| Modem Command Reference |
for the
ROCKWELL CHIP SET
NOTE: The modem commands in this reference do not necessarily apply to all modems using the Rockwell chip set. On the other hand, some modems may incorporate commands not found in this reference. DIRECT Commands (Commands NOT preceded by other characters):
+++ Escape Sequence The escape sequence is used to take the modem from the on-line state to the command state, without breaking the connection. This provides a means of changing a setting then going back on-line. The escape sequence tells the modem to "escape" or leave the on-line state and enter the command state. The sequence consists of a single character issued three times in succession. A one-second "guard time" interval prevents the modem from mistaking a random occurrence of the same three characters as the escape sequence. The character used in the sequence and the duration of the guard time can be changed by writing values to S2 and S12, respectively. The escape sequence is issued by typing the plus key three times (+++) in succession. A pause of at least a second should precede and follow the three characters. The modem will return the OK result code as an indication it is ready to accept commands. See the "ATOn" command for more information about returning to on-line.
(A carriage return) Terminate connection attempt in progress during the dialing or protocol negotiation process.
A/ Re-execute Last Command Re-executes the most recent AT command string. The principle application is to place another call (e.g., Dial command) that failed to connect due to busy line, no answer, or a wrong number. This command must appear alone on a command line and be terminated by the "/" character. Ashould not be entered to terminate the command, that is, don't press "Enter". Just type "A/". Parameters : None Default : None
AT COMMANDS: AT ATtention Command defines baud rate and precedes commands. Modem commands begin with an AT prefix that gets the modem's attention. Most subsequent commands can then be concatenated into a string, terminated by a carriage return (^M or Decimal 013). The speed and character format at which the DTE ("data terminal equipment", also known as computer) sends this prefix tells the modem the speed and format for responding to commands, and at which speed to attempt the connection.
ATA Answer Modem answers the phone. This must be the last command entered in the command line. The modem proceeds with the connect sequence in answer mode. The modem will send an answer carrier signal to the originating modem and wait for an originate carrier signal. When the modem receives the carrier from the originating modem, the modems go through a handshaking process then go on-line. The modem returns the CONNECT XXXX result code. If no carrier signal is received within the time specified in register S7, the modem hangs up, returns the NO CARRIER result code, and enters command state. If no carrier is detected within the wait period in register S7 (default=50 seconds), the modem will disconnect. Any character may be entered via the DTE during the connect sequence to abort the command. Parameters : None Default : None Result codes: OK Command executed CONNECT XXXX Connection at 0 to 300 bps NO CARRIER If a connection cannot be established, the abort timer (register S7) expires, or if the command is aborted. ERROR If in data mode.
ATBn Select Communication Standard Set CCITT or BELL Mode. This command is not valid when the ATN1 command (automode detection enabled) is in effect. Parameters : 0, 1 Default : 1 for North America, 0 for Japan Result codes : OK for all valid parameters ERROR otherwise Options: ATB0 CCITT V.22 and V.21 standards for communication at 1200/300 bps. ATB1 Bell 212A and 103 standards for communication at 1200/300 bps.
ATCn Carrier Control Selection Controls the transmit carrier. The modem is preset to turn carrier on and off as necessary (ATC1). The signal is on when the modem is calling, answering, or connected to the remote modem, and is off when it is not. Parameters : 0, 1 Default : 1 Result codes: OK for 1 ERROR otherwise Options: ATC0 Transmit carrier always off. (Not supported.) ATC1 Normal transmit carrier switching (preset). Provided for backward compatibility only. Does nothing but return "OK".
ATDn Dial Command This must be the last command on the command line. ATD causes the modem to go off-hook, dial according to the parameters entered, and attempt to make a connection. The modem truncates dial strings to 40 chars. "D" places the modem in originate mode; it then functions as an auto- dialer. Whether the command is issued on a line by itself, or followed immediately by the telephone number, it must be preceded by the AT prefix and terminated with a. The dial string is a combination of dial digits and dial modifiers. The D command is not valid when the modem is on-line, or if either &Q2 or &Q3 is in effect (synchronous mode). Parentheses and hyphens in a dial string are ignored by the auto-dialer, but counted as characters in the 40-character command buffer. Parameters : 0-9 A B C D * - J K L P T R ! @ W , ; ^ S=n Default : P Result codes: OK If ";" dial modifier is used. OK If key press abort during dialing process. NO DIALTONE If ATX2 or ATX4 is selected and 1 second of dial tone is not detected within 5 seconds; or if W dial modifier is used and 3 seconds of dial tone is not detected within the time specified by register S7. BUSY If busy is detected, and ATX3 or ATX4 is selected or if W dial modifier is used. CONNECT XXXX If a connection is established. NO ANSWER If "@" dial modifier is used and 5 seconds of silence is not detected within the time specified by register S7. NO CARRIER If a connection cannot be established, the time specified in register S7 expires, or if a character is entered while dialing. ERROR If in data mode. Options: 0-9 A B C D * # These DTMF (touch-tone) codes are used to specify what digits/characters the modem will dial. - ( ) i These symbols and spaces are ignored (or invalid and therefore ignored) and may be used in the dialing string. ATDn Dial Command (continued) J Do MNP 10 link negotiation at highest rate (this call only, see *H). Not available on all modems. K Enable power level adj. during MNP 10 link negotiation. (this call only, see Mn). Not available on all modems. L Dials the last dial string that was dialed. P Use Pulse Dialing. Placed at end of command string, and before the dial string (AT...P555-5555). T Tone Dialing Method. Placed at end of command string, and before the dial string. R Reverse carrier mode. (Dial with ANSWER rather than ORIGINATE carrier.) Allows the modem to call an originate-only modem, by forcing the call into "answer mode". Must be entered as the last character of the command string. The R modifier directs the modem to act as if it had been sent an "A" command in that part of the command string. Some modems accept, but do not support, this command. Normal Mode: Calling Side: ATDTn Answering Side: ATA Reverse Mode: Calling Side: ATDTnR Answering Side: ATXD ! Hookflash. Causes the modem to go on-hook for 700 milliseconds and then off-hook. "!" issues a timed break recall signal, which causes the modem to hang up, then reconnect. (This feature can be used to access such PBX features as call transfer.) @ Wait for "quiet answer". Causes the modem to listen for 5 seconds of silence. If a 5-second silence has not been detected within the period specified in register S7, the modem disconnects and returns the NO ANSWER result code. If it detects a busy signal, it returns a BUSY result code. If the 5 seconds of silence is detected, then the modem continues dialing the dial string. This modifier is useful when dialing phone systems that produce no dial tone. ATDn Dial Command (continued) W Wait for Dial Tone Before Dialing. Causes the modem to wait for a dial tone up to the period of time specified in register S7 before dialing the number that follows. If the modem detects a dial tone before the given time delay, it continues to dial. Otherwise, it goes on-hook. , Pause During Dial is inserted between digits in a dial string. Causes the modem to pause for the value given by register S8 before dialing the next digit. This delay can be used in place of the "Wait For Dial Tone Before Dialing". A comma is frequently inserted after the "9" digit used to gain outside access from a PBX, to allow sufficient time for the dial tone to occur before the modem dials the phone number. ; Return To Command Mode After Dialing. Added to the end of the dial string. Causes the modem to remain in the command mode after it dials the digits preceding the command. This allows the user to issue additional dial commands or dial strings without overflowing the command buffer. The modem looks for the carrier after the final dial command is issued. "ATHn" aborts this command. ";" is useful calling an electronic service, such as that offered by a bank, that permits use of tones to transmit numbers once a connection has been established. ";" differs from "+++" in that the escape sequence places the modem in command state only when two modems have completed a handshake. ^ Turn On Calling Tone. Turns on the periodic 1300 Hz calling tone if originating the call. Calling tone enabled only on call-by-call basis. S=n Dial Stored Number. Follows the dial command string. Causes the modem to dial a telephone number previously stored in directory location "n" using the AT&Zn command. The "n" parameter for most modems is 0 to 3. > Generate a grounding pulse on the EARTH relay output (if the country code setting supports it). If "ATD" is entered without parameters, the modem goes off-hook and waits for a carrier; if the handshake is not completed within the time specified in register S7, the modem goes on-hook.
ATE Command Echo Controls the echo of characters received by the modem from the local DTE while the modem is in command mode. If the DTE does echo the characters you type in command state, and this function is enabled in the modem, each character typed wwiillll aappppeeaarr ttwwiiccee. Parameters : 0, 1 Default : 1 Result codes: OK for 0 and 1 ERROR otherwise Options: ATE0 Disable character echo in command state ATE1 Enable character echo in command state (usual default)
ATFn On-Line Character Echo (older modems) Determines if the modem will echo data from the DTE. The modem does not support "F0", but the modem will accept "ATF1" which might be issued by older software, so it is provided for backward compatibility. Parameters : n = 0, 1 Default : 1 Result codes: OK for 1 ERROR otherwise Options: ATF0 On-line echo enabled. Not supported. ATF1 Disables on-line echo
ATFn Line Select Modulation (used by the newer High-Speed modems) Selects specific speeds and protocols at which to connect with the remote modem. Except for F0, effectively precludes using v.42/v.42bis. Use either ATFn or a combination of ATS37=n and ATN0, but do NOT try to use both at the same time. Parameters : n = 0 thru 10 Default : 0 Result codes: OK for 0 through 10 on modems which support the speed and v.xx ERROR otherwise Options: ATF0 Auto-detect Mode Selection. Try rates in order from fast to slow. (Same as ATN1.) ATF1 300 bps only (protocol per the ATBn setting, v.21 or Bell 103) ATF2 Not Used (returns "OK") ATF3 v.23 only 75 send/1200 receive (originate) or 1200 send/75 receive (answer). ATF4 1200 bps only (protocol per the ATBn setting, v.22 or Bell 212A) ATF5 2400 bps only (v.22bis) ATF6 4800 bps only (v.32/v.32bis) ATF7 7200 bps only (v.32bis) ATF8 9600 bps only (v.32/v.32bis) ATF9 12000 bps only (v.32bis) ATF10 14400 bps only (v.32bis) See also: "S37" "ATNn" "ATBn"
ATHn Switch-Hook Control Applies to asynchronous operation only. If the user enters the command mode from the data mode by issuing the escape sequence (+++), or as a result of an ON-to-OFF transition of DTR of the AT&D1 option in effect, the user may cause the modem to go on-hook (disconnect) by issuing the ATH command. "H" provides control over the line relay. Its most common use is with "H0" to initiate a Hangup and place the modem on hook. "H1" takes the modem off hook. Parameters : n=0, 1 Default : none Result codes: OK for 0 and 1 ERROR otherwise Options: H0 Modem goes on-hook (hangs up). H1 Enables switchhook and auxiliary relay. Modem goes off hook, returns an OK response, and awaits further commands.
ATIn Identification Codes Returns the product code, the checksum of firmware ROM, or computes checksum of the firmware ROM and reports its error status. The product code contain 3 digits. The checksum result consists of three numeric chars followed by a. Error status is either OK or ERROR. Parameters : n = 0-3 Default : none Result codes: OK Options: I0 Displays the product ID code I1 Performs checksum on firmware ROM and displays the value. I2 Performs checksum on firmware ROM and returns ERROR or OK. I3 Reports firmware revision level. Some manufacturers include additional ATIn options, such as a modem ID string (ATI4), country code (ATI5), data pump model and revision code (ATI6), etc.
ATLn Speaker Volume Controls the internal speaker volume. Parameters : 0-3 Default : 2 Result codes: OK for 0 to 3 ERROR otherwise Options: L0 low speaker volume L1 low speaker volume L2 medium speaker volume L3 high speaker volume
ATMn Speaker Control Controls the internal speaker while the modem is receiving a carrier signal or dialing. This command also enables or disables the speaker. Parameters : n = 0-3 Default : 1 Result codes: OK for 0 to 3 ERROR otherwise Options: M0 Speaker always off. M1 Speaker on until carrier signal from remote modem is detected. M2 Speaker always on. M3 Speaker off as digits are dialed, but on during answer and on until carrier signal is detected. See also: "ATLn"
ATNn Modulation Handshake Negotiation Negotiation of Handshake Options. This is used to assure a connection is made only at the specified speed. "N"selects whether or not the local modem performs a negotiated handshake with a remote modem when the communications speeds of the two modems are different. The options for this command are useful when a particular speed and communication standard are required. Both symmetrical and asymmetrical protocols can be selected. Note: the options supported for this command vary between country-specific implementations. If a leased line is selected, this command is ignored and the modem operates as if "N0" were selected. Parameters : 0, 1 Default : 1 Result codes: OK for 0 and 1 ERROR otherwise Options: ATN0 Requires the speed of the connection be that specified by value in register S37; if S37=0, the speed of the connection must match that at which the last AT command was issued (i.e., the current serial port rate). If the selected speed can be achieved using more than one communication standard (e.g., Bell 212A or V.22 at 1200 bps), the modem also references the selection made with the ATB command. ATN1 Enables automode detection. Permits handshaking to occur at any speed supported by both modems. "ATB" is ignored in this mode and the modem attempts only CCITT-mode connections. See also: "ATBn" "S37" "ATFn"
ATOn Return To On-line Status Note: Asynchronous operation only. If the user enters command mode from data mode by issuing the an escape sequence (or as a result of an ON-to-OFF transition of DTR with the AT&D1 option in effect), the user may return to data mode without terminating a call by issuing "ATOn". This may also be used to force a retrain -- if "O1" is issued, the modem goes back on-line and retrains its adaptive equalizer. Parameters : 0, 1 Default : none Result codes: ERROR If &T1, &T3, or &T6-&T8 is active CONNECT XXX If a connection is established NO CARRIER If retrain not successful in time specified by register S7 Options: ATO0 Returns to on-line; causes modem to return to data mode. ATO1 Returns to on-line with retrain. Causes modem to return to data mode and initiate a retrain when operating at 2400, 4800, 9600, 12000, or 14400 bps. See also: "+++" "AT&Dn" "AT&Tn" "S7"
ATP Set Pulse Dial as Default Causes modem to assume all subsequent dial commands are pulse-dialed. The user may omit the "P" from the dial string. Dialed digits will be pulse dialed until a "T" or dial modifier is received. Parameters : none Default : none Result codes: OK (If issued outside dial string) See also: "ATDn" "ATP"
ATQn Result Code Display Determines whether or not the modem sends the result codes to DTE. (See ATXn command.) "Qn" controls whether result codes generated by the modem are displayed to the attached computer/DTE. Some software does not function properly when modem responses are returned. Parameters : n = 0, 1, 2 Default : 0 Result codes : OK for 0 and 2 NONE for 1 ERROR otherwise Options: Q0 Allows modem to send the result codes to the DTE. Q1 Prohibits modem from sending result codes to the DTE. Q2 Modem returns result codes to DTE when originating a call; does not return result codes when answering a call with the exception of OK and ERROR. See also: "ATXn"
ATSr? Report value in S Register r and ATSr=x Write value x into S Register r Parameters : r = 0-95, x = 0-255 Default : none Result codes: OK for parameters n=0-95 OK for no argument ERROR otherwise Options: ATSr Addresses an S-register "Sr" points to a specific S-Register. Subsequent commands, such as "?" and "=", may read or write to the selected register. ATSr=n Sets S-register "r" to value "n" Writing to S registers: writes the value of "n" to the specified S register. All registers will return an OK response if "n" is a legal value, however, some registers will not actually write the value anywhere. These registers are S1, S13-S15, S17, S20 to S24, and S27. ATSr? Display contents of S register "r" The contents of S register "r" are sent to the screen as three decimal digits. This text response is formatted with(as determined by the "ATVn" command currently in effect). See also: "ATVn" "ATZn" "AT&F"
ATT Set Tone Dial as Default Causes modem to assume all subsequent dial commands are tone dialed (DTMF). The user may omit the "T" from the dial string. Dialed digits will be tone dialed until a P command or dial modifier is received. Parameters : none Default : none Result codes: OK (If issued outside dial string.) See also: "ATDn" "ATP"
ATVn Result Code Form (Message Control) Selects whether modem sends long or short form result codes to the DTE. All responses are ASCII values. Long-form (verbose) responses are preceded and terminatedcharacters. Short-form (numeric) responses are only terminated with a . (See ATXn command.) Parameters : 0, 1 Default : 1 Result codes: 0 for 0 OK for 1 ERROR otherwise Options: ATV0 Display result codes in numeric form (short) ATV1 Display result codes in verbose form (as words)
ATWn Negotiation Progress Reporting An additional set of result codes can be enabled with "W" to report progress of the negotiation phase of error-correction mode. These codes report carrier speed (300-14400 bps) and error-correction protocol. These messages can also be reported in either numeric or verbose form. For example, both 77 and PROTOCOL:LAP-M indicate the error-correction is LAP-M (See ATXn command.) "W" works in conjunction with register S95 to determine which result codes are used to describe the connection and protocol, etc., that result from handshaking and negotiation. When the modem is operated in error-control mode (&Q5 is in effect), "W" and register S95 allow the user to select these additional result codes: CARRIER, PROTOCOL, AUTOSTREAM, COMPRESSION, CONNECT If the error-correction link is negotiated and the connection is made, the appropriate CONNECT XXXX message is reported. When in error- correction mode, the CARRIER XXXX message may indicate one speed, while the CONNECT XXXX message reports another. Parameters : 0-2 Default : 0 Result codes: OK for parameters 0-2 ERROR otherwise Options: ATW0 Error-correction call progress not reported. ATW1 Error-correction call progress reported. ATW2 Error-correction call progress not reported. CONNECT XXXX message reports DCE speed. Note that selecting W0 and setting S95=12 is the same as selecting W1; and that selecting W0 and setting S95=1 is the same as selecting W2. S95 cannot be configured to force W2 to report DTE speed in the CONNECT result code; and there is no setting of S95 that will force W1 not to produce the CARRIER and PROTOCOL result codes. S95 extends the functionality of the W command. Selecting W0 and setting S95 as required allows you to tailor result codes characteristics to your own requirements. See also: "ATVn" "ATXn" "AT&Qn" "S95"
ATXn Extended Result Codes Determines whether the modem responds to dial tone and busy signals, and how it displays result codes for CONNECT messages. When the modem ignores dialtone, it waits for a time delay given by register S6 and then "blind" dials (regardless of presence or absence of dial tone). "X" enables tone detection options used in the dialing process. As these are enabled/disabled, the result code reporting is also affected. This command is frequently used to control the modem's range of responses; however, its primary function is controlling the modem's call response capabilities. Parameters : 0-4 Default : 4 Result codes: OK for parameters 0-4 ERROR otherwise Options: ATX0 CONNECT XXXX result codes enabled. Modem ignores dial tone and busy signal. Sends CONNECT message when a connection is established by blind dialing (and no indication of phoneline speed). This setting overrides any other result code selections made with "W" and register S95. ATX1 CONNECT XXXX result codes enabled; dial tone and busy signal not detected. "W" options and register S95 selections are enabled. ATX2 Modem ignores busy signal but waits for dial tone before dialing. If dial tone is not detected within 5 seconds, the NO DIAL TONE message is sent. Sends CONNECT XXXX result code reflecting linespeed when a connection is made by blind dialing. "W" and S95 are enabled. ATX3 Modem ignores dial tone. Sends CONNECT XXXX reflecting linespeed. Sends BUSY if busy signal is detected. "W" and S95 are enabled. ATX4 If dial tone is not detected within 5 seconds, sends NO DIAL TONE message. If busy signal is detected, sends BUSY message. Sends CONNECT XXXX message reflecting linespeed. "W" and S95 enabled. ATXn Extended Result Codes (continued) Result Codes - Q, V, X, W, S95 Short Long Form 0 OK X0 X1 X2 X3 X4 1 CONNECT X0 X1 X2 X3 X4 2 RING X0 X1 X2 X3 X4 3 NO CARRIER X0 X1 X2 X3 X4 4 ERROR X0 X1 X2 X3 X4 5 CONNECT 1200 X1 X2 X3 X4 6 NO DIALTONE X2 X4 7 BUSY X3 X4 8 NO ANSWER 9 CONNECT 0600 10 CONNECT 2400 11 CONNECT 4800 12 CONNECT 9600 16 CONNECT 19200 17 CONNECT 38400 18 CONNECT 57600 33 FAX 34 FCERROR 35 DATA 40 CARRIER 300 46 CARRIER 1200 47 CARRIER 2400 49 CARRIER 7200 50 CARRIER 9600 51 CARRIER 12000 52 CARRIER 14400 66 COMPRESSION CLASS 5 67 COMPRESSION V.42BIS 69 COMPRESSION NONE 70 PROTOCOL:NONE 77 PROTOCOL:LAPM 80 PROTOCOL:ALT See also: "ATQn" "ATVn" "ATWn" "S6" "S95"
ATYn Control Long Space Disconnect Determines whether modem disconnects when it receives a continuous break froma remote modem for a period >= 1.6 seconds, and sends a break for 4 seconds before disconnecting due to ON-to-OFF transition of DTR if "AT&D2" is in effect, or upon receiving an ATH command. If Y1 is selected, the modem will send a 4-second break before going on hook when "ATH0" is issued or, if &D2 is selected, when DTR goes off. Parameters : 0, 1 Default : 0 Result codes: OK for 0 and 1 ERROR otherwise Options: ATY0 Disable long space disconnect ATY1 Enable long space disconnect See also: "AT&Dn"
ATZn Soft Reset and Load Stored Profile Causes modem to disconnect and perform a warm start. Must be the last command on the command line. The reset actions are: ~ Clear serial port buffers. ~ Set baud rate and parity to match local DTE when any AT command is issued. ~ Restore active configuration with user profile denoted by the parameter. The command tells the modem to go on hook and restore the selected stored profile. Any non-storable parameters previously set by commands are returned to factory settings. Refer to "&W" command for a description of which parameters are included in a stored profile. Parameters : 0, 1 Default : 0 Result codes: OK for 0 and 1 ERROR otherwise Options: Z Load stored default profile (whichever is selected by AT&Yn) Z0 reset modem and recall user profile 0 (stored with AT&W0) Z1 reset modem and recall user profile 1 (stored with AT&W1) See also: "AT&Wn" "AT&Yn"
AT&Cn DCD (RLSD) Signal Control Controls the Received Line Signal Detected (RLSD) [Data Carrier Detect (DCD)] (pin 8) signal of the serial port. If synchronous mode is selected, this is ignored and the modem functions as if AT&C1 has been entered. "&C" determines how the state of the DCD lead relates to the carrier from the distant end. The command will take effect immediately when issued. The behavior patterns for DCD depend on the specific &C and &Q commands in effect. Also, DCD patterns depend on whether on-line operation is half or full duplex. Finally, if &Q5 is in effect, DCD behavior depends on whether S10=255 or S10<255. DCD circuit operation is according to the descriptions below. Parameters : n = 0, 1 Default : 0 Result codes: OK for 0 and 1 ERROR otherwise Options: AT&C0 RLSD is ON regardless of the state of the data carrier from the remote modem. AT&C1 RLSD follows the state of the data carrier from the remote modem. See also: "AT&Qn" "S10" "EIA 232-D Signal"
AT&Dn DTR Option Determines actions taken by the modem in relation to the Data Terminal Ready (DTR) signal (pin 20) of the serial port. The effect of DTR loss depends upon the AT&D and AT&Qn commands. "&D" affects how the modem will respond to the state of the DTR signal and changes to this circuit. Parameters : n = 0 to 3 Default : 0 Result codes: OK for 0 to 3 ERROR otherwise The action for the event that follows DTR loss is indicated below: &D0 &D1 &D2 &D3 *&Q0 N 2 3 4 &Q1 1 2 3 4 &Q2 3 3 3 3 &Q3 3 3 3 3 &Q4 1 2 3 4 *If AT&Q5, AT&Q6, AT&Q8, or AT&Q9 is in effect, the action taken is the same as AT&Q0. The DTR on-to-off transition (greater than S25 setting) corresponding to the numbers in the above table are: 1. Modem disconnects and sends OK result code. 2. Modem goes into asynchronous command mode if in data mode and sends the OK result code. 3. Modem disconnects, sends the OK result code, disables auto answer while DTR is OFF, and returns to the command state. 4. Modem performs a warm start (like as ATZ). This is the DTE/AT&D3 abort. See also: "AT&Qn" "AT&Tn" "EIA 232-D Signal" "S25"
AT&F Load Factory Default Configuration Loads the modem active area with the factory default values. &F recalls the configuration stored programmed in ROM at the factory. This operation completely replaces the command options and S-Register values in the active configuration. Parameters : none Default : none Result codes: OK
AT&Gn Guard Tone Select Normally controls the generation of guard tones. This command is not implemented, however the command structure is provided for application compatibility. In the Hayes AT command set, "&G" tells the modem which guard tone, if any, to transmit while transmitting in the high band (answer mode). The guard tone is transmitted only while the modem is transmitting in the answer mode and during the answer handshake. Parameters : n = 0-2 Default : 0 Result codes: OK for 0 to 2 ERROR otherwise Options: AT&G0 Disable guard tones (North America default) AT&G1 Enable 550Hz guard tone (not supported) AT&G2 Enable 1800Hz quard tone (other areas of the world)
AT&Kn DTE/Modem Flow Control "&Kn" is used to select the local flow control method used when the modem is operating in error-control mode. Determines how the modem controls the flow of data between the local DTE (computer) and the modem. When the modem terminal buffer is nearly full, the modem will either send an XOFF or drop CTS (pin 5) to stop the data flow. When the buffer is nearly empty, the modem will either send an XON or raise CTS to start the data flow. The modem also responds to XON/XOFF characters or RTS(pin 4) / CTS stimulus from the computer by suspending or resuming transmission. When in the Direct mode (AT&Q0), flow control is not used and the modem ignores the setting of this command. Parameters : n = 0, 3 to 6 Default : 3 Result codes: OK for 0, 3 to 6 ERROR otherwise Options: AT&K0 Disables flow control. May be selected for use during error- control mode at the risk of overflowing the buffers and losing data. AT&K3 Enables bidirectional hardware RTS/CTS flow control. (Preferred for all high speed connections.) AT&K4 Enables software XON/XOFF flow control. This method should not be used when XON/XOFF characters will be sent as user data or part of a file transfer protocol. AT&K5 Enables "transparent" software XON/XOFF flow control. The data stream is controlled by characters DC1 and DC3. The chars DLE, DC1, and DC3 are transparentized by sending DLE followed by the character XORed with 21hex. AT&K6 Enables both hardware RTS/CTS flow control and software XON/XOFF flow control (AT&K3 and AT&K4 combined). See also: "AT&Qn"
AT&Ln Line Type Select Control selection of leased line or dial-up line. Although the modem has only a single line connection, the power level is changed when setting leased line operation (see S91 register). Parameters : n = 0, 1 Default : 0 Result codes: OK for 0 and 1 ERROR otherwise Options: AT&L0 Dial-up line AT&L1 Leased line See also: "S91"
AT&Mn Communication Mode Same function as AT&Q0 thru AT&Q3. Parameters : n = 0-3 Default : &Qn Result codes: OK for 0-3 ERROR otherwise See also: "AT&Qn"
AT&Pn Pulse Dialing Ratio Make/Break Ratio Selection Selects the ratio of the off-hook to on-hook interval used when pulse dialing. Parameters : n = 0, 1, 2, or 3 Default : 0 for North America, 1 for UK & Honk Kong, 3 for Japan Result codes: OK for n = 0 to 3 in North America or for n = 1 or 3 in Japan ERROR otherwise Options: AT&P0 39%/61% make/break ratio @ 10 pps. (USA/Canada) AT&P1 33%/67% make/break ratio @ 10 pps. (UK/Hong Kong) AT&P2 39%/61% make/break ratio @ 20 pps. AT&P3 33%/67% make/break ratio @ 20 pps. (Japan)
AT&Qn Asynchronous/Synchronous Communication Mode Select The modem supports three basic communication modes: asynchronous, synchronous, and error correction. Synchronous and direct modes are not available when the parallel host interface is selected. "&Q" selects the communication mode. It determines how the modem will treat transmitted and received data while in the on-line state (i.e., asynchronous, synchronous, AutoSync, or error-control) and establishes certain call setup procedures. Refer also to the &C, &D, and &S commands in this section. AT&Q5 - Error Correction Mode: A V.42 product can negotiate any one of several connection types, depending on the capabilities and configuration of the remote modem. This is accomplished through an extension of the error-control mode -- &Q5. In this factory-default configuration, the modem automatically attempts to make a connection using the V.42 standard. When a V.42 product is configured to make an MNP connection, it attempts an MNP-4 connection. If you are primarily transferring precompressed files -- you do NOT want fall back to MNP-5. Therefore, select "AT&Q9". Parameters : n = 0-9 Default : 5 Result codes: OK for 0-9 AT&Qn Asynchronous/Synchronous Communication Mode Select (cont.) ERROR otherwise Options: AT&Q0 Selects asynchronous operation in the Direct mode. In this mode, the DTE speed must match the telco line speed. Also used for tests. ***** CAUTION ***** Be VERY careful when issuing the AT&Q1, AT&Q2 and AT&Q3 commands! Once you enter &Q(1-3) and save it to memory, there are only three known ways to return to Asynchronous Mode: 1. Issue AT&Q(0,5-9) &W from a Synchronous Terminal to restore the modem to Asynchronous Mode. 2. Connect modem to an Asynchronous Terminal with the DTR signal (line 20) disabled (a "break-out" box works very nicely for this) and issue the configuration you want or AT&Q(0,5-9) &W to return the modem to Asynchronous Mode. 3. Send the modem to the manufacturer's repair department. AT&Q1 Selects synchronous mode 1 operation. Supports terminals that are able to communicate in both asynchronous and synchronous protocols. Uses the dial command to place a call in asynchronous mode then switches to synchronous mode once the connection is made. The modem goes on-hook and switches back to the asynchronous mode when it detects an ON-to-OFF transition on DTR or a loss of carrier from the remote modem exceeding the time interval given by register S10. AT&Q2 Selects synchronous mode 2 operation. Supports synchronous terminals with stored number dialing. The modem automatically dials a stored number when it detects a LOW-to-HIGH (ON-to- OFF) transition on the DTR line. An asynchronous terminal is still needed to save and change the phone numbers stored in the NVRAM; the number is saved using the "AT&Z0=x" command. The modem dials the number stored in the first entry. AT&Q3 Selects synchronous mode 3 operation. This mode allows DTR to act as a Talk/Data switch. The operator manually initiates a call with DTR OFF, implying the modem is in Talk mode. To complete the call, the operator switches the modem to Data mode by turning DTR ON after the last number is dialed. The modem goes on-hook and switches to the asynchronous mode when an OFF-to-ON transition on DTR is detected or a loss of carrier occurs from the remote modem exceeding the time interval given by register S10. AT&Qn Asynchronous/Synchronous Communication Mode Select (cont.) AT&Q4 This causes the modem to issue OK result code but has no effect on operation. AT&Q5 Selects error correction mode. Modem negotiates an error- correction link in accordance with the S48 and S36 settings. The modem can be configured to either disconnect or fall back to a normal asynchronous connection if the link cannot be negotiated (refer to register S36). For example, if AT&Q5, S48=7, and S36=7 (default settings), the modem will attempt to connect in V.42, then MNP-4, then fall back to normal mode. This mode is commonly referred to as the "auto-reliable" or "asynchronous-reliable" mode. AT&Q6 Selects asynchronous operation in normal mode (Speed Buffering). In this mode, the DTE speed can differ from the telco line speed. AT&Q7 This command causes the modem to issue OK result code but has no effect on operation. AT&Q8 This command forces the modem to behave as if S48=128, that is, attempt an MNP-4 connection, then attempt normal mode if bit 1 of S36=1 or direct mode if bit 1 of S36=0. Same as AT&Q5 but without v.42/v.42bis. AT&Q9 This command behaves like AT&Q5 with S48=7 and S46=138. The modem will attempt V.42bis, fallback to V.42 (LAP-M), then fallback to normal mode. No MNP 2 thru 5 connections are attempted. See also: "AT&Cn" "AT&Dn" "AT&Sn" "S36" "S46" "S48"
AT&Rn RTS/CTS Options when in Synchronous (AT&Q1 thru AT&Q3) mode Controls the state of the CTS signal (pin 8) in synchronous modes (&Q1, &Q2, and &Q3). CTS is always on in asynchronous mode unless AT&K3 is selected. Parameters : n = 0, 1 Default : usually 0 Result codes: OK for 0 and 1 ERROR otherwise Options: AT&R0 CTS tracks RTS. CTS is turned ON in response to an OFF-to-ON transition of RTS from the local DTE (computer) after a delay period specified by register S26. AT&R1 The modem ignores RTS. CTS is held ON unless AT&K3 is selected. See also: "AT&Kn" "AT&Qn" "S26" "EIA 232-D Signal"
AT&Sn Data Set Ready (DSR) Options Determines whether DSR (pin 6) operates in accordance with EIA-232-D or remains ON. The DSR circuit indicates when the modem is connected to a communication channel and is ready. In synchronous mode, when originating a call, DSR goes high when dialing is completed and an answer tone is detected from the remote modem. When answering a synchronous call, DSR goes high when the modem begins transmitting the answer tone. In asynchronous or error-correction mode, "&S" can be used to configure the modem to keep the DSR signal high at all times, or have it operate according to the EIA 232-D specification. Parameters : n = 0, 1 Default : 0 Result codes: OK for 0 and 1 ERROR otherwise Options: AT&S0 DSR is always ON. AT&S1 DSR operates in accordance with the EIA-232-D specification. (Active following carrier tone, and until carrier is lost.) See also: "AT&Qn" "EIA 232-D Signal"
AT&Tn Test and Diagnostic Mode Selection Selects the test command. Test commands must be initiated in command mode with asynchronous operation in Direct mode selected (AT&Q0) at a speed of 1200 bps* or faster. A telco line connection must be established prior to initiating digital loopback tests. If test conditions are not met, the modem issues an ERROR result code. If local analog loopback is initiated while the modem is connected, the modem disconnects before performing the test. * Note: Supra recommends you run the tests at 2400 or 9600 bps with error correction and data compression disabled. This corresponds with issuing the command AT\N1 &K0 &Q0 &D2 N0 S37=6 for 2400 bps (S37=9 for 9600 bps). An initiated test is active for the period of time specified by register S18 before returning to command mode. If S18 is zero, the test aborts when the user issues the AT&T0 command. The following &T command options are used to configure and place the modem in various test modes as defined by CCITT V.54. These tests can be used to verify the analog and digital portions of the modem's operation, as well as those of the remote modem. Some of these tests require a connection be established before running the procedure. Parameters : 0, 1, or 3-8 Default : 4 Options: AT&T0 End test in progress. The escape sequence must be issued to return the modem to the command mode prior to sending this command. Subsequent issuing of the ATOn command while in the command mode will cause the local and remote modems to return to normal data mode operation if the interrupted test was digital loopback. AT&T1 Initiates local analog loopback. This test verifies the working condition of the path between the computer and the local modem. Characters received from DTE are looped back to the DTE by modem. ( +++ , then AT&T0 to terminate test.) AT&T2 Not implemented. Returns ERROR. AT&T3 Initiates remote digital loopback locally. The characters received from the remote modem are looped back to the remote modem by the local modem. This verifies working condition of the path from a remote modem, through a local modem, and back to the remote modem. AT&T4 Allow the modem to respond to a request from a remote modem for a remote digital loopback test. AT&T5 Prohibits the modem from granting a request from a remote modem for a remote digital loopback test. AT&Tn Test and Diagnostic Mode Selection (continued) AT&T6 Initiates remote digital loopback. The characters received from the local DTE are transmitted to the remote modem and looped back to the remote modem and looped back from the remote modem to the local modem and DTE. This test verifies the working condition of the path between the local DTE and the remote modem. AT&T7 Initiates remote digital loopback with self test. This test works similarly to AT&T6 except that the modem sends an alternating zeros and ones (0101) test pattern to the remote modem and continuously examines the validity of the returned data. The modem increments an internal error counter each time an error is detected. At the end of the test, the modem return a 3-digit error count to the DTE. AT&T8 Initiates local analog loopback with self test. This test works similarly to AT&T7 except that the test pattern is checked in the local analog loopback mode (as in AT&T1). This allows a thorough testing of the local modem transmit and receive functions without an actual telco line connection. ( +++ , then AT&T0 to stop.) See also: "ATOn" "AT&Qn" "AT&Sn" "S18"
AT&V View Current Configuration and User Profiles The &V command is used to display the active and stored profiles (commands and S-Register settings) along with any stored telephone numbers. Note: not all S registers appear without direct query (S95=?). Parameters : none Default : none
AT&Wn Store User profile Saves the current configuration into NVRAM as one of two user profiles. The current configuration is comprised of a list of storable parameters. These settings are restored to the active configuration upon receiving the ATZn command or at power up (see AT&Y). The user profile saved is denoted by the parameter value. In addition, the AT speed and parity are stored, according to the values used at the time the command is issued. Parameters : n = 0, 1 Default : none Result codes: OK for 0 and 1 ERROR otherwise Options: AT&W0 Write active profile into user profile 0 AT&W1 Write active profile into user profile 1 See also: "ATZn" "AT&Yn"
AT&Xn Synchronous Transmit Clock Source Selection Selects the source of the synchronous transmit clock for the modem during synchronous operation. In asynchronous mode, the transmit and receive clocks are turned OFF. In synchronous mode, the clocks are turned ON with the frequency of 1200Hz or faster corresponding to the speed selected for modem operation. Parameters : n = 0-2 Default : 0 Result codes: OK for 0 to 2 ERROR otherwise Options: AT&X0 Internal timing. The modem generates the transmit clock signal and applies it to the TXCLK output at the serial interface. Modem generates the transmit clock and applies it to pin 15 (EIA 232-D). AT&X1 External timing. The local DTE sources the transmit clock signal to the XTCLK input of the serial interface (pin24). The modem applies this clock to the TXCLK output (pin 15) at the serial interface. This setting is available for external modems only. AT&X2 Slave receive timing. The modem derives the transmit clock signal from the incoming carrier and applies it to the TXCLK output at the serial interface (pin 15).
AT&Yn Designate Default User Profile Designate which of two user profiles will be loaded into the active configuration at power up. The user profile is denoted by the parameter value. Parameters : 0, 1 Default : 0 Result codes: OK for 0 and 1 ERROR otherwise Options: AT&Y0 Selects user profile 0 (which was stored by AT&W0) AT&Y1 Selects user profile 1 (which was stored by AT&W1) See also: "ATZn" "AT&Wn"
AT&Zn=x Store Phone Number Stores a 36-digit dial string(x) in the specified entry(n) for later dialing (see ATDn command). If no dial string follows the command, the referenced stored number will be cleared. "&Zn" is used to store up to four dialing strings in the modem's NVRAM for later dialing. The format for the command is &Zn="stored number" where n is the location 0-3 to which the number should be written. Parameters : n = 0-3, x = dial string Default : none Result codes: OK for all parameters ERROR if storage number (n) is outside allowable range or the dial string (x) is longer than 36-digits, or if the total number of stored digits exceeds 114. See also: "ATDn"
AT\An Maximum MNP Block Transfer Control Sets the maximum block size for MNP stream link connection. Use this command to transmit smaller blocks of data in a reliable link connection. Parameters : n = 0-3 (if n>3, 3 is used.) Default : 2 Result codes: OK Options: AT\A0 Sets maximum block size to 64 characters AT\A1 Sets maximum block size to 128 characters AT\A2 Sets maximum block size to 192 characters AT\A3 Sets maximum block size to 256 characters
AT\Bn Transmit Break When this command is entered during a non-MNP connection, the modem sends a break signal to the remote modem. The length of the break is 100 times the n parameter value in milliseconds. If this command is entered in MNP-4 mode, the modem sends a Link Attention PDU to the remote modem. Parameters : n = 1-9 (if n=0, default 3 is used; if n>9, 9 is used.) Default : 3 (300 milliseconds) Result codes: OK if connected ERROR if not connected
AT\Gn Modem to Modem XON/XOFF Flow Control 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, "AT\Gn" is ignored when error correction is selected (AT&Q5). However, the DTE to modem flow control remains active during a reliable link. Parameters : n = 0, 1 (if n>1, 1 is used.) Default : 0 Result codes: OK Options: AT\G0 Disable flow control (XON/XOFF). AT\G1 Enable flow control (XON/XOFF). See also: "AT&Qn"
AT\Jn Enable DTE Auto Rate Adjustment Enables or disables Data Terminal Equipment (DTE) to adjust to the modem-to-modem connect rate. Parameters: 0, 1 Default : 0 Result codes: OK Options: AT\J0 DTE auto rate adjust is disabled. AT\J1 DTE rate is adjusted to match carrier rate.
AT\Kn Break Processing Control (Controls remote modem during MNP mode) Determines modem response when a BREAK is received from the DTE or the remote modem. During MNP-4 mode, the remote modem's BREAK control setting determines the local modem response the handle the BREAK. Parameters : n = 0-5 (if n>5, 5 is used.) Default : 5 Result codes: OK Options: When a BREAK is received from the DTE during Normal or MNP-4 mode, the modem takes the following action: AT\K0,2,4 Modem enters command mode (waiting for AT) without sending a BREAK to the remote modem. AT\K1 Modem clears the terminal and modem buffers and sends a BREAK to the remote modem. AT\K3 Modem does not clear buffers but sends a BREAK to remote modem. AT\K5 Modem sends a BREAK to the remote modem in sequence with any transmitted data. When a BREAK is received from a remote modem during Normal mode, the modem takes the following action: AT\K0,1 Modem clears the terminal and modem buffers and sends a BREAK to the local DTE. AT\K2,3 Modem does not clear buffers but sends a BREAK to local DTE. AT\K4,5 Modem sends a BREAK in sequence with any data being buffered. When a BREAK is received from the DTE during Direct mode, the modem takes the following action: AT\K0,2,4 Modem sends a BREAK to remote modem and enters command mode (waiting for AT.) AT\K1,3,5 Modem sends a BREAK to remote modem. Note: In LAPM, breaks are "timed", meaning the modem attempts to preserve the duration of the break when transmitting to the remote modem. In MNP-4, breaks are not "timed", as MNP-4 has no facility for maintaining the duration of the signal; a long break is the same as a short break.
AT\Ln MNP Block Transfer Control Determines whether the modem will use Block or Stream mode for MNP link. Parameters : n = 0, 1 (If n>1, 1 is used) Default : 0 Result codes: OK Options: AT\L0 Uses Stream mode for MNP-4 link connections. AT\L1 Uses Block mode for MNP-4 link connections.
AT\Nn Operation Mode Control Selects the operating mode the modem uses while connecting (see AT&Qn). Parameters : n = 0-3 (If n > 3, 3 is used) Default : 3 Result codes: OK Options: AT\N0 Selects Normal (speed buffering) mode. This option takes effect at physical connection time. Same as AT&Q6. AT\N1 Selects serial interface (direct) mode. Same as AT&Q0. AT\N2 Selects reliable link (error correction) mode. This defines the modem-to-modem connection to require error correction. If an attempt to establish the reliable link fails, the modem disconnects. This command takes effect at physical connection time only. To establish MNP-4 after a physical connection, use the AT\O, AT\U, or AT\Y command. AT\N3 Selects auto-reliable link mode. The modem will attempt an error-correction connection but will fallback to Normal mode if unable to establish an MNP-4 link. This command takes effect at physical connection time only. AT\N4 Forces LAPM error correction only. Same as AT\N3S36=0. AT\N5 Forces MNP-4 error correction only. To establish MNP-4 after a physical connection, use the AT\O, AT\U, or AT\Y command. See also: "AT&Qn" "AT\O" "AT\U" "AT\Y"
AT\0 Originate MNP Reliable Link Mode Request Forces the modem to originate an MNP-4 connection regardless of whether the modem is in originate or answer mode. The modem will send up to two link requests. If the modem does not respond after the second request, the modem returns to its previous state. This command can be executed only if a physical connection exists, and will return the NO CARRIER message if there is no connection, or an appropriate connect message if a reliable link connection already exists. This command must be the last command on the command line. Parameters : None Default : None.
AT\Tn Set Inactivity Timer (Modem disconnects if no activity in time n) Determines the length in 1-minute intervals that the modem will wait before disconnecting when no data is sent or received. Any data transmitted or received by the modem will reset the timer. The inactivity timer is inoperative in synchronous mode and in direct mode. Parameters : n = 0-42 (If n>42, 42 is used.) Default : 0 Result codes: OK Options: AT\Tn=0 Disables Timer AT\Tn=1 to 42 Modem disconnects after n minutes without activity
AT\U Accept MNP Reliable Request (request must occur within 12 seconds) Causes the modem to wait up to 12 seconds for a link request from the remote modem to establish an MNP-4 link, regardless of whether the modem is in original or answer mode. If the link request is not received within the time period, the modem returns to its previous state. This command can be executed only if a physical connection exists, and will return the NO CARRIER message if there is no connection, or an appropriate connect message if a reliable link connection already exists. This command must be the last command in the command line. Parameters : none Default : none See also "AT\Kn" "AT&Qn" "AT\O" "AT\Y"
AT\Y Switch To MNP Reliable Mode Causes the modem to establish a reliable link. Depending on whether the modem is in originate or answer mode, the modem either accepts a link request from the remote modem or sends a link request, respectively. If the MNP-4 connection attempt fails, the modem return to its previous state. This command can be executed only if a physical connection exists, and will return NO CARRIER if there is no connection, or an appropriate connect message if a reliable link connection already exists. This command must be the last command on the command line. Parameters : none Default : none See also "AT\Kn" "AT&Qn" "AT\O" "AT\U"
AT\Z Switch From MNP To Normal Mode Causes the modem to switch to the normal mode after a reliable link is established. Switching to normal mode erases any data that may be in the terminal and modem buffers. This command can be executed only if an MNP-4 connection exists, and will return the NO CARRIER message if there is no connection, or an appropriate connect message if a reliable link connection previously existed. This command must be the last command on a command line. Parameters : none Default : none
AT%Cn Compression Control Determines whether or not the modem will use data compression. Parameters : 0 thru 3 Default : 3 Result codes: OK for 0 to 3 ERROR otherwise Options: AT%C0 = Disable all data compression AT%C1 = Enable MNP5 only data compression AT%C2 = Enable V.42bis (BTLZ) only data compression AT%C3 = Enable both MNP5 and V.42bis data compression
AT%Dn Set Dictionary Size (V.42bis) Sets the V.42bis dictionary size. Parameters : 0-3 Default : 2 Result codes: OK Options: AT%D0 = 512 AT%D1 = 1024 AT%D2 = 2048 AT%D3 = 4096 for one-way compression (if AT%M1 or AT%M2 is set). AT%D3 = 2048 for two-way compression (if AT%M3 is set). See also: "AT%Mn"
AT%En Enable/Disable Auto-Retrain & Fallback/Fall Forward Determine whether or not the modem automatically will monitor the line quality and requests a retrain when necessary during a 14400, 12000, 9600, 4800, or 2400 bps connection. Parameters : n = 0-3 Default : 0 Result codes: OK for 0-3 ERROR otherwise Options: AT%E0 = Disable line-quality monitoring & auto-retraining AT%E1 = Enable monitoring & retraining AT%E2 = Enable monitoring & fallback/fall forward AT%E3 = Enable monitoring, retraining, & fast hang-up
AT%L Report Received Signal Level (at connection to DSP) Returns a value identifying the received signal level. The possible values are: 009 Received level of -9 dBm 010 Received level of -10 dBm 011 Received level of -11 dBm . . . 043 Received level of -43 dBm If the received signal is greater than -9 dBm, 009 will be reported. If the received signal is less than -43 dBm, 043 will be reported. Parameters : none Default : none Result codes: OK
AT%Mn Set One/Two-Way Compression Modem (V.42 bis) Selects the one/two way compression mode when using V.42bis compression. Parameters : 0-3 Default : 3 Options: AT%M0 Compression disabled AT%M1 Transmit compression only AT%M2 Receive compression only AT%M3 Two-way compression See also: "AT%Dn"
AT%P Clear V.42 bis Encoder Dictionary Resets the local modem V.42 bis encoder dictionary and sends a command code to the remote modem to reset the remote V.42 bis dictionary. Parameters : none Default : none Result codes: OK If encoder dictionary is in use ERROR If the encoder dictionary is not in use
AT%Q Report Line Signal Quality Returns the high-order byte of the calculated Eye Quality Monitor (EQM) value. The high-order byte can range from 0 to 255. However, when the value is 8 or greater, the modem will automatically retrain if enabled by the AT%E1-3 command. The value for the normal connection ranges from about 0 to 2 and approaches 8 for a progressively poorer connection. Note: Supra modems may be different (see below). Parameters : none Default : none Result codes: OK Reports (per information from Supra): 1 to 8 = current signal quality excellent (higher rate may be used) 9 to 20 = current signal good (best carrier rate for line condition) 20 to 30 = current signal poor (lower carrier rate should be used) 31 to 127 = signal very bad (or gone), try forcing a lower rate NOTE: Modem uses 8 and 20 as rate renegotiation watermarks. Q. How exactly do you use the AT commands %L (received signal level) and %Q (line signal quality)? I can execute them when I'm not on line but how would I execute them when I am on line? A. Once connected, enter +++ (without an Enter) to escape out. You will get an OK prompt, but still be connected. Now enter AT%L%Q to get both reports, (use A/ withouta few times to repeat, as the numbers vary slightly). Enter ATOn to go back online.
AT%Sn Set Maximum BTLZ String Length (V.42 bis) Sets the maximum number of characters that can be compressed into one word. Parameters : 6-250 Default : 32 characters
AT*Hn Link Negotiation Speed (MNP 10) *H0 Link negotiation occurs at highest supported rate (Default) *H1 Link negotiation occurs at 1200 bps. *H2 Link negotiation occurs at 4800 bps.
AT#CID=n Enable/Disable Caller ID Mode Parameters: 0-2 Default: 0 Result code syntax is as follows: DATE=MMDD (where MM is month number 01-12 & DD is day 01-31) TIME=HHMM (where HH is hour 00-23 & MM is minute 00-59) "Single Page Mode": NMBR= number code or statement* *The NUMBER CODE is normally either the subscriber's area code, local exchange, and subscriber loop number, OR a code unique to that individual subscriber. STATEMENT are used for calls from non-Caller ID Areas and subscribers requesting no display. NAME= listed subscriber name (this is an option not always supported) "Multiple Page Mode": MESG= formatted number string** *Here is an example string: 030A35303339363732343030 The string uses this code: CCLL^D^D^D^D^D^D^D^D^D^D... CC (03) is the code meaning this is "Multiple Page" Caller ID AT#CID=n Enable/Disable Caller ID Mode (continued) LL is the hexadecimal length of the data in the string. (in this case 0A hex - 10 decimal) ^D is the formatted data where the first digit is always a number "3" and the second digit is the data, so the string 030A35303339363732343030 converts to 5039672400 **At the time of this printing, conversion of "Multiple Page" Caller ID strings are not supported in the modem, so the data is displayed in the raw format. Options: AT#CID=0 Disable Caller ID (Default) AT#CID=1 Enable Formatted Caller ID Mode AT#CID=2 Enable Raw (ASCII printable HEX number) Mode AT#CID=? Returns Caller ID Modes supported. AT#CID? Displays current Caller ID mode (0-2)
AT)M Cellular Power Level Adjustments (MNP 10) )M0 Power not adjusted during MNP 10 link negotiation (Default) )M1 Power level adjusted during MNP 10 link negotiation.
@Mn MNP-10 Power Level (0-1)
S Registers: S0 Number of Rings to Auto Answer (0 to 255) (0 is disable & default) S1 Number of Rings before last answer. S2 Escape Code character (0 to 255) (default is 43 "+") S3 Carriage Return character (0-127) (default is 13) S4 Line Feed character (0-127) (default is 10) S5 Backspace character (0-32) (default is 8) S6 Time to Wait before Blind Dial (2-255 seconds) (default is 2) (Applies only in X,X1, or X3 dialing mode) S7 Time to Wait for Carrier (1-255 seconds) (default is 50) S8 Pause Time for Comma Dial Command (0-255 seconds) (default is 2) S9 Time to Wait Before Recognizing Carrier (1-255 1/10 seconds) (Default is 6) S10 Delay from Lost Carrier to Hang Up (1-255 1/10 seconds) (Default is 14) S11 DTMF Tone Duration/Spacing (35 to 102 1/100 seconds) (Default is 95) S12 Escape Code Guard Time (0 to 255 1/50 seconds) (0 to disable, the default is 50) S13 Reserved S14 Bit Mapped Option Status Codes: Bit(Dec) 0 (1) Reserved 1 (2) Command echo (En): 0 Disabled (E0) 1 Enabled (E1 default) 2 (4) Quiet Mode (Qn): 0 Send result codes (Q0 default) 1 No result codes (Q1) 3 (8) Result codes (Vn): 0 Numeric (V0) 1 Verbose (V1 default) 4 (16) Reserved 5 (32) Dial Mode: 0 Tone (T default) 1 Pulse (P) 6 (64) Reserved 7 (128) Carrier Mode: 0 Answer 1 Originate S15 Reserved S16 Diagnostic Test Mode setting -Bit Mapped (default 0): 0 &T1 0 = Disable 1 = Enable 1 Not Use 2 &T3 0 = Disable 1 = Enable 3 &T4/&T5 0 = Off 1 = In progress 4 &T6 0 = Disable 1 = Enable 5 &T7 0 = Disable 1 = Enable 6 &T8 0 = Disable 1 = Enable 7 Not Used S17 Reserved S18 Test Mode Timer (0-255 seconds, 0=Runs endlessly) S19 Reserved S20 Reserved S21 Bit Mapped Option Status Codes: Bit(Dec) 0 (1) Set by &Jn command but ignored otherwise: 0 &J0 (default) 1 &J1 1 (2) Reserved 2 (4) CTS Mode (&Rn): 0 CTS always on (&R0) 1 CTS follows RTS (&R1 default) 3 (8) & 4 (16) DTR behavior (&Dn): 0,0 &D0 (default) 1,0 &D1 0,1 &D2 1,1 &D3 5 (32) DCD (RLSD) behavior (&Cn): 0 &C0 (Default) 1 &C1 6 (64) DSR behavior (&Sn): 0 &S0 (Default) 1 &S1 7 (128) Long space diconnect (Yn): 0 Y0 (Default) 1 Y1 S22 Bit Mapped Option Status Codes: Bit(Dec) 0 (1) & 1 (2) Speaker volume (Ln): 0,0 Low (L0) 1,0 Low (L1) 0,1 Medium (L2 default) 1,1 High (L3) 2 (4) & 3 (8) Speaker control (Mn): 0,0 Disabled (M0) 1,0 On until carrier (M1 default) 0,1 ON Always (M2) 1,1 On during handshake (M3) 4 (16), 5 (32), & 6 (64) Dialing Mode / Result Codes (Xn): 0,0,0 X0 1,0,0 Reserved 0,1,0 Reserved 1,1,0 Reserved 0,0,1 X1 1,0,1 X2 0,1,1 X3 1,1,1 X4 (Default) 7 (128) Reserved S23 Bit Mapped Option Status Codes: Bit(Dec) 0 (1) Grant RDL: 0 RDL not allowed (&T5) 1 RDL allowed (&T4 default) 1 (2), 2 (4), & 3 (8) Assumed DTE Rate: 0,0,0 0-300 bps 1,0,0 600 bps 0,1,0 1200 bps 1,1,0 2400 bps (Default) 0,0,1 4800 bps 1,0,1 9600 bps 0,1,1 19200 bps 1,1,1 Reserved 4 (16) & 5 (32) Assumed DTE parity: 0,0 Even 1,0 Reserved 0,1 Odd 1,1 None (default) 6 (64) & 7 (128) Guard tone (&Gn): 0,0 None (&G0 Default) 1,0 550 Hz (&G1) 0,1 1800 Hz (&G2) 1,1 Reserved S24 Sleep Inactivity Timer (0-255 seconds, 0 = default/disable). Defines the number of seconds before modem enters sleep mode without either DTE or phone line activity. S25 Delay to DTR (0-255 1/100 seconds, 5 = default) S26 RTS/CTS Delay (0-255 1/100 seconds, 1 default) (Sync mode only) S27 Bit Mapped Option Status: Bit(Dec) 0 (1), 1 (2), 3 (8) Sync/Async Mode Selection (&Mn/&Qn): 0,0,0 &M0/&Q0 1,0,0 &M1/&Q1 0,1,0 &M2/&Q2 1,1,0 &M3/&Q3 0,0,1 &Q4 1,0,1 &Q5 (Default) 0,1,1 &Q6 2 (4) Leased line control (&Ln): 0 Dial-up line (&L0 default) 1 Leased line (&L1) 4 (16) & 5 (32) Internal Sync clock select (&Xn): 0,0 Internal (&X0 default) 1,0 External (&X1) 0,1 Slave (&X2) 6 (64) CCITT/Bell Mode (Bn): 0 CCITT (B0) 1 Bell (B1 US default) 7 (128) Reserved S28 Bit Mapped Options Bit(Dec) 0 (1) V.23 split screen (\Wn): 0 Disabled (\W0 default) 1 Enabled (\W1) 1 (2) V.23 split screen direction: 0 75Tx (%F0 default) 1 1200Tx (%F1 default) 2 (4) V.23 half-duplex: 0 Disabled 1 Enabled (%F3) 3 (8) & 4 (16) Pulse dialing mode (&Pn): 0,0 &P0 (Default) 1,0 &P1 0,1 &P2 1,1 &P3 5 (32) Reserved 6 (64) Reserved 7 (128) Reserved S29 Flash Dial Modifier Time S30 Inactivity Timer (0-255 Unit 10 seconds, 0=disable/default) In Reliable mode any data transfer resets timer. In Normal mode only sent data resets timer. S31 Bit Mapped Options: Bit(Dec) 0 (1) Reserved 1 (2) Auto Mode Selection: 0 Disabled (N0) 1 Enabled (N1 default) 2 (4), 3 (8) Error Correction Result Code (Wn): 0,0 DTE Speed only (W0 default) 1,0 Full Reporting (W1) 0,1 DCE Speed only (W2) 4 (16) Reserved 5 (32) Reserved 6 (64) Reserved 7 (128) Reserved S32 XON Character (0-255, Default 17) S33 XOFF Character (0-255, Default 19) S36 Negotiation Failure Treatment (0-7 7 is default): Fallback options when S48=128 or error correction link fails: 0 Disconnect 1 Establish Direct connection 2 Undefined 3 Establish Normal connection 4 Establish a MNP connection if possible, else Disconnect 5 Establish a MNP connection if possible, else Direct connection 6 Undefined 7 Establish a MNP connection if possible, else Normal connection S37 Forced Single Carrier Rate (0-1, 5-12; 0 is default): 0 Carrier Rate at the rate the last AT command was issued. (If rate is above highest carrier rate, then the highest carrier rate the modem supports is used.) 1 300 bps 2-4 Undefined 5 1200 bps 6 2400 bps 7 1200/75 bps (v.23 mode) 8 4800 bps 9 9600 bps 10 12000 bps 11 14400 bps 12 7200 bps S38 Delay Before Forced Disconnect (0-255 seconds, default 20): 0-254 Delay in seconds from H command, or DTR toggle ON or OFF (if modem is set to follow DTR), before modem disconnects. 255 Modem send data out of buffer until completed or connection is lost. S40 Bit Mapped Option Status Codes: Bit(Dec) 0 (1) MNP Extended Services (-Kn): 0 Disable (-K0) 1 Enable (-K1) 1 (2) Power Level Adj. for Cellular Use [)Mn]: 0 Auto Adj. [)M0 default 1 Force Adj. [)M1] 2 (4) MNP Link negotiation speed (*Hn): 0 At highest rate (*H0 default) 1 At 1200 bps (*H1) 3 (8), 4 (16), & 5 (32) Break Handling (\Kn): 0,0,0 \K0 1,0,0 \K1 0,1,0 \K2 1,1,0 \K3 0,0,1 \K4 1,0,1 \K5 6 (64) & 7 (128) MNP Block size (\An): 0,0 64 (\A0) 1,0 128 (\A1) 0,1 196 (\A2) 1,1 256 (\A3) S41 Bit Mapped Option Status Codes: Bit(Dec) 0 (1) & 1 (2) Compression Selection (%Cn): 0,0 Disabled (%C0) 1,0 MNP 5 (%C1) 0,1 V.42bis (%C2) 1,1 MNP 5 & V.42bis (%C3) 2 (4) Auto Retrain (%En): 0 Disable (%E0 default) 1 Enable (%E1) 3 (8) Modem to Modem Flow Control (\Gn): 0 Disable (\G0 default) 1 Enable (\G1) 4 (16) Block mode control (\Ln): 0 Stream (\L0 default) 1 Block (\L1) 5 (32) Reserved 6 (64) Reserved 7 (128) Reserved S46 Protocol Selection (136 or 138) (Affects v.42/v.42bis mode): 136 Disable Compression 138 Enable Compression (default) S48 v.42 Negotiation (0,7,128): 0 Disable Negotiation, proceed with LAPM 7 Enable Negotiation (default) 128 Disable Negotiation, fallback per S36 setting S82 LAPM Break Handling Options (3,7,128): 3 Expedited: Modem sends break immediately & data integrity is maintained before and after break. 7 Destructive: Modem sends break immediately & data being processed by each modem at that time is destroyed. 128 In sequence: Modem sends break in sequence with transmitted data. Data integrity is maintained before and after the break. S86 Report Connection Failure Cause Code: 0 Normal disconnect 1-3 Undefined Error Code 4 Carrier loss 5 No error correction at other end 6 No response to feature negotiation 7 This modem is ASYNC only, other is SYNC 8 No framing technique in common 9 No protocol in common 10 Bad response to feature negotiation 11 No sync information from remote 12 Normal hangup initiated by remote 13 Retransmission limit reached 14 Protocol violation occured 15-255 Undefined Error Code S95 Extended Result Code Control (default sum is 0) Each bit set high in this register enables the corresponding result code regardless of the W command setting. Bit (Decimal Value): 0 (1) CONNECT XXXX result code gives DCE to DCE rate instead of local DTE to DCE rate. 1 (2) Append /ARQ to verbose CONNECT result code if protocol is NONE 2 (4) Enable CARRIER XXXX result code 3 (8) Enable PROTOCOL XXXX result code 4 (16) Undefined 5 (32) Enable COMPRESSION result code 6 (64) Undefined 7 (128) Undefined S109 v.32/v.32bis Negotiation Rate Selection (default sum is 62) Each bit set high in this register enables the corresponding rate as a valid rate to be used during rate negotiation. Bit (Decimal Value): 0 (1) Unused 1 (2) 4800 bps 2 (4) 7200 bps 3 (8) 9600 bps 4 (16) 12000 bps 5 (32) 14400 bps 6 (64) Unused 7 (128) Unused S110 v.32/v.32bis Mode & Rate Negotiation Control: 0 Normal v.32 mode (no v.32bis support) 1 Normal v.32bis mode 2 v.32bis mode with automatic rate renegotiation (default) 3 v.32bis mode with automatic rate renegotiation starting with the lowest rate set in S109 and working up one defined rate at a time toward the highest rate set in S109 (based on %Q level at each rate prior to stepping up.) (If the modem steps back down, it will also follow the S109 settings.) SCn=n BUSY Detect Watermark Controls Each register "pair" holds the value for each setting. To set a value, divide the setting by 256. The integer goes in the second register, while the remained goes in the first. (A setting of 516 would convert to 2 Remainder 4, and could be set by sending ATSC0=4SC1=2 to the modem.) Settings are in 1/100ths of a second. Default values: Minimum BUSY ON Time: SC0=30 SC1=0 Maximum BUSY ON Time: SC2=75 SC3=0 Minimum BUSY OFF Time: SC4=30 SC5=0 Maximum BUSY OFF Time: SC6=75 SC7=0 (Defaults support FCC Spec. BUSY signal. Setting SC0=25 & SC4=25 allows FAST BUSY to also be detected as BUSY.) SC8=n Set number of valid BUSY Pulses before reporting BUSY (4 is default) End of S-Register Information
Modem Connection Result Codes: Numeric Verbose 0 OK 1 CONNECT (300 bps) 2 RING 3 NO CARRIER 4 ERROR 5 CONNECT 1200 6 NO DIALTONE 7 BUSY 8 NO ANSWER 9 CONNECT 0600 10 CONNECT 2400 11 CONNECT 4800 12 CONNECT 9600 13 CONNECT 7200 14 CONNECT 12000 15 CONNECT 14400 16 CONNECT 19200 17 CONNECT 38400 18 CONNECT 57600 19 CONNECT 115200 (Not Currently Supported on MOST models) 22 CONNECT 1200/75 (Models with v.23 support only) 23 CONNECT 75/1200 (Models with v.23 support only) 24 DELAYED 32 BLACKLISTED 33 FAX 35 DATA 40 CARRIER 300 44 CARRIER 1200/75 (Models with v.23 support only) 45 CARRIER 75/1200 (Models with v.23 support only) 46 CARRIER 1200 47 CARRIER 2400 48 CARRIER 4800 49 CARRIER 7200 50 CARRIER 9600 51 CARRIER 12000 52 CARRIER 14400 66 COMPRESSION: CLASS 5 (MNP 5) 67 COMPRESSION: V.42BIS (BTLZ) 69 COMPRESSION: NONE 70 PROTOCOL: NONE 77 PROTOCOL: LAP-M (V.42) 80 PROTOCOL: ALT (MNP) 81 PROTOCOL: ALT - CELLULAR (MNP 10) +FC +FCERROR SupraModem Encoded Optional Feature List (ATI10) These codes are being added to SupraFAXModem ROMs, but in some cases not all codes have been added that are supported by a given product, and codes have been assigned for features not yet available:. Code Feature Functions/Commands/Codes Added 101 Fax CLASS 1 Normal CLASS 1 FAX Command Set 104 Fax CLASS 2 Normal CLASS 2 FAX Command Set 105 Fax CLASS 2.0 Normal CLASS 2.0 FAX Command Set 115 CCITT v.17 (14.4 Fax) Adds 12k & 14.4k fax operation 140 CCITT v.32bis (14.4 Data) Adds 7200, 12k, & 14.k carriers 141 Silent Answer +FAE=n +FAA=n > CLASS 2 units only < 142 Caller ID #CID=n 143 MNP 10 -B Forced FB to 1200 -C MNP10 Sync Mode -C1 MNP10 Async Mode -C2 MNP 2 -C3 MNP 3 -K No LAPM to MNP10 Conv. -K1 Conv. LAPM to MNP10 -Q FB to v.22/v.22bis -Q1 No FB to v.22/v.22bis -Un Tx Level Change during FF -U0 auto attn to -10dBm -U1 auto attn to -18dBm -U2 auto attn to -22dBm -U3 auto attn to -25dBm -U4 Force 2400 to -10dBm -U5 Force 2400 to -18dBm -U6 Force 2400 to -22dBm -U7 Force 2400 to -25dBm )M Tx fixed at -10dBm )M1 Tx attempt Tx < -10dBm *H0 Link Neg. at Top Speed *H1 Link Neg. at 1200 *H2 Link Neg. at 4800 144 MNP "Cellular" In Docs if a Supported Feature 145 AutoSync In Docs if a Supported Feature 160 Programable Voice In Docs if a Supported Feature 161 ADPCM In Docs if a Supported Feature 162 MACE In Docs if a Supported Feature *** SUPRA WARNING *** The following commands are accepted by some models, but are ONLY for internal use at Supra. (Supra's staff cannot assist you in regard to these commands, and under no case should you attempt use or adjust these settings.): ATS91=x ATS92=x ATS99=x AT!(x) These commands are quite powerful and can cause unpredictable or total lack of operation. (In many cases, service at Supra would be required to restore normal operation.) ---------------- END DATA MODEM COMMAND DESCRIPTIONS ------------------- FAX COMMANDS FOR THE ROCKWELL CHIP SET 6/19/92 The following information has been taken from Rockwell's RC144AC manual. It has not been taken from the CCITT Class 1 documentation, which is copyrighted by the CCITT. This information is provided for educational purposes only. To fully understand this information requires a through knowledge of the T.4 fax image and the T.30 fax session protocol standards. We STRONGLY urge anyone attempting to develop fax software to get the required documentation from Global Engineering or the TIA. A SHORT HISTORY OF CLASS 1 AND 2 In 1988 the CCITT TR29.2 committee accepted the Class 1 standard for communication between fax software and fax modems. The committee also voted on, but did not accept for various technical reasons, the Class 2 standard. A year later, they had slightly revised the standard but again did not accept it. Software and hardware manufacturers decided to unofficially adopt this standard until the TR29.2 committee could develop an acceptable standard. Since so many companies have used the unofficial standard, the TR29.2 committee has designated that when the standard is officially adopted it will be known as Class 2.0. Over the last year or so, the TR29.2 committee has voted on several revisions to the Class 2 standard. Their last vote was early May '92. A no vote for technical reasons was entered. The TR29.2 committee is now reviewing the technical issues that were raised. As of June, 1992 a projected date for the next ballot has not been given. WHAT IS THE DIFFERENCE BETWEEN CLASS 1 AND 2? Class 1 fax software handles all of the T.4 fax image and T.30 session protocol information and timing. Thus, the ability to communicate properly with various fax machines is more a function of the software than the fax modem. Class 2 fax software generates a T.4 fax page image and sends it to the fax modem a page at a time. The fax modem then handles the T.30 session protocol information and timing. This relieves the computer's cpu from some work. The ability to communicate properly with various fax machines is more a function of the fax modem than the software. However, to further complicate matters, class 2 fax software can issue Class 1 commands and take over some of the duties of the Class 2 fax modem. When users have a problem communicating correctly with a fax machine/modem, it can be very difficult to determine which is at fault, the software or the hardware. Please remember that there are issues that have not been addressed or settled by the TR29.2 committee in the Class 2 specifications. (i.e. how the DCD and DTR lines are handled while in fax mode.) WHERE TO GET OFFICIAL FAX DOCUMENTATION Telecommunications Industry Association 1722 Eye St. NW Suite 440 Washington, DC 20006 You need to ask for: Class 1 documentation - EIA/TIA-578 Class 2 documentation - Electronic Industries Association and Telecommunications Industry Association TIA Project Number 2388, Asynchronous Facsimile DCE Control Standard, Service Class 2, TR-29.2 Committee Letter Ballot Global Engineering Documents 2805 McGaw Ave Irvine, CA 92713 800-854-7179 714-261-1455 714-261-7892 (Fax) You need to ask for: EIA/TIA-578 - Class 1 documentation EIA/TIA-592 - Class 2 documentation CCITT v7.3 - T.1 - T.90 standards, includes T.4 & T.30 (In 1992 the cost for the above docs ran close to $200. But Global will also update you on any changes or additions to those standards you purchase.) Global Engineering will not have the Class 2 documentation until approximately a month after the TR29.2 committee accepts it. Most of those companies which have developed Class 2 fax software either sit on the TR29.2 committee or know someone who does. It may be possible to receive the documentation from the TIA if you present a credible proposal. CLASS 1 FAX COMMANDS FOR FAXMODEMS FAX CLASS 1 OPERATION FAX I/O PROCESSING The fax I/O interface supports asynchronous serial and parallel interfaces. The interface rate is 19200 bps. Start and stop elements are removed from the transmit data and added to the receive data. Both transmit and receive data is buffered. Flow control using XON/XOFF (DC1/DC3) or RTS/CTS is provided. Unique control character strings are identified, filtered, or reinserted into the I/O data stream. These control characters and their resultant action are described below. DTE TO MODEM TRANSMIT DATA STREAM Characters Detected Action takenDelete characters Recognize as a string terminator, and take appropriate action Replace with single character MODEM TO DTE RECEIVE DATA STREAM Characters Detected Action taken Insert extra ahead of The modem also identifies the end of a frame by inserting into the data stream after the FCS bytes. FAX MODE SELECTION Fax class 1 commands are identified in Table 1-1 & defined in Table 1-2. Fax modes and rates are determined by the AT+F commands as described in Table 1-2. FAX ORIGINATION Origination of fax calls is made using the ATD command. Upon completion of the dial function, a calling tone at 1100 Hz, with a cadence of 0.5 seconds ON, and 3 seconds off is transmitted. The modem automatically enters mode +FRH=3 and sends the CONNECT message to the DTE when FSK flags are detected from the remote. FAX ANSWERING Answering of fax calls is identical to answering of data calls with the exception that the modem enters the fax handshaking mode instead of the data handshaking mode after going off-hook. If +FAE=0, the modem, after sending answer tone, automatically enters fax mode (+FTH=3), sends the CONNECT message to the DTE, and starts sending FSK flags. If +FAE=1, the modem determines if the caller is a data modem or fax modem and sends the DATA or FAX result code, respectively, to the DTE. Table 1-1. Fax Class 1 Commands ----------------------------------------------------------- | Command Function | |---------------------------------------------------------| | SERVICE CLASS ID | |---------------------------------------------------------| | +FCLASS= Service Class | |---------------------------------------------------------| | FAX CLASS 1 COMMANDS | |---------------------------------------------------------| | +FTS=n Stop Transmission and Wait | | +FRS=n Receive Silence | | +FTM=n Transmit Data | | +FRM=n Receive Data | | +FTH=n Transmit Data with HDLC Framing | | +FRH=n Receive Data with HDLC Framing | |---------------------------------------------------------| FAX CONTROL TRANSMISSION Fax control transmission is initiated by the AT+FTH=n command. After this command is issued, the modem generates the CONNECT message and transmits carrier in the modulation scheme specified by the parameter n. The modem then transmits HDLC flags for a minimum of 1 second. The modem continues to transmit the HDLC flags until it receives a character from the DTE. When characters are received from the DTE, the modem adds start and end flags, performs zero-bit insertion, generates FCS, and deletes character pairs before transmitting the characters to the remote fax machine. Each sequence is transmitted as a single . is considered as the end of frame marker and is not transmitted. All data received from the DTE afar is ignored by the modem until the modem generates either the CONNECT, OK, or ERROR result code. If no more data is in the transmit buffer and the final bit was a 1 (bit 4 of the second byte received from the DTE), the modem generates the OK result code and returns to the command mode. If the final bit was a 0, the modem generates the CONNECT message and waits for further data from the DTE while transmitting HDLC flags. If no more data is received before 5 seconds elapse, the modem drops carrier, goes on-hook, and generates the ERROR result code. FAX CONTROL RECEPTION Fax control reception is initiated using the AT+FRH=n command. After this command is issued, the modem looks for carrier in the modulation scheme specified by the parameter n. If no carrier is detected before the period of time specified by register S7 expires, the modem generates the NO CARRIER message and returns to command mode. If carrier is detected that is not the one specified by the parameter n, the modem generates the +FCERROR message and returns to the command mode. If the specified carrier is detected, the modem generates the CONNECT message and enters the HDLC receive mode. In HDLC receive mode, the modem receives HDLC frames from the remote fax machine, strips the flags, performs zero-bit deletion, performs error checking, and handles character pairs before passing the data to the DTE. The modem prefixes each character with another character before sending it to the DTE. After the last byte in the frame, the modem sends to the DTE marking the end of the frame. The modem then generates either the OK message if errors were detected (FCS is incorrect), and returns to command mode. While in command mode, the modem continues to receive data in the selected modulation scheme, and sends the data after sending the CONNECT message to the DTE when the DTE reissues the +FRH command with the same parameter. If the DTE issues the +FRH command with a different parameter, the modem clears all buffers and proceeds as described previously. If carrier is lost while in command mode and the DTE reissues the +FRH command with the same parameter, and there is no data in the buffer, the modem sends the ERROR result code to the DTE and returns to the command mode. If there is data in the buffer, the modem sends the next frame of buffered data to the DTE, followed by , and either the ERROR result code if errors were detected or the OK result code if no errors were detected. The modem then returns to command mode. The modem concludes an error is detected if the carrier is lost for any period of time during or before the reception of a frame. If carrier is lost for a time period longer than the time specified by the register S10, the modem finishes delivering the data in the receive buffer (if any) to the DTE, sends , generates the ERROR message, and returns to command mode. All subsequent data received from the remote is discarded. If the modem detects a frame abort sequence (seven consecutive ones with no zero insertion) while it is waiting for a frame beginning flag (it was receiving HDLC flags), it will wait for the HDLC flags again until either carrier is lost, or the DTE aborts the process by sending an abort character or by dropping DTR with &D2 in effect. If the frame abort sequence is detected while the modem is receiving a frame it finishes delivering the data in the receive buffer (if any) to the DTE, sends , generates the ERROR message, and returns to command mode. The modem keeps looking for HDLC flags followed by more data from the remote, with the selected modulation scheme. If the modem detects a receive buffer overflow condition, it concludes that there was a FCS error in that frame. The modem will receive more frames only if a starting flag is detected and there is room in the receive buffer. If a starting flag is detected and there is no room in the buffer, the modem discards all data in that frame. If the modem receives any character from the DTE after the +FRH command (except flow control characters if software flow control is in effect), or if the modem detects a high-to-low transition of the DTR signal while &D1 is in effect, it sends to the DTE, generates OK result code, and returns to command mode. The receive buffer is cleared and all data received from the remote is discarded. If the modem detects a DTR drops while &D2 is in effect, it goes on-hook, sends to the DTE, generates OK result code, and returns to command mode. If the modem detects a DTR drop while &D3 is in effect, the modem performs a warm reset. FAX DATA TRANSMISSION Fax Data transmission is initiated by the AT+FTM=n command. After this command is issued, the modem generates the CONNECT message and transmits carrier in the modulation scheme specified by the parameter n. The modem then transmits constant 1 bits for a minimum of one second and continues to transmit constant 1 bits until it receives a character from the DTE. When data is received from the DTE, the modem deletes start and stop bits and deletes all character pairs before transmitting the data to the remote. Each sequence is transmitted as a single . is considered as the end of stream marker, and is not transmitted. All data received from the DTE after the is ignored by the modem until the modem generates either the CONNECT, OK or ERROR result code. If no more data is in the transmit buffer, and the last transmitted character was not an ASCII NULL, the modem generates the OK result code and returns to the command mode. If the last character transmitted was an ASCII NULL, the modem generates the CONNECT message to the DTE and waits for further data from the DTE while transmitting NULLs to the remote. If more data is received before five seconds, elapse, the modem continues to transmit the data as described in the previous paragraph. If five seconds elapse and no data is received from the DTE, the modem drops carrier, goes on-hook, and generates the ERROR result code. FAX DATA RECEPTION Fax data reception is initiated using the AT+FRM=n command. After this command is issued, the modem looks for carrier in the modulation scheme specified by the parameter n. If no carrier is detected before the period of time specified by register S7 expires, the modem generates the NO CARRIER message and returns to command mode. If carrier is detected that is not the one specified by the parameter n, the modem generates the +FCERROR message and returns to the command mode. If the specified carrier is detected, the modem generates the CONNECT message and enters the data receive mode. While in data receive mode, the modem receives data from the remote, adds start and stop bits, and handles character pairs before passing the data to the DTE. The modem prefixes each character with another character before sending it to the DTE. If carrier is lost for a time period longer than the time specified by the register S10, the modem finishes delivering the data in the receive buffer (if any) to the DTE, sends , generates the NO CARRIER result code, and returns to the command mode. All subsequent data received from the remote is discarded. If the modem detects a receive buffer overflow condition, it stops receiving from the remote until there is room in the receive buffer. The modem informs the DTE of the buffer overflow after it sends to the DTE the last character that was stored in the buffer before the overflow occurred. If the modem receives any character from the DTE after the +FRM command (except flow control characters if software flow control is in effect), or if the modem detects a high-to-low transition of the DTR signal while &D1 is in effect, it sends to the DTE, generates the OK result code, and returns to command mode. The receive buffer is cleared and all data received from the remote is discarded. If loss of DTR is detected while &D2 is in effect, the modem goes on-hook, sends followed by OK result code to the DTE, and returns to command mode. If the modem detects a DTR drop while &D3 is in effect, the modem performs a warm reset. EXAMPLES Examples of calling (transmitting) and answering (receiving) one page use fax class 1 commands are shown in Tables 1-3 and 1-4, respectively. Table 1-2. Fax Class 1 Command Definitions Command Description +FCLASS=n Select service class. +FCLASS=n command sets the active service class. Parameters: 0-2 Default: 0 Command options: +FCLASS=0 Select Data Mode +FCLASS=1 Select Facsimile class 1 +FCLASS=2 Select Facsimile class 2 +F ? Report Active Configuration. +F ? interrogates the modem to determine the active configuration. Typical responses are: +FAE? 0 if autoanswer is disabled, 1 if auto answer enabled. +FCLASS? 0 if in data mode; 1 if in fax class 1; 2 if in fax class 2 +F =? Report Operating Capabilities. +F =? can be used to determine the operating capabilities of the modem. Typical responses are: +FAE=? 0,1 +FCLASS=? 0,1,2 +FTM=? 3,24,48,72,96 (RC96AC) +FRM=? 3,24,48,72,96 (RC96AC) +FTM=? 3,24,48,72,73,74,96,97,98,121,122,145,146 (RC144AC) +FRM=? 3,24,48,72,73,74,96,97,98,121,122,145,146 (RC144AC) Table 1-2. Fax Class 1 Command Definitions (continued) +FAEn Data/Fax Auto Answer. +FAEn allows the DTE to either restrict answering to class 1, or to automatically detect whether the calling station is a fax class 1 modem or data modem,, and answer accordingly. Parameters: 0,1 Default:0 Command options: n=0 Disable data/fax auto answer mode (default). The modem answers as a fax modem only n=1 Enable data/fax auto answer mode. The modem answers as a fax or data modem
Of Special Interest to Supra Users: +FAE=n Adaptive Answer/Silent Answer Mode Control n=0 Disable Both n=1 Adaptive Answer ONLY n=2 Adaptive Answer & Silent Answer n=3 Silent Answer ONLY
+FTS=n Stop Transmission and Wait. +FTS=n causes the modem to terminate a transmission and wait for n 10 millisecond intervals before responding with the OK result code. An ERROR response code results if this command is issued while the modem is on-hook. +FRS=n Receive Silence. +FRS=n causes the modem to report back to the DTE with an OK result code after n millisecond intervals of silence have been detected on the line. This command is aborted if any character is received from the DTE. The modem discards the aborting character and issues an OK result code. An ERROR response code results if this command is issued while the mode is on-hook. Table 1-2. Fax Class 1 Command Definitions (continued) +FTM=n Transmit Data. +FTM=n causes the modem to transmit data using the modulation defined below. An ERROR response code results if this command is issued while the modem is on-hook. Parameters: Command options: +FTM=3 v.21 ch 2 300 bps +FTM=24 v.27 ter 2400 bps +FTM=48 v.27 ter 4800 bps +FTM=72 v.29 7200 bps +FTM=96 v.29 9600 bps +FTM=73 v.17 7200 bps long +FTM=74 v.17 7200 bps short +FTM=96 v.29 9600 bps +FTM=97 v.17 9600 bps long +FTM=98 v.17 9600 bps short +FTM=121 v.17 12000 bps long +FTM=122 v.17 12000 bps short +FTM=145 v.17 14400 bps long +FTM=146 v.17 14400 bps short Table 1-2. Fax Class 1 Command Definitions (continued) +FRM=n Receive Data. +FRM=n causes the modem to enter the receiver mode using the modulation defined below. An ERROR response code results if this command is issued while the modem is on-hook. Parameters: See Command options Command options: +FTM=3 v.21 ch 2 300 bps +FTM=24 v.27 ter 2400 bps +FTM=48 v.27 ter 4800 bps +FTM=72 v.29 7200 bps +FTM=96 v.29 9600 bps +FTM=73 v.17 7200 bps long +FTM=74 v.17 7200 bps short +FTM=96 v.29 9600 bps +FTM=97 v.17 9600 bps long +FTM=98 v.17 9600 bps short +FTM=121 v.17 12000 bps long +FTM=122 v.17 12000 bps short +FTM=145 v.17 14400 bps long +FTM=146 v.17 14400 bps short Table 1-2. Fax Class 1 Command Definitions (continued) +FTH=n Transmit data with HDLC Framing. +FTH=n causes the modem to transmit data using HDLC protocol and the modulation defined below. An ERROR response code results if this command is issued while the modem is on-hook. Parameters: See Command options Command options: +FTM=3 v.21 ch 2 300 bps +FTM=24 v.27 ter 2400 bps +FTM=48 v.27 ter 4800 bps +FTM=72 v.29 7200 bps +FTM=96 v.29 9600 bps +FTM=73 v.17 7200 bps long +FTM=74 v.17 7200 bps short +FTM=96 v.29 9600 bps +FTM=97 v.17 9600 bps long +FTM=98 v.17 9600 bps short +FTM=121 v.17 12000 bps long +FTM=122 v.17 12000 bps short +FTM=145 v.17 14400 bps long +FTM=146 v.17 14400 bps short Table 1-2. Fax Class 1 Command Definitions (continued) +FRH=n Receive data with HDLC Framing. +FRH=n causes the modem to receive frames using HDLC protocol and the modulation defined below. An ERROR response code results if this command is issued while the modem is on-hook. Parameters: See Command options Command options: +FTM=3 v.21 ch 2 300 bps +FTM=24 v.27 ter 2400 bps +FTM=48 v.27 ter 4800 bps +FTM=72 v.29 7200 bps +FTM=96 v.29 9600 bps +FTM=73 v.17 7200 bps long +FTM=74 v.17 7200 bps short +FTM=96 v.29 9600 bps +FTM=97 v.17 9600 bps long +FTM=98 v.17 9600 bps short +FTM=121 v.17 12000 bps long +FTM=122 v.17 12000 bps short +FTM=145 v.17 14400 bps long +FTM=146 v.17 14400 bps short Table 1-3 Fax Class 1 Calling Sequence (One Page) |----------------------------------------------------------------------| | DTE Commands | DCE Responses | Remote Fax | Notes | |--------------|------------------|-----------------|------------------| | AT+FCLASS=1 | OK | | Set to Class 1 | |----------------------------------------------------------------------| | PHASE A | |----------------------------------------------------------------------| | ATDTx | dials | answers | +FRH=3 implied by| | | | | dialing | | | CONNECT | Send HDLC flags | | |----------------------------------------------------------------------| | PHASE B | |----------------------------------------------------------------------| | | | Send NSF frame | | | |,OK | | | | AT+FRH=3 | CONNECT | | | | | | Send CSI frame | | | | ,OK | | | | AT+FRH=3 | CONNECT | | | | | | Send DIS frame | Last frame bit=1 | | | ,OK | drop carrier | | | AT+FTH=3 | Send HDLC flags | receive flags | | | | CONNECT | | | | | Send TSI frame | Receive TSI | Last frame bit=0 | | | CONNECT | | | | | Send DCS frame | Recieve DCS | Last frame bit=1 | | | detect last frame| | | | | bit | | | | | ,drop carrier| | | | AT+FTS=8 | ,wait 80ms | | | | AT+FTM=96 | send v.29 | | | | | CONNECT | | | | | Send TCF data | Receive & check | | | AT+FRH=3 | CONNECT | | | | | Send CFR frame | | Last frame bit=1 | | ,OK | drop carrier | | | | | OK | | | |----------------------------------------------------------------------| | PHASE C | |----------------------------------------------------------------------| | AT+FTM=96 | send v.29 | | | | | CONNECT | | | | age data | send page data | receive data | | | | OK | | | | AT+FTH=3 | send HDLC flags | receive flags | | | | CONNECT | | | |----------------------------------------------------------------------| Table 1-3 Fax Class 1 Calling Sequence (One Page, continued) |----------------------------------------------------------------------| | PHASE D | |----------------------------------------------------------------------| | | send EOP frame | receive EOP | Last frame bit=1 | | | OK,drop carrier | | | | AT+FRH=3 | CONNECT | | | | | | send MCF frame | Last frame bit=1 | | | ,OK | | | | AT+FTH=3 | send HDLC flags | receive flags | | | | CONNECT | | | | | send DCN frame | receive DCN | Last frame bit=1 | | | OK,drop carrier | | | |----------------------------------------------------------------------| | PHASE E | |----------------------------------------------------------------------| | ATH0 | OK,hang up | hang up | | |----------------------------------------------------------------------| Table 1-4 Fax Class 1 Answering Sequence (One Page) |----------------------------------------------------------------------| | DTE Commands | DCE Responses | Remote Fax | Notes | |--------------|------------------|-----------------|------------------| | AT+FCLASS=1 | OK | | | |----------------------------------------------------------------------| | PHASE A | |----------------------------------------------------------------------| | | | Fax machine dial| | | | RING | | | | ATA | modem answers | | | | | send HDLC flags | receive flags | +FTH=3 implied by| | | | | answering | | | CONNECT | | | |----------------------------------------------------------------------| | PHASE B | |----------------------------------------------------------------------| | | send NSF frame | receive NSF | last frame bit=0 | | | CONNECT | | | | | send CSI frame | receive CSI | last frame bit=0 | | | CONNECT | | | | | send DSI frame | receive DSI | last frame bit=1 | | | OK, drop carrier | | | | AT+FRH=3 | CONNECT | | | | | | send TSI frame | last frame bit=0 | | | ,OK | | | | AT+FRH=3 | CONNECT | | | | | | send DCS frame | last frame bit=1 | | | ,OK | drop carrier | | | AT+FRM=96 | | | | | | | send v.29 | | | | CONNECT | send TCF frame | | | | | drop carrier | | | | NO CARRIER | | | | AT+FTH=3 | CONNECT | | | | | send CFR frame | receive CFR | last frame bit=1 | | | OK,drop carrier | | | |----------------------------------------------------------------------| | PHASE C | |----------------------------------------------------------------------| | AT+FRM=96 | | | | | | | send page data | | | | | drop carrier | | | | NO CARRIER | | | |----------------------------------------------------------------------| Table 1-4 Fax Class 1 Answering Sequence (One Page), continued |----------------------------------------------------------------------| | PHASE D | |----------------------------------------------------------------------| | AT+FRH=3 | CONNECT | | | | | | send EOP frame | last frame bit=1 | | | ,OK | | | | AT+FTH=3 | CONNECT | | | | | send MCF frame | receive MCF | last frame bit=1 | | | OK,drop carrier | | | | AT+FRH=3 | CONNECT | | | | | | send DCN frame | last frame bit=1 | | | ,OK | | | |----------------------------------------------------------------------| | PHASE E | |----------------------------------------------------------------------| | ATH0 | OK,hang up | hang up | | |----------------------------------------------------------------------| ---------------- END OF CLASS 1 FAX COMMANDS FOR MODEMS ---------------- CLASS 2 FAX COMMANDS FOR FAXMODEMS ROCKWELL STANDARDS FOR FAX CLASS 2 The following information has been taken from Rockwell's RC144AC manual. It has not been taken from the CCITT Class 2 documentation, which is copyrighted by the CCITT. This information is provided for educational purposes only. To fully understand this information requires a through knowledge of the T.4 fax image and the T.30 fax session protocol standards. While a majority of this information is correct, Rockwell does not imply or warrant that any FaxModem will work exactly as documented here. This information is based on an early draft of Class 2, which has undergone further revisions and changes by the CCITT TR29.2 committee. We STRONGLY urge anyone attempting to develop fax software to get the required documentation from Global Engineering or the TIA. COMMAND SYNTAX AND GUIDELINES DTE COMMANDS The ISO 646 character set (T.50 International Alphabet 5, American Standard Code for Information Interchange) is used for the issuance of commands and responses. Only the low-order 7 bits of each character are used for commands or parameters; the high order bit is ignored. Upper case characters are equivalent to lower case characters. For Phase C data transmission or reception, all 8 bits are needed. DTE COMMAND LINES A command line is a string of characters sent from a DTE to the DCE while the DCE is in a command state. Command lines have a prefix, a body, and a terminator. The prefix consists of the ASCII characters 'AT' (065, 084) or 'at' (097, 116). The body is a string of commands restricted to printable ASCII characters, (032-126). Space characters (ASCII 032) and control characters other than CR (013) and BS (010) in the command string are ignored. The default terminator is the ASCII character. Characters that precede the AT prefix are ignored. BASIC COMMAND SYNTAX Characters within the command line are parsed as commands with associated parameter values. The basic commands consist of single ASCII characters, or single characters preceded by a prefix character (e.g., '&'), followed by a decimal parameter. Missing decimal parameters are evaluated as 0. EXTENDED COMMAND SYNTAX The facsimile commands use extended syntax. They are preceded by the '+F' characters, and they are terminated by the semicolon ';' character (059) or by the that terminated the command line. AT+FAA=0 ;+FCR 1 This command instructs the DCE to answer automatically a data or fax call and also enables reception. AT+FCLASS=0 for data mode AT+FCLASS=1 for Service Class 1 Fax AT+FCLASS=2 for Service Class 2 Fax In Class 2, the DCE makes and terminates calls, manages the communication session and negotiates (T.30 protocol) and transports the image date to DTE. The T.4 protocol management of image data, etc. is done by DTE. The response to AT+FCLASS=0 in Data Mode or AT+FCLASS=2 in Service Class 2 Fax is OK The service class may be set by the DTE from the choices available using the '+FCLASS= ' command. GENERAL RULES 1. +Fnnn commands must be entered completely otherwise an ERROR response is sent. 2. All response messages are preceded and followed by . Multiple response commands, e.g., +FDIS:+FCSI: and +FDCS, will therefore appear to a have a blank line between them. 3. Fax Class 2 commands can be separated by the ";" character. The ";" can be omitted if desired. Note that non-data commands cannot be separated by ";" which is allowed as a dial modifier. 4. All class 2 commands are assumed to be the final command on a command line. Additional characters will be ignored. 5. An ERROR message will be generated if any of the following conditions: a. A class 1 command is received while in Class 2. b. A Class 2 command is received while in Class 1. c. A Class 1 or Class 2 action command is received while in data modem mode d. A Class 2 read-only parameter is given the "=" form of a +F command (e.g., AT+FAXERR=5). e. A class 2 action command is given the inappropriate "=" or "=?" (e.g., AT+FDR=?). SERIAL PORT SPEED AND FLOW CONTROL During fax mode, the DTE-DCE port speed is 19200 bps. The DCE provides a speed buffer of 1024 bytes and provides DC1/DC3 (XON/XOFF) or RTS/CTS method of controlling the data into the buffer. This flow control is controlled by AT&K3 or AT&K4 command. This method of data flow control is available only for DTE to DCE direction of data. There is no provision for data flow control from DCE to DTE. DATA STREAM TERMINATION The DCE exchanges streams of data with the DTE while executing data transfer commands. These use data stream termination described in Section 3.2/ISO 2111. The ASCII character (016) is used as a special character to shield special characters. The character pair (<106><003>) is used to mark the end of a stream. The following patterns are used: any data.... end of stream any data.... single in data any data.... delete DTE to DCE STREAMS The DCE filters the data stream from the DTE, and removes all character pairs beginning with . The DCE recognizes as the stream terminator. The DCE recognizes and reinserts a single in its place. The DTE must filter stream data to the DCE, and insert extra characters ahead of data. DCE TO DTE STREAMS The DTE must filter the data stream from the DCE, and remove all character pairs beginning with . The DTE must recognize as the stream terminator. The DTE must recognize and reinsert a single in its place. The DCE filters stream data to the DTE, and inserts extra characters ahead of data. AUTO ANSWER The DCE can answer as a data DCE or as a fax DCE. It can answer the call adaptively, i.e. it can determine whether call is 'data' or 'fax'. The +FAA parameter controls this feature. AT+FAA=1 ; Auto answer as a facsimile or a ; data modem depending on call CONNECT xxx ; DCE status response if data call +FCON ; DCE status response if fax call IDENTIFICATION OF T.30 OPTIONS Group 3 devices negotiate session parameters in DIS, DCS and DTC frames. SESSION STATUS REPORTING The DCE provides reports to the DTE on the status of a session. The DCE provides following status reports: 1. Connection and hang up status: +FCON +FHNG:<0-255> 2. Requested DIS session parameters +FDIS: reports remote facsimile capabilities. Syntax:+FDIS:VR, BR, WD, LN, DF, EC, BF, ST 3. +FDCS: reports the negotiated parameters 4. Phase C prompts: XON, XOFF, DC2 5. Phase C base status reports: depending upon copy quality and related end-of page status: +FPTS:<1-5> PROCEDURE INTERRRUPT NEGOTIATION CCITT allows a station to request a procedure interruption at the end of a page. This request is passed between stations by the PIP, PIN, and PRI-Q messages. TABLE 2-1. FAX CLASS 2 COMMANDS ----------------------------------------------------------- | Command Function | |---------------------------------------------------------| | SERVICE CLASS ID | |---------------------------------------------------------| | +FCLASS= Service Class | |---------------------------------------------------------| | CLASS 2 ACTION COMMANDS | |---------------------------------------------------------| | D Originate a call | | A Answer a call | | +FDT= Data Transmission | | +FET=N Transmit Page Punctuation | | +FDR Begin or Continue Phase C Receive Data | | +FK Session Termination | |---------------------------------------------------------| | CLASS 2 DCE RESPONSES | |---------------------------------------------------------| | +FCON Facsimile Connection Response | | +FDCS: Report Current Session | | +FDIS: Report Remote Identification | | +FCFR Indicate Confirmation to Receive | | +FTSI: Report the Transmit Station ID | | +FCSI: Report the Called Station ID | | +FPTS: Page Transfer Status | | +FET: Post Page Message Response | | +FHNG Call Termination with Status | |---------------------------------------------------------| | CLASS 2 SESSION PARAMETERS | |---------------------------------------------------------| | +FMFR? Identify Manufacturer | | +FMDL? Identify Model | | +FREV? Identify Revision | | +FDCC= DCE Capabilities Parameters | | +FDIS= Current Sessions Parameters | | +FDCS= Current Session Results | | +FLID= Local ID String | | +FCR Capability to Receive | | +FPTS= Page Transfer Status | | +FAA Adaptive Answer | | +FBUF? Buffer Size (Read Only) | | +FPHCTO Phase C Time Out | | +FAXERR Fax Error Value | | +FBOR Phase C Data Bit Order | |---------------------------------------------------------| SERVICE CLASS 2 IDENTIFICATION AND SELECTION The fax class 2 commands are summarized in Table 2-1. Three commands report identification and selection information. Each of these three commands cause the DCE to send a message to the DTE. Each message is 20 bytes (ASCII encoded) followed by the terminating character (binary 0). +FMFR?, REQUEST MANUFACTURER IDENTIFICATION The +FMFR? command caused the DCE to send a message identifying the DCE product manufacturer. The default message is: ROCKWELL OK +FMDL?, IDENTIFY PRODUCT MODEL The +FMDL? command causes the DCE to send a message identifying the DCE product model. The default message is: V.32AC OK +FREV?, IDENTIFY PRODUCT REVISION The +FREV? command causes the DCE to send a message identifying the DCE product model revision number. The typical default message is: V0.200 TR14-JXXX-001 OK SERVICE CLASS 2 ACTION COMMANDS These commands transfer data, and punctuate sessions. They also release specific T.30 messages. All action commands must be the last command on a command line. This is indicated by the terminating . All action commands initiate processes. The modem will not accept other commands from the DTE until the modem issues a final result code (e.g. OK, CONNECT). The modem will abort the process if it receives any character before the final result code is issued. ATD, ORIGINATE A CALL Syntax: ATD... The DCE can support a DTE command to originate a call using the ATD command. If this command is unsuccessful, the DCE reports an appropriate failure or error type result code such as NO CARRIER, NO DIALTONE or BUSY. If this call is successful, the typical DCE response is: ATDnn.nn (go off-hook, dial, get CED) +FCON (DCE detects flags) [+FCSI: ] +FDCS: OK The DCE dials, detects call progress and generates the CNG tone. Then it waits for a DIS frame. On detection of the first Phase B preamble (V.21 ch. 2 modulated by 300 bit/s HDLC flags) it reports the "+FCON" message to the DTE. The DCE then switches to 19.2K bps. The DCE generates a DCS frame based on the received DIS frame and on the previously set +FDIS parameter. A +FDT command from the DTE releases the DCE to transmit that DCS frame. The DCE reports the initial received T.30 negotiation messages, including the DIS frame and the optional CSI ID string. The +FDIS: report is followed by the OK final result code. ATA, ANSWER A CALL The DCE can support a DTE command to answer an incoming call using the ATA command. The DTE may issue an Answer command in response to an incoming ring. If the Answer command is unsuccessful, the DCE will report an appropriate failure or error type result code, such as NO CARRIER (see 4-7). MANUAL CALL ANSWER If this call is successful, the typical DCE response (answer and receive) is: +FCON [+FTSI: ] +FDCS: OK (DTE should issue +FDR command here) On receipt of an Answer command from the DTE, the DCE answer and generates the CED tone. The DCE then generates a DIS frame (derived from the +FDIS parameter) and hunts for the first T.30 negotiation frames. On detection of the first Phase B preamble (V.21 ch 2 modulated by 300 bit/s HDLC flags), it reports the "+FCON" message to the DTE. The DTE should report the initial received T.30 negotiation messages, including the DCS frame. The +FCS: report will be followed by the OK final result code. AUTOMATIC ANSWER The modem provides for automatic answering of incoming calls. If configured for automatic answer, the modem answers and incoming call in compliance with T.30 and reports the same messages as described for manual answer. CONNECTIONS AS A DATA MODEM If configured to do so by the +FAA parameter, the DCE will adaptively answer as a facsimile DCE or as a data DCE. If the DCE answers as a facsimile DCE or as a data DCE. If the DCE answers as a data DCE, it resets the +FCLASS parameter to 0 and issues the appropriate final result code (e.g. CONNECT or NO CARRIER) to the DTE. +FDT, DATA TRANSMISSION Syntax: +FDT The +FDT command prefixes Phase C data transmission. When the DCE is ready to accept Phase C data, it issues the negotiation responses and the CONNECT result code to the DTE. In Phase B, the +FDT command releases the DCE to proceed with negotiation, and releases the DCS message to the remote station. In Phase C, the +FDT command resumes transmission after the end of a prior transmit data stream. INITIATE PAGE TRANSMISSION Phase B DCE polled response: [+FCSI: ] ; If new CSI received [+FDIS: ] ; If new DIS received +FDCS: CONNECT ; When ready for data After placing a call, or after finishing a document exchange, the DTE may command the DCE to re-enter T.30 Phase B to attempt to negotiate a document transmission. CONTINUE A PAGE CONNECT The DTE may issue more than one +FDT command for a given page, so that different files may be concatenated together. These files must have the same format. PHASE C DATA FRAMING Phase C data must be presented to the DCE in stream mode. The DCE expects Phase C data to follow until it detects termination characters. The DCE will filter the stream as described above under the heading "Serial Port Speed and Flow Control" The DCE will acknowledge the end of the data by returning the OK result code to the DTE. If there is data underrun before the next +FDT or +FET= command, the DCE will zero-fill pad as per T.4 until the Phase C timeout (+FPHCTO) is reached, or until more data is received. The DCE appends an RTC pattern to the transmit data after an +FET= command is received from the DTE. PHASE C DATA FORMAT The Phase C data will be of the format specified by the negotiated T.30 DCS frame. The +FDCS response is defined below under the heading "+FDCS:, Report Current Session Capabilities". The subparameter values are described in table 2-2. The DCE will use the negotiated minimum Scan Time parameter from the DCS frame , and insert sufficient fill bits to pad each line to the minimum scan time. This is reported in the +FDCS:ST subparameter. If the DCE finds more than one consecutive EOL in Phase C data (e.g. RTC), it will send only one EOL. Note 1: Phase C data must conform to T.4 specifications Note 2: The DTE need not include a final RTC, since the DCE will append an RTC in response to an FET= command Note 3: Some facsimile machines may treat two EOLs as an RTC , ESCAPE FROM TRANSMISSION The DCE may request the DTE to halt Phase C transmission, by sending an cancel character (024) to the DTE. In this case, the DTE should terminate Phase C transmission, issue , and wait for the OK response code from the DCE. Table 2-2 T.30 Session Subparameter Codes |-----------------------------------------------------------------| | Label | Function | Value | Description | |--------|---------------|---------|------------------------------| | VR | Vertical | 0 | Normal, 98 lpi | | | resolution | 1 | Fine, 196 lpi | |--------|---------------|---------|------------------------------| | BR | Bit Rate | 0 | 2400 bit/s V.27 ter | | | | 1 | 4800 bit/s V.27 ter | | | (See note 1) | 2 | 7200 bit/s V.29 or v.17 | | | | 3 | 9600 bit/s V.29 or v.17 | | | | **4 | 12000 bit/s V.33 or v.17 | | | | **5 | 14400 bit/s V.33 or v.17 | |--------|---------------|---------|------------------------------| | WD | Page Width | 0 | 1728 pixels in 215 mm | | | | 1 | 2048 pixels in 255 mm | | | | 2 | 2432 pixels in 303 mm | | | | *3 | 1216 pixels in 151 mm | | | | *4 | 864 pixels in 107 mm | |--------|---------------|---------|------------------------------| | LN | Page Length | 0 | A4, 297 mm | | | | *1 | B4, 364 mm | | | | *2 | unlimited length | |--------|---------------|---------|------------------------------| | DF | Data | 0 | 1-D modified Huffman | | | Compression | 1 | 2-D modified Read | | | Format | *2 | 2-D uncompressed mode | | | | *3 | 2-D modified Read | |--------|---------------|---------|------------------------------| | EC | Error | 0 | Disable ECM | | | Correction | *1 | Enable ECM,64 bytes/frame | | | (Annex | *2 | Enable ECM,256 bytes/frame | | | A/T.30) | | | | | (See Note 2) | | | |--------|---------------|---------|------------------------------| | BF | Binary File | 0 | Disable BFT | | | Transfer | *1 | Enable BFT | | | (See Note 3) | | | |--------|---------------|---------|------------------------------| | ST | Scan Time/ | | VR=normal VR=fine | | | Line | 0 | 0 ms 0 ms | | | | 1 | 5 ms 5 ms | | | | 2 | 10 ms 5 ms | | | | 3 | 10 ms 10 ms | | | | 4 | 20 ms 10 ms | | | | 5 | 20 ms 20 ms | | | | 6 | 40 ms 20 ms | | | | 7 | 40 ms 40 ms | |--------|---------------|---------|------------------------------| Table 2-2 T.30 Session Subparameter Codes (continued) |--------|---------------|---------|------------------------------| | NOTES: 1: CCITT T.30 does not provide for the answering | | station to specify all speeds exactly using the DIS | | frame. Implementation of some BR codes (e.g.code 2) | | by an answering DCE is manufacturer specific. | | | | | | * =Not supported | | ** =RC144AC only | | | | 2: ECM has been implemented in Supra's version 1.200C. | | ECM transmit works correctly, and ECM receive works, | | but does not tell the transmitting machine that the | | fax was received correctly. | | | | 3: BFT has been implemented in Supra's version 1.200C. | | BFT transmit works correctly, and BFT receive works, | | but does not tell the transmitting machine that the | | file was received correctly. | | | |-----------------------------------------------------------------| +FET=, TRANSMIT PAGE PUNCTUATION Syntax: +FET= [, , , ] DCE response: +FPTS: ; when receive from remote OK This command is used to punctuate page and document transmission after one or more +FDT commands. This command generates T.30 Post Page Messages selected by the code (Table 2-3) The +FET= command indicates that the current page is complete; no more data will be appended to it. The value indicates if there are any additional pages are to be sent and, if so, whether there is a change in any of the document parameters. The DTE can command the DCE to generate PRI-Q messages with the +FET= command using ppm codes 4-6 (see Table 2-3) This command must be sent within the time out specified by +FPHCTO after sending Phase C data, or else the DCE will end the page and document transmission. If the Phase C timeout is reached, the DCE sends an EOP post page message and terminates the session The remote facsimile station should respond to the post page message with a post page response. The DCE will report this using the +FPTS: response (Table 2-4) END A PAGE The +FET= command causes the DCE to append an ETC (6 EOL) pattern as needed and enter Phase D by sending the selected T.30 Post Page message. The +FET=1 (EOM) command signals the remote station that the next document will have a new DCS negotiated; this causes the session to re- enter Phase B. +FDR, BEGIN OR CONTINUE PHASE C RECEIVE DATA Syntax: +FDR Default value: 3 seconds in some places The +FDR command initiates transition to Phase C data reception. This can occur after answering, dialing, a document is received, or a page is received. The DCE reports the negotiated T.30 parameters, with the remote ID information if available. When the DCE is ready to commence data transfer, it issues a CONNECT response code. If the DCE cannot resume data transfer because there is no more data, it responds OK. When the DTE is ready to accept data, it issues an character (018) to the DCE. If the DTE issues an character to the DCE for flow control, the DCE signals the DTE when its buffers are empty by sending a (<016><018>) character pair. When the DCE delivers that last byte of a page, the DCE reports the Page Transfer Status via the +FPTS: response (Table 2-4). After a Page Transfer Status Report, the DCE reports the post page message from the remote facsimile station via the +FET: response (Table 2-3) which signals the intentions of the remote station. Table 2-3. T.30 Post Page Message Codes |-----------------------------------------------------------------| | ppm | | | | Code | Mnemonic | Description | |---------|-----------------|-------------------------------------| | 1 | [PPS]-MPS | Another page next, same document | | 2 | [PPS]-EOM | Another page next | | 3 | [PPS]-EOP | no more pages or documents | | 4 | [PPS-]PRI-MPS | Another page, procedure interrupt | | 5 | [PPS-]PRI-EOM | Another doc, procedure interrupt | | 6 | [PPS-]PRI-EOP | All done, procedure interrupt | | 7 | CTC | Continue to correct | | 8-15 | EOR- | End of Retransmission (8)+ | | =8+ppm | | Post Page Message (ppm code) | |-----------------------------------------------------------------| Table 2-4. T.30 Post Page Response Message Codes |-----------------------------------------------------------------| | ppr | | | | Code | Mnemonic | Description | |---------|-----------------|-------------------------------------| | 0 | PPR | Partial page errors | | 1 | MCF | Page Good | | 2 | RTN | Page bad, retrain requested | | 3 | RTP | Page good, retrain requested | | 4 | PIN | Page bad, interrupt requested | | 5 | PIP | Page good, interrupt requested | |-----------------------------------------------------------------| The DCE holds the post page response message to the remote facsimile station (MCF, etc.), represented in the +FPTS parameter until the next +FDR command. The DTE may modify the +FPTS parameter before issuing the +FDR command which releases that message. The DTE must issue a +FDR command to release Post Page Messages. INITIATE DOCUMENT RECEPTION The +FDR command may be issued in Phase B after an answer command, or in Phase B after a pervious document. The DCE response in stream mode is: +FCR ; when CFR sent [+FTSI: ] ; if new TSI received +FDCS: ] ; if new DCS CONNECT ( needed from DTE here) +FPTS: , [, , ] +FET: OK (DTE must issue +FDR command to release post page response) CONTINUE DOCUMENT RECEPTION The DTE may issue a +FDR command in Phase D, which releases the post page message, and indicates readiness to receive another page after receipt of a Multipage (+FET:0) or PPS-NULL (+FET:3) message. The DCE response will be: CONNECT ( needed from DTE here) +FPTS: , [, , ] +FET: OK (DTE must issue +FDR command to release post page response. If done receiving: +FHNG: OK Continue page reception PHASE C DATA FRAMING Phase C data may be presented to the DTE in stream mode. The DCE will transfer a stream of data to the DTE, followed by the stream termination characters. The DCE will filter the stream as described above under the heading "Serial Port Speed and Flow Control". PHASE C DATA FORMAT The received data format is negotiated under T.30 reported by the +FDCS:VR,BR,WD,LN,DF,EC,BF,ST response. The DCE will delete the terminating RTC (6 EOLs) patterns. The DCE may strip zero fill bits from the data, to minimize storage needs. , ESCAPE FROM RECEPTION From the +FDR command until the end of Phase D Date, the DCE is in a data transfer state, and will not respond to DTE command characters. The DCE will respond to three ASCII control characters, (019) flow control characters, and cancel (024). Upon receipt of the character, the DCE will terminate the reporting of received data by sending trailing characters to the DTE, and will then execute an implied +FK command in order to conduct an orderly disconnection. +FK, SESSION TERMINATION Syntax: +FK The +FK command causes the DCE to terminate the session in an orderly manner. In particular, the DCE will send a DCN message at the next opportunity and hang up. At the end of the termination process, the DCE will report the +FHNG response with result code (Table 2-5). This operation can be invoked by using the cancel character during Phase C data reception (see prior section). The DCE will wait until the current page completes, unless the reception is of unlimited length; in that case, the DCE may halt reception and terminate the session at any time. SERVICE CLASS 2 DCE RESPONSES The DCE sends information responses to the DTE as a facsimile session proceeds. They indicate the state of the facsimile session and convey need information. These messages are solicited messages generated in execution of DTE action commands described above under the major heading "Service Class 2 Action Commands". The DCE precedes and follows the following information responses with . The DCE provides the on-line status of several session parameters when they are available during T.30 handshaking. These include the remote ID string and the DIS/DCS parameters. These responses report the T.30 session parameter frames. The subparameters are described in Table 2-2. +FCON, FACSIMILE CONNECTION RESPONSE +FCON indicates connection with a fax machine. It is released by detection of HDLC flags in the first received frame +FCON is generated in response to an Originate or Answer command. +FDCS:, REPORT CURRENT SESSION CAPABILITIES Syntax: +FDCS:VR,BR,WD,LN,DF,EC,BF,ST +FDCS: reports the negotiated parameters. Phase C data will be formatted as described by the subparameters. This message may be generated in execution of +FDT or +FDR commands before the CONNECT result code if new DCS frames are generated of received. (See Table 2-2.) +FDIS:, REPORT REMOTE STATION CAPABILITIES Syntax: +FDIS:VR,BR,WD,LN,DF,EC,BF,ST +FDIS: reports remote facsimile station capabilities and intentions. The parameters are provided in ASCII notation. (See Table 2-2.) This message is generated in execution of Originate, Answer, +FDT, or +FDR commands. +FCFR, INDICATE CONFIRMATION TO RECEIVE Syntax: +FCFR The DCE sends a +FCFR response to the DTE upon reception of an acceptable TCF training burst and a valid DCS signal from the remote machine. This indicates that the DCE will receive Phase C data after the remote station receives the local DCE's CFR message. The +FCFR message is generated in execution of a +FDR command. +FTSI:, REPORT THE TRANSMIT STATION ID Syntax: +FTSI:" " Transmit Station ID This response reports the received transmit station ID string, if any. This message is generated in execution of Originate, Answer, +FDT, or +FDR commands. +FCSI:, REPORT THE CALLED STATION ID Syntax: +FCSI:" " Called Station ID This response reports the received called station ID string, if any. This message is generated in execution of Originate, Answer, +FDT, or +FDA commands. +FPTS:, RECEIVE PAGE TRANSFER STATUS Syntax: +FPTS: , [, , ] The +FPTS: is generated by the DCE at the end of Phase C data reception in execution of a +FDR command. The is generated by the DCE; it depends on the DCE capabilities at T.4 error checking. See Table 2-4 for values. The receiving DCE will count the lines and may optionally generate bad line counts. These values are: = line count = bad line count = and write a modified value into the +FPTS parameter. The DCE will hold the corresponding Post Page Response message until released by a +FDR command from the DTE. +FET:, POST PAGE MESSAGE RESPONSE Syntax: +FET: The +FET: response is generated by a receiving DCE after DCE after the end of Phase C reception on receipt of the post-page message from the transmitting station. The +GET: response is generated in execution of a +FDR command. The codes respond to the T.30 pst page messages (Table 2-3) +FPTS:, TRANSMIT PAGE TRANSFER STATUS Syntax: +FPTS: The +FPTS: response reports a number representing the copy quality and related post page message responses received from the remote DCE. The set of valid values are defined in Table 2-4. The +FPTS: response is generated in execution of a +FET= command. +FHNG:, CALL TERMINATION WITH STATUS Syntax: +FHNG: +FHNG indicates that the call has been terminated. The hangup cause is reported and stored in the +FAXERR parameter for later inspection. The values are described in Table 2-5. +FHNG: is a possible intermediate result code to any DTE action command described above under the major heading "Service Class 2 Action Commands". It is always followed by the OK final result code. Upon termination of a call, the DCE determines the cause of termination and reports it as part of the FHNG: response. It also stores this code in the +FAXERR parameter for later inspection. The hangup values are organized according to the phases of the facsimile transaction as defined by T.30. A COMREC error or RSPREC error indicates that one of two events occurred. 1) a DCN (disconnect) signal was received, or 2) an FCS error was detected and the incoming signal was still present after 3 seconds. The table values are in decimal notation. Leading zero characters are optional. Table 2-5 Hangup Status Codes |------------------------------------------------------------| | Code | Cause Description | |----------|-------------------------------------------------| | 0-9 | CALL PLACEMENT AND TERMINATION | |----------|-------------------------------------------------| | 0 | Normal and proper end of connection | | 1 | Ring Detect without successful handshake | | 2 | Call aborted, from +FK or AN | | 3 | No Loop Current | |----------|-------------------------------------------------| | 10-19 | TRANSMIT PHASE A & MISCELLANEOUS ERRORS | |----------|-------------------------------------------------| | 10 | Unspecified Phase A error | | 11 | No Answer (T.30 T1 timeout) | |----------|-------------------------------------------------| | 20-39 | TRANSMIT PHASE B HANGUP CODES | |----------|-------------------------------------------------| | 20 | Unspecified Transmit Phase B error | | 21 | Remote cannot receive or send | | 22 | COMREC error in transmit Phase B | | 23 | COMREC invalid command received | | 24 | RSPEC error | | 25 | DCS sent three times without response | | 26 | DIS/DTC received 3 times; DCS not recognized | | 27 | Failure to train at 2400 bps or +FMINSP value | | 28 | RSPREC invalid response received | |----------|-------------------------------------------------| Table 2-5 Hangup Status Codes (continued) |----------|-------------------------------------------------| | 40-49 | TRANSMIT PHASE C HANGUP CODES | |----------|-------------------------------------------------| | 40 | Unspecified Transmit Phase C error | | 43 | DTE to DCE data underflow | |----------|-------------------------------------------------| | 50-69 | TRANSMIT PHASE D HANGUP CODES | |----------|-------------------------------------------------| | 50 | Unspecified Transmit Phase D error | | 51 | RSPREC error | | 52 | No response to MPS repeated 3 times | | 53 | Invalid response to MPS | | 54 | No response to EOP repeated 3 times | | 55 | Invalid response to EOM | | 56 | No response to EOM repeated 3 times | | 57 | Invalid response to EOM | | 58 | Unable to continue after PIN or PIP | |----------|-------------------------------------------------| | 70-89 | RECEIVE PHASE B HANGUP CODES | |----------|-------------------------------------------------| | 70 | Unspecified Receive Phase B error | | 71 | RSPREC error | | 72 | COMREC error | | 73 | T.30 T2 timeout, expected page not received | | 74 | T.30 T1 timeout after EOM received | |----------|-------------------------------------------------| | 90-99 | RECEIVE PHASE C HANGUP CODES | |----------|-------------------------------------------------| | 90 | Unspecified Receive Phase C error | | 91 | Missing EOL after 5 seconds | | 92 | Unused code | | 93 | DCE to DTE buffer overflow | | 94 | Bad CRC or frame (ECM or BFT modes) | |----------|-------------------------------------------------| | 100-119 | RECEIVE PHASE D HANGUP CODES | |----------|-------------------------------------------------| | 100 | Unspecified Receive Phase D errors | | 101 | RSPREC invalid response received | | 102 | COMREC invalid response received | | 103 | Unable to continue after PIN or PIP | |----------|-------------------------------------------------| | 120-255 | RESERVED CODES | |------------------------------------------------------------| SERVICE CLASS 2 PARAMETERS All Service Class 2 parameters can be read, written, and tested for range of legal values by the DCE. The general syntax is described above under the major heading "Command Syntax And Guidelines". Group 3 FAX devices negotiate session parameters in DIS, DCS, and DTC frames. The following parameters are provided to condition the facsimile DCE for the capabilities it will offer and to report the session settings negotiated. The three primary T.30 session parameters are +FDCC, +FDIS and +FDCS. They are compound parameters, using values listed in Table 2-2. +FDCC, DCE CAPABILITIES PARAMETERSv Write Syntax: +FDCC:VR,BR,WD,LN,DF,EC,BF,ST Valid values See Table 2-2 Default values 0,3,0,2,0,0,0,0 (RC96AC) 0,5,0,2,0,0,0,0 (RC144AC) +FDCC allows the DTE to sense and constrain the capabilities of the facsimile DCE from the choices defined in CCITT t.30 Table 2. When +FDCC is modified by the DTE, the DCE copies +FDCC into +FDIS. +FDIS, CURRENT SESSIONS CAPABILIIES PARAMETERS Write Syntax: +FDIS:VR,BR,WD,LN,DF,EC,BF,ST Valid values See Table 2-2 Default values 0,3,0,2,0,0,0,0 (RC96AC) 0,5,0,2,0,0,0,0 (RC144AC) The +FDIS parameter allows the DTE to sense and constrain the capabilities used for the current session. The DCE uses +FDIS to generate DIS or DTC messages directly, and uses +FDIS and received DIS messages to generate DCS messages. The DCE initializes the +FDIS parameter from the +FDCC parameter on initialization, when +FDCC is written, and at the end of a session. +FLID=, LOCAL ID STRING Write Syntax +FLID=" " Valid values: 20 character ASCII string Default value: Empty If FLID is not a null string, it generates a TSI or CSI frame. Table 3/T.30 includes digits 0-9, "+" and space. If the DCE supports use of Table 3/t.30 only, the response to a +FLID=? command is "<20)(32, 43, 48-57)". If the DCE supports printable ASCII <, the response is "(20)(32-127) " The first "(20)" represents string length: the second (character values) field reports supported string values. Notes: 1. The string is saved in RAM. 2. Non-numeric characters are not filtered out. +FCR, CAPABILITY TO RECEIVE Write Syntax: +FCR= Valid values: 1,0 Default values 0 +FCR=0 indicates that the DCE will not receive message data. This can be sued when the DTE has insufficient storage. The DCE can send and can be polled for a file. +FCR is sampled in CCITT T.30 Phase A and Phase D +FPTS=, PAGE TRANSFER STATUS Write syntax: +FPTS= Valid Values: 1,2,3,4,5 Default value: 0 +FCQ, COPY QUALITY CHECKING Write Syntax: +FCQ= Valid Values: 0 Default Value: 0 This parameter controls Copy Quality checking by a receiving facsimile DCE. The DCE returns +FCQ=0 which indicates the DCE does no quality checking. The DCE will generate Copy Quality OK (MCF) responses to complete pages, and set +FPTS=1. +FPHCTO, DTE PHASE C RESPONSE TIME-OUT Write Syntax: +FPHCTO= Valid Values: 0-255, 100 millisecond units Default Value: 30 The +FPHCTO command determines how long the DCE will wait for a command after reaching the end of data when transmitting in Phase C. When this time-out is reached, the DCE assumes there are no more pages and no documents to send. It then sends the T.30 EOP response to the remote device. +FAXERR, T.30 SESSION ERROR REPORT Read Syntax: +FAXERR= , read only Valid values: 0-255, see table 2-5 for meaning This read-only parameter indicates the cause of the hangup. Table 2-5 shows the valid values for this parameter as well as the meaning of the each value. +FAXERR is set by the DCE at the conclusion of a fax session. The DCE resets +FAXERR to 0 at the beginning of Phase A off- hook time. +FBOR, DATA BIT ORDER Write Syntax: +FBOR=
Valid Values: 0,1 Default value: 0 This parameter controls the mapping between PSTN facsimile data and the DTE-DCE link. There are two choices: DIRECT: The first bit transferred to each byte on the DTE-DCE link is the first bit transferred on the PSTN data carrier. REVERSED: The last bit transferred of each byte on the DTE-DCE link is the first bit transferred on the PSTN data carrier. There are two data types to control: This command controls Phase C data (T.4 encoded data) transferred during execution of +FDT or +FDR commands. The following two codes are supported. +FBOR=0 selects direct bit order for Phase C data +FBOR=1 selects reversed bit order for Phase C data Note that this parameter does not affect the bit order of control characters generated by the DCE. +FAA, ANSWER PARAMETER Write syntax: +FAA= Valid values: 0,1 Default value 0 +FAA=0 constrains the DCE to answer as set by +FCLASS +FAA=1 indicates that the DCE can answer and automatically determine whether to answer as a Class 2 facsimile DCE or as a data modem. If the DCE automatically switches, it modifies FCLASS appropriately. Class 2 adaptive answer is implemented as follows: First, a data mode handshake is attempted. If the DCE has been configured for automode detection (using the A command), the DCE may try several protocols be terminating attempts to make a data mode connection. This can take as long as 6-8 seconds. If the data mode connection attempt fails, a facsimile Class 2 connection is assumed. When a connection is made, a result of the adaptive answer, the DCE issues the D or FAX result code before the CONNECT or +FCC message to inform the DTE of the connection type. A making a class 2 connection, the DCE stays on-line rather than going into the command mode as with a Class 2 connection.
Of Special Interest to Supra Users: +FAA=n (CLASS 2 Only) Adaptive Answer/Silent Answer Mode Control n=0 Disable Both n=1 Adaptive Answer ONLY n=2 Adaptive Answer & Silent Answer n=3 Silent Answer ONLY
+FBUF?, BUFFER SIZE Read syntax: +FBUF? DCE response syntax, , , where: = total buffer size = XOFF threshold = XON threshold = current buffer byte count The +FBUF parameter allows the DTE to determine the characteristics of the DCE's data buffer. Data buffers are used for flow control. Use of the reported values allow the DTE to transfer data without provoking XOFF. EXAMPLE SESSIONS Table 2-6 and 2-7 show the typical command and responses for sending and receiving two pages respectively. Table 2-6 Send two pages, 1-D data, no errors |----------------------------------------------------------------------| | DTE COMMAND | DCE RESPONSE | LOCAL DTE ACTION |REMOTE STATION ACTION | |-------------|--------------|------------------|----------------------| | AT+FCLASS=2 | OK | Set Class 2 | | |-------------|--------------|------------------|----------------------| | AT+FLID= | | | | | | OK | Set local ID | | |-------------|--------------|------------------|----------------------| | AT | | off hook, dial | answer | | | | send CNG | send [CED], | | | +FCON | detect flags | v.21 flags | | | +FDIS: | get CSI | CSI | | | +FDIS: | get DIS | DIS | | | OK | | | |-------------|--------------|------------------|----------------------| | AT+FDT | | send TSI | get TSI | | | | send DCS | get DCS | | | | send TCF | get TCF | | | +FDCS: | get CFR | send CFR | | | CONNECT | send carrier | receive carrier | | | | | | | <1st page> | | send page data | receive page data | |