────────────────────────────┐ │ Command │ Default │ Function │ ├───────────┼──────────┼──────────────────────────────────────────────────┤ │ A/ │ │ Re-execute command │ │ A │ │ Go off-hook and attempt to answer a call. │ │ B0 │ │ Select V.22 connection at 1200 bps. │ │ B1 │ * │ Select Bell 212A connection at 1200 bps. │ │ C1 │ * │ Return OK message. │ │ Dn │ │ Dial modifier. (see Dial Modifier) │ │ E0 │ │ Turn off command echo. │ │ E1 │ * │ Turn on command echo. │ │ F0 │ │ Select auto-detect mode (equivalent to N1). │ │ F1 │ * │ Select V.21 or Bell 103. │ │ F2 │ │ Reserved. │ │ F3 │ │ Select V.23 line modulation. │ │ F4 │ │ Select V.22 or Bell 212A 1200 bps line speed. │ │ F5 │ │ Select V.22 bis line modulation. │ │ F6 │ │ Select V.32 bis or V.32 4800 line modulation. │ │ F7 │ │ Select V.32 bis 7200 line modulation. │ │ F8 │ │ Select V.32 bis or V.32 9600 line modulation. │ │ F9 │ │ Select V.32 bis 12000 line modulation. │ │ F10 │ │ Select V.32 bis 28800 line modulation. │ │ F13 │ │ Select V.FC 28800 line modulation. │ │ F14 │ │ Select V.FC 16800 line modulation. │ │ F15 │ │ Select V.FC 19200 line modulation. │ │ F16 │ │ Select V.FC 22160 line modulation. │ │ F17 │ │ Select V.FC 24400 line modulation. │ │ F18 │ │ Select V.FC 26400 line modulation. │ │ F19 │ │ Select V.FC 28800 line modulation. │ │ H0 │ │ Initiate a hang-up sequence. │ │ H1 │ │ If on-hook, go off-hook and enter command mode. │ │ I0 │ │ Report product code. │ │ I1 │ │ Report pre-computed checksum. │ │ I2 │ │ Report OK. │ │ I3 │ │ Report firmware revision, model, and interface │ │ │ │ type. │ │ I4 │ │ Report response. │ │ I5 │ │ Report the country code parameter │ │ I6 │ │ Report modem data pump model and code revision. │ │ L0 │ │ Set low speaker volume. │ │ L1 │ │ Set low speaker volume. │ │ L2 │ * │ Set medium speaker volume. │ │ L3 │ │ Set high speaker volume. │ │ M0 │ │ Turn speaker off. │ │ M1 │ * │ Turn speaker on during handshaking and turn │ │ │ │ speaker off while receiving carrier. │ │ M2 │ │ Turn speaker on during handshaking and while │ │ │ │ receiving carrier. │ │ M3 │ │ Turn speaker off during dialing and receiving │ │ │ │ carrier and turn speaker on during answering. │ │ N0 │ │ Turn off Automode detection. │ │ N1 │ * │ Turn on Automode detection. │ │ O0 │ │ Go on-line. │ │ O1 │ │ Go on-line and initiate a retrain sequence. │ │ P │ │ Force pulse dialing. │ │ Q0 │ * │ Allow result codes to PC. │ │ Q1 │ │ Inhibit result codes to PC. │ │ Sn │ │ Select S-Register as default. │ │ Sn? │ │ Return the value of S-Register n. │ │ =v │ │ Set default S-Register to value v. │ │ ? │ │ Return the value of default S-Register. │ │ T │ │ Force DTMF dialing. │ │ V0 │ │ Report short form (terse) result codes. │ │ V1 │ * │ Report long form (verbose) result codes. │ │ W0 │ * │ Report PC speed in EC mode. │ │ W1 │ │ Report tine speed, EC protocol and PC speed. │ │ W2 │ │ Report modem speed in EC mode. │ │ X0 │ │ Report basic call progress result codes, │ │ │ │ i.e., OK, CONNECT, RING, NO CARRIER (also, │ │ │ │ for busy, if enabled, and dial tone not │ │ │ │ detected), NO ANSWER and ERROR. │ │ X1 │ │ Report basic call progress result codes and │ │ │ │ connections speeds (OK, CONNECT, RING, NO │ │ │ │ CARRIER (also, for busy, if enabled, and dial │ │ │ │ tone not detected), NO ANSWER, CONNECT XXXX, │ │ │ │ and ERROR. │ │ X2 │ │ Report basic call progress result codes and │ │ │ │ connections speeds, i.e., OK, CONNECT, RING, │ │ │ │ NO CARRIER (also, for busy, if enabled, and │ │ │ │ dial tone not detected), NO ANSWER, CONNECT │ │ │ │ XXXX, and ERROR. │ │ X3 │ │ Report basic call progress result codes and │ │ │ │ connection rate, i.e., OK, CONNECT, RING, NO │ │ │ │ CARRIER, NO ANSWER, CONNECT XXXX, BUSY, and │ │ │ │ ERROR. │ │ X4 │ * │ Report all call progress result codes and │ │ │ │ connection rate i.e., OK, CONNECT, RING, NO │ │ │ │ CARRIER, NO ANSWER, CONNECT XXXX, BUSY, NO │ │ │ │ DIAL TONE and ERROR. │ │ Y0 │ * │ Disable long space disconnect before on-hook. │ │ Y1 │ │ Enable long space disconnect before on-hook. │ │ Z0 │ │ Restore stored profile 0 after warm reset. │ │ Z1 │ │ Restore stored profile I after warm reset. │ │ &CO │ * │ Force DCD active regardless of the carrier │ │ │ │ state. │ │ &C1 │ │ Allow DCD to follow the carrier state. │ │ &D0 │ * │ Interpret DTR ON-to-OFF transition per &On. │ │ &D1 │ │ Interpret DTR ON-to-OFF transition per &Qn. │ │ &D2 │ │ Interpret DTR ON-to-OFF transition per &Qn. │ │ &D3 │ │ Interpret DTR ON-to-OFF transition per &Qn. │ │ &F0 │ │ Restore factory configuration 0. │ │ &F1 │ │ Restore factory configuration 1. │ │ &G0 │ * │ Disable guard tone. │ │ &G1 │ │ Disable guard tone. │ │ &G2 │ │ Enable 1800 Hz guard tone. │ │ &J0 │ * │ Set S-Register response only for compatibility. │ │ &J1 │ │ Set S-Register response only for compatibility. │ │ &K0 │ │ Disable PC/modem flow control. │ │ &K3 │ * │ Enable RTS/CTS PC/modem flow control. │ │ &K4 │ │ Enable XON/XOFF PC/modem flow control. │ │ &K5 │ │ Enable transparent XON/XOFF flow control. │ │ &K6 │ │ Enable both RTS/CTS and XON/XOFF flow control. │ │ &L0 │ │ Select dial up line operation. │ │ &L1 │ │ Select leased line operation. │ │ &M0 │ │ Select direct asynchronous mode. │ │ &M1 │ │ Select sync connect with async off-une command │ │ │ │ mode. │ │ &M2 │ │ Select sync connect with async off-line command │ │ │ │ mode and enable DTR dialing of directory zero. │ │ &M3 │ │ Select sync connect with async off-line command │ │ │ │ mode and enable DTR to act as Talk/Data switch. │ │ &P0 │ * │ Set 10 pps pulse dial with 39%/61% make/break. │ │ &P1 │ │ Set 10 pps pulse dial with 33%/67% make/break. │ │ &P2 │ │ Set 20 pps pulse dial with 39%161% make/break. │ │ &P3 │ │ Set 20 pps pulse dial with 33%/67% make/break. │ │ &Q0 │ │ Select direct asynchronous mode. │ │ &Q1 │ │ Select sync connect with async off-line command │ │ │ │ mode. │ │ &Q2 │ │ Select sync connect with async off-line command │ │ │ │ mode and enable DTR dialing of directory zero. │ │ &Q3 │ │ Select sync connect with async off-line command │ │ │ │ mode and enable DTR lo ad as Talk/Data switch. │ │ &Q4 │ │ Select Hayes AutoSync mode. │ │ &Q5 │ * │ Modem negotiates an error corrected link. │ │ &Q6 │ │ Select asynchronous operation in normal mode. │ │ &R0 │ │ CTS tracks RTS (async) or acts per V.25 (sync). │ │ &R1 │ * │ CTS is always active. │ │ &S0 │ * │ DSR is always active. │ │ &S1 │ │ DSR acts per V.25. │ │ &T0 │ │ Terminate any test in progress. │ │ &T1 │ │ Initiate local analog loopback. │ │ &T2 │ │ Returns ERROR result code. │ │ &T3 │ │ Initiate local digital loopback. │ │ &T4 │ * │ Allow remote digital loopback. │ │ &T5 │ │ Disable remote digital loopback request. │ │ &T6 │ │ Request an RDL without self-test. │ │ &T7 │ │ Request an RDL with self-lest. │ │ &T8 │ │ Initiate local analog loop with self-test. │ │ &V │ │ Display current configurations. │ │ &W0 │ │ Store the active profile in NVRAM profile 0. │ │ &W1 │ │ Store the active profile in NVRAM profile 1. │ │ &X0 │ │ Select internal timing for the transmit clock. │ │ &X1 │ │ Select external timing for the transmit clock. │ │ &X2 │ │ Select slave receive timing for the transmit │ │ │ │ clock. │ │ &Y0 │ │ Recall stored profile 0 upon power up. │ │ &Y1 │ │ Recall stored profile 1 upon power up. │ │ &Zn=x │ │ Store dial string x (to 45) to location n (0 │ │ │ │ to 3). │ │ %E0 │ * │ Disable line quality monitor and auto retrain. │ │ %E1 │ │ Enable line quality monitor and auto retrain. │ │ %E2 │ │ Enable line quality monitor and fallback/fall │ │ │ │ forward. │ │ %E3 │ │ Enable line quality monitor and auto-retrain │ │ │ │ with fast hang-up. │ │ %L │ │ Return received line signal level. │ │ %Q │ │ Report the line signal quality. │ │ \GO │ * │ Disable modem lo modem flow control. │ │ \G1 │ │ Enable modem to modem flow control. │ │ \Kn │ │ Controls break handling during three stales. │ │ \N0 │ │ Select normal speed buffered mode. │ │ \N1 │ │ Select direct mode. │ │ \N2 │ │ Select reliable link mode. │ │ \N3 │ │ Select auto reliable mode. │ │ \N4 │ │ Force LAPM mode. │ │ \N5 │ │ Force MNP mode. │ └───────────┴──────────┴──────────────────────────────────────────────────┘ Error Correction & Compression ┌───────────┬──────────┬──────────────────────────────────────────────────┐ │ Command │ Default │ Function │ ├───────────┼──────────┼──────────────────────────────────────────────────┤ │ %C0 │ │ Disable data compression. │ │ %C1 │ │ Enable MNP 5 data compression. │ │ %C2 │ │ Enable V.42 bis data compression. │ │ %C3 │ * │ Enable both V.42 bis and MNP 5 compression. │ │ \A0 │ │ Set maximum block size in MNP to 64. │ │ \A1 │ * │ Set maximum block size in MNP lo 128. │ │ \A2 │ │ Set maximum block size in MNP to 192. │ │ \A3 │ │ Set maximum block size in MNP to 256. │ │ \Bn │ │ Send break of n x 100 ms. │ │ \LO │ * │ Use stream mode for MNP. │ │ \L1 │ │ Use block mode for MNP. │ └───────────┴──────────┴──────────────────────────────────────────────────┘ The modem will respond to the commands detailed below. Parameters applicable to each command are listed with the command description. The defaults shown for each configuration command are those used in the factory profile 0. A/- Re-execute Command The modem behaves as though the last command line had been re-sent by the PC. "A/" will repeat all the commands in the command buffer. The principal application of this command is lo place another call (using the Dial command) that failed to connect due to a busy line, no answer, or a wrong number. This command must appear alone on a command line. This command should not be terminated by a carriage return. AT=x - Write to Selected S-Register This command writes the value x to the currently selected S-Register. An S-Register can be selected by using the ATSn command. All of the S-Registers will return the OK response if x is a number. AT? - Read Selected S-Register This command reads and displays the selected S-Register. An S-Register can be selected by using the ATSn command. A - Answer The modem will go off-hook and attempt to answer an incoming call if correct conditions are met. Upon successful completion of answer handshake, the modem will go on-line in answer mode. Bn - CCITT or Bell When the modem is configured to allow either option, the modem will select Bell or CCITT modulation for a line speed connection of 300 or 1200 bps according to the parameter supplied. Any other line speed will use a CCITT modulation standard. B0 Selects CCITT operation at 300 or 1200 bps. B1 Selects BELL operation at 300 or 1200 bps. Cn - Carrier Control This command is included for compatibility only, and has no effect other than returning a result code. The only valid parameter is 1. Dn - Dial This command directs the modem lo go on-line, dial according to the string entered and attempt to establish a connection. If no dial string is supplied, the modem will go on-line and attempt the handshake in originate mode. NOTE: If the ATD command is issued before the S1 register has cleared, the modem will respond with the NO CARRIER result code. Dial Modifiers: The valid dial string parameters are described below. Punctuation characters may be used for clarity, with parentheses, hyphen, and spaces being ignored. 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, and D. Some countries may prohibit sending of these digits during dialing. L Re-dial last number: the modem will re-dial the last valid telephone number. The L must be immediately after the D with all the following characters ignored). P Select pulse dialing: pulse dial the numbers that follow until a "T" is encountered. Affects current and subsequent dialing. Some countries prevent changing dialing modes after the first digit is dialed. T Select tone dialing: tone dial the numbers that follow until a "P" is encountered. Affects current and subsequent dialing. Some countries prevent changing dialing modes after the first digit is dialed. R This command will be accepted, but not acted on. S=n Dial the number stored in the directory (n = 0 to 3). (See &Z.) ! Flash: the modem will go on-hook for a time defined by the value of S29. Country requirements may limit the time imposed. W Wait for dial tone: the modem will wait for dial tone before dialing the digits following "W". If dial tone is not detected within the time specified by S7 (US models) or S6 (Other countries than USA), the modem will abort the rest of the sequence, return on-hook, and generate an error message. @ Wait for silence: the modem will wait for at least 5 seconds of silence in the call progress frequency band before continuing with the next dial string parameter. If the modem does not - detect these 5 seconds of silence before the expiration of the call abort timer (S7), the modem will terminate the call attempt with a NO ANSWER message. If busy detection is enabled, the modem may terminate the call with the BUSY result code. If answer tone arrives during execution of this parameter, the modem handshakes. & Wait for AT&T "bong" tone for credit card dialing before continuing with the dial string. If bong is not detected within the time specified by S7 (US models) or S6 (Other countries than USA), the modem will abort the rest of the sequence, return on-hook, and generate an error message. , Dial pause: the modem will pause for a time specified by S8 before dialing the digits following ",". ; Return to command state. Added to the end of a dial string, this causes the modem to return to the command state after it processes the portion of the dial string preceding the ";". This allows the user to issue additional AT commands while remaining off-hook. The additional AT commands may be placed in the original command line following the ";" and/or may be entered on subsequent command lines. The modem will enter call progress only after an additional dial command is issued without the ";" terminator. Use "H" to abort the dial in progress, and go back on-hook. ^ Toggles calling lone 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. Invalid character: will be ignored. En - Command Echo The modem enables or disables the echo of characters to the PC' according to the parameter supplied. E0 Disables command echo. E1 Enables command echo. (Default.) Fn - Select Line Modulation This command selects the. line modulation according to the parameter supplied. The line modulation is fixed unless Automode is selected. This command interacts with the S37 and the N command. The parameter value, if valid, is written to S37 bits 0-4. To select line modulation, it is recommended that either the F command, or a combination of the S37 and the N command, be used, but not both. F0 Selects auto-detect mode. F1 Selects V.21 or Bell 103. F2 Not supported. F3 Selects V.23. F4 Selects V.22 1200 or Bell 212A. F5 Selects V.22 bis. F6 Select V.32 bis 4800 or V.32 4800. F7 Selects V.32 bis 7200. F8 Selects V.32 bis 9600 or V.32 9600 F9 Selects V.32 bis 12000. F10 Selects V.32 bis 28800. F13 Selects V.FC 28800. F14 Selects V.FC 16800. F15 Selects V.FC 19200. F16 Selects V.FC 21600. F17 Selects V.FC 24000. F18 Selects V.FC 26400. Fl9 Selects V.FC 28800. Hn - Disconnect (Hang-Up) This command initiates a hang up sequence. H0 Go on hook (hang up). H1 Go off hook (pick up the line). In - Request product code and ROM checksum 10 display product code 11 display ROM checksum 12 display ROM checksum as OK or ERROR 13 Reports firmware revision 14 Reports product capabilities. 15 Reports Country Code parameter 16 Reports modem data pump model You use this command as a diagnostic tool when troubleshooting. Ln - Speaker Volume The modem sets the speaker volume control according to the parameter supplied. The parameter value, if valid, is written lo S22 bits 0 and 1. L0 Low volume. L1 Low volume. (Default.) L2 Medium volume. L3 High volume. Mn - Speaker Control This command selects when the speaker will be on or off. The parameter value, if valid, is written to S22 bits 2 and 3. M0 Speaker is always off. M1 Speaker is on during call establishment, but off when receiving carrier. (Default.) M2 Speaker is always on. M3 Speaker is off when receiving carrier and during dialing, but on during answering. Nn - Automode Enable This command enables or disables Automode detection. The parameter value, if valid, is written to S31 bit 1. N0 Automode detection is disabled. A subsequent handshake will be conducted according to the contents of S37 or, if S37 is zero, according to the most recently sensed PC speed. N1 Automode detection is enabled. A subsequent handshake will be conducted according to the Automode algorithm supported by the modem. This command is equivalent to F0. (Default.) 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, the enters the on-line data mode with or without a retrain. If the modem is in the off-line command mode (no connection), ERROR is reported. O0 Enters on-line data mode without a retrain. Handling is determined by the Call Establishment task. Generally, if a connection exists, this command connects the PC back to the remote modem after an escape (+++). O1 Enters on-line data mode with a retrain before returning to on line data mode. Result Codes: OK n = 0 or 1 and a connection exists. ERROR Otherwise or if not connected. P - Set Pulse Dial Default This command forces pulse dialing until the next T dial modifier or T command is received. Sets S14 bit 5. As soon as a dial command is executed which explicitly specifies the dialing mode for that particular call (e.g., ATDT...), this command is overridden so that all future dialing will be tone dialed. (See T command.) Result Code: OK Qn - Quiet Results Codes Control The command enables or disables the sending of result codes to the PC according to the parameter supplied. Q0 Enables result codes to the PC. (Default) Q1 Disables result codes to the PC. Result Codes: OK n=0 or 1. ERROR Otherwise. Sn - Read/Write S-Register The modem selects an S-Register performs an S-Register read or write function, or reports the value of an S-Register. n Establishes S-Register n as the last register accessed. n=v Sets S-Register n lo the value v. n? Reports the value of S-Register n. The parameter n can be omitted, in which case the last S-Register accessed will be assumed. The S can be omitted for AT= and AT?, in which case the last S-Register accessed will be assumed. If the number "n" is beyond the range of the S-Registers available, the modem will return the ERROR message. If the result is outside the range permitted for a given S-Register the values will still be stored, but functionally the lower and higher limits will be observed. Input and output are always in decimal format. Note that some S-Registers are read-only. In some cases, writing to the S-Register will appear to be accepted but the value will not actually be written. These are: S1 S13-S15, S17, S20-S24 and S27. T - Set Tone Dial Default This command forces DTMF dialing until the next P dial modifier or P command is received. The modem will set an S-Register bit to indicate that all subsequent dialing should be conducted in tone mode. Note that the DP command will override this command. Clears S14 bit 5. This command may not be permitted in some countries. Vn - Result Code Form Sets result code format V0 selects numeric result codes V1 selects verbal result codes (default) (ALL-04/07/95)