FAX/DATA MODEM USER’S MANUAL
Notice: Hayes is a trademark of Microcomputer Products Inc.
Table of Contents FCC/DOC REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . i FCC General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . i FCC Notice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i DOC Notice . . . . . . . . . . . . . . . . . . . . . . . . ..III INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TESTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 Local Analog Loopback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 Local Analog Loopback with Self-Test . . .. . . . . . . . . . . . . 56 Remote Digital Loopback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 Remote Digital Loopback with Self-Test . . .. . . . . . . . . . . 59 Local Digital Loopback . . . . .. . . . . . . . . .
i - FCC/DOC REQUIREMENTS i.1 FCC General Information The Federal Communications Commission (FCC) of the United States restricts specific uses of modems, and places registration responsibilities on both the manufacturer and the individual user: 1. The modem may not be connected to a party line or to a coin operated telephone, 2. The modem manufacturer must make any repairs to the modem to maintain valid FCC registration. 3.
stalled and used the instructions. may cause interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation, If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try and correct the interference by one or more of the following measures: Reorient or relocate the receiving antenna.
i.3 DOC Notice Notice: The Canadian Department of Communications label identifies certified equipment. This certification means that the equipment meets certain telecommunications network protective, operational and safety requirements. The Department does not guarantee the equipment will operate to the user’s satisfaction. Before installing this equipment, users should ensure that it is permissible to be connected to the facilities of the local telecommunications company.
Caution: Users should not attempt to make such connections themselves, but should contact the appropriate electric inspection authority. or electrician, as appropriate. The Load Number (LN) assigned to each terminal device denotes the percentage or the total load to be connected to a telephone loop which is used by the device, to prevent overloading.
1- INTRODUCTION Congratulations on your purchase of this outstanding Fax/Data Modem. This manual describes how to operate your new Fax/Data Modem. Instructions for installing your Fax/Data Modem will be found in the Installation Manual, while the information in this manual, deals exclusively with the operation of the modem after it is installed, such as the command set, the internal configuration registers, troubleshooting and testing.
If you are already familiar with the use of a modem and the Hayes AT command set, this modem will be extremely easy for you to use. Just read the installation procedures in the installation manual and you are ready to begin operation. If you are new to modem communications, we recommend that you read through this manual first. If you come across terms that you don’t understand. consult the glossary. Words in boldface type are command names, commands. or default settings.
2- COMMAND REFERENCE This chapter provides an alphabetized reference with examples for all commands for the modem. The system of commands is depicted below in Figure 2-1. To use these commands for dialing or configuring the modem, make sure the communications software package you will be using lets you operate the modem through its internal commands. If your software permits use of the modem’s internal commands, read this chapter. If not, read your software user’s manual and ignore the rest of this manual.
2.1 General Command Information Except for the A/ command and the TIES escape sequence described in Section 2.4, all commands must be prefixed with the attention code AT. For instance, the A command (below) would be entered as: “AT A ”. Without the AT prefix, the command line cannot be executed. Once entered, AT cannot be deleted with the Backspace or Delete keys. More than one command can be placed on a single line and, if desired, separated with spaces for readability.
buffer. The A/ command is the only command not preceded by ‘AT’ and ended by a carriage return. Go On-line in Answer Mode A This command instincts the modem to go off-hook immediately and then make a handshake with the remote modem. Handshaking is not available during leased line operation. This command is useful for manually answering a call or establishing a back-to-back connection with an originate mode modem.
Go On-line in Originate Mode D D instructs the modem to go off-hook immediately and automatically dial the number contained in the dial string following D. The dial string may contain any of the dial modifiers contained in the following section. The D command without a dial string is usually used to switch from voice conversation to data communication or to call a remote modem in leased-line operation mode. During this kind of operation.
In Identification/Checksum Option This command causes the modem to send product code and hardware setup information to the DTE. I0 I1 I2 I3 I4 Report product code. (default) Firmware version #. Verify ROM checksum. Device set name. Modem configuration. 0= Hayes Escape Sequence. Bit 0 1 =TIES Escape Sequence, Bit 1 0= Data/fax/voice without V.42/MNP firmware. 1 =Data/fax/voice with V.42/MN P firmware. 0= Serial host interface, Bit 2 1 =Parallel host interface. 0=No external Static RAM present.
Control Speaker Volume Ln L0 L1 L2 L3 Low volume. Low volume. Medium volume. (default) High speaker volume. Monitor Speaker On/Off Mn M0 M1 M2 M3 Nn Speaker is always off. Speaker is off while receiving carrier. (default) Speaker is always on. Speaker disabled while dialing or receiving carrier Select Data Rate Handshake This command specifies whether the resulting modem-to-modem data rate can be different than the local DTE-to-modem data rate.
On Return to the On-line State 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 ON-to-OFF transition of DTR with the AT&D1 option in effect, the user may return to the data mode without terminating a call by issuing the ATO command. O0 O1 P Causes the modem to return to the data mode. (default) Enters on-line data mode with a retrain before returning to on-line data mode.
Reading and Writing to S Registers Sn Sn? Sn=x Reads S Registers: Reads the contents of the S register specified by ‘n’. Writing to Registers: Writes the value of x to the specified S register. All the registers will return the OK response if x is a legal value. (n= 0-30, x=0-255) Set Tone Dial as Default T Causes the modem to assume that all subsequent dial commands are tone dial. Select Word or Digit Result Codes Vn Displays. result codes in digital format.
The partial connect message reports CONNECT, the full message reports CONNECT XXXX, where XXXX is the data rate. Yn Enables or Disables Long Space Disconnect Disables Long Space Disconnect. (default) Enables Long Space Disconnect. Y0 Y1 Zn Reset Zn, which must be placed at the end of the command line, resets the active configuration of the modem to the stored configuration saved in nonvolatile RAM, hanngs up the modem. and clears the command buffer.
&Dn DTR Option This command controls how the modem responds to DTR, After toggling DTR, the host should wait 200 ms before modifying the UART registers or sending a new command to the modem as the modem does not send an ‘OK’ message to indicate it has performed the requested function. &D0 &D1 &D2 &D3 Note : &F In asynchronous mode (&Q0), the modem ignores DTR. The modem switches from data mode to command mode when an on-to-off transition of DTR occurs.
Set Guard Tone &Gn &G0 &G1 &G2 Guard tone disabled. (default) 550 Hz guard tone enabled. 1800 Hz guard tone enabled. Auxiliary Relay Control &Jn This command is only included for compatibility and performs no function except to load the S-register. &J0 &J1 &J0 command. (default) &J1 command. &Pn Select Pulse Dialing Make/Break Ratio &P0 &P1 Sets a 39/61 make/break ratio at 10 pps. (default) Sets a 33/67 make/break ratio at 10 pps.
&Tn Testing and Diagnostics (See Chapter 4) This command is used 10 initiate and terminate loopback tests for testing modem-tomodem and DTE-to-modem data communication integrity. &T0 &T1 &T3 &T4 &T5 &T6 &T7 &T8 Terminates test in progress. (default) Local analog Ioopback. Local digital Ioopback. Grants RDL request from remote modem. Denies RDL request from remote modem. Remote digital Ioopback. Remote digital Ioopback with self-test. Local analog Ioopback with self-test.
&V0 &V1 Stored profile 0. (default) Stored profile 1.
&Wn Store the Current Configuration to Nonvolatile RAM &W0 &W1 &Yn Select the Default Profile &Y0 &Y1 &Zn Writes the current active configuration to profile 0 in nonvolatile RAM. (default) Writes the current active configuration to profile 1 in nonvolatile RAM. Uses profile 0 on power-up. (default) Uses profile 1 on power-up. Store Telephone Numbers (n=0 to3) &Zn Stores one of four dial strings (including a telephone number) of up to 38 digits in nonvolatile RAM.
2.2b Commands Preceded by\ \An Maximum MNP Block Size Sets maximum block size for MNP connections. Use this command to transmit smaller blocks of data in a reliable link connection, \A0 \A1 \A2 \A3 \Bn Sets maximum block size to 64 characters. Sets maximum block size to 128 characters. Sets maximum block size to 192 characters.
\C0 \C1 \C2 \Gn Modem to Modem Flow Control (XON/XOFF) \G0 \G1 Disable flow control. (default) Enable flow control. Enable/Disable DTE Auto Rate Adjustment \Jn \J0 \J1 \Kn Does not buffer data. (default) Buffers data for four seconds until 200 characters have been buffered or SYN character is detected, then switches to reliable mode. If the buffer fills, data is passed to the serial port. DoeS not buffer data.
n=1 n=3 n=5 Destructive/expedited, Non-destructive/expedited. Non-destructivelnonexpedited. In Command State, if reliable mode then transmit break to remote: n = 0,1 Destructive/expedited. n = 2,3 n = 4,5 Non-destructive/expedited. Non-destructive/non-expedited. In Connect State, if direct mode then receive break at serial port: n = 0,2,4 n = 1,3,5 Immediately send break and enter command state. Immediately send break through.
\N3 \N4 V.42 Auto-reliable Mode * - If V.42 detection is enabled (-Jn), a LAPM or MNP link can be detected and negotiated, otherwise only LAPM will be attempted. If configured for -J0 and a protocol connection is not made, the modem will hang up. If configured for -J1 and a protocol connection is not made, the modem will fall back to speed buffering mode. (default) V.42 Reliable - The modem attempts to negotiate LAPM error correction, hanging up if it fails.
\Q0 \Q1 \Q2 \Q3 \Tn Disables flow control. XON/XOFF software flow control. Unidirectional hardware flow control. Bidirectional hardware flow controll. (default) Set Inactivity Timer During a normal or reliable connection, if no data is sent or received within the inactivity time period, the link will be disconnected. The default of zero disables this feature. n=0-90 \T0 \U Lenth in minutes. Disables inactivity timer.
\V1 \V2 \Xn Enables modified MN P codes. Enables extended V.42 codes. Set XON/XOFF Passthrough If software flow control is enabled (\Ql), this command defines whether the XON (11 hex) and XOFF (13 hex) characters received from the DTE are sent to the remote modem. In addition, if the modem port flow control is enabled (\G1) in normal mode, the command specifies whether the XON and XOFF characters received from remote modem are sent to the DTE. In both cases, flow control operation is not affected.
\Z Switch to Normal Mode During an MNP link, the modem will disconnect the link (exit error correction/ data compression) and change to narmal mode, without disconnecting the modemto-modem connection. 2.2.c Commands Preceded by % %An Set Auto-reliable Fallback Character In auto-reliable mode (\N3), with auto-reliable fallback character enabled (\C2), receipt of the fallback character from the line during the V.42 detection phase will cause to modem to switch to normal mode.
%En Auto-retrain Control (V.22 bis and V.32 bis only) This command controls whether the modem will automatically initiate a modem retrain whenever the Received Data signal quality falls below a threshold that may affect data reliability. The value for ‘n’ is stored in the NVRAM, but it is not displayed by the ‘AT&Vn’ command. %E0 %E1 %Gn Disabled. Enabled. (default) Auto Fallforward/fallback Enable (V.
8-255 Modem performs a Retrain. (i.e., if configured for %E1) 2.2.d Commands Preceded by - and “ -Cn Generate Data Modem Calling Tone This command allows the DTE to select whether the modem will send 1300 Hz calling tone when originating a Data Modem connection. -C0 -C1 -Jn Calling tone disabled. (default) Calling tone enabled. Set V.42 Detect Phase In V.42 modes (\N3, \N4), this command specifies whether the modem will detect V.
“H0 “H1 “H2 “H3 “On Disables V.42 bis. Enables V.42 bis only when transmitting data. Enables V.42 bis only when receiving data. Enables V.42 bis for both transmitting and receiving data. (default) V.42 bis String Length This command specifies the maximum number of characters that can be compressed into one V.42 bis code word. The default value of 16 optimizes throughput for most file types. n=6-250=Number of characters 2.
, Pause “,”, placed anywhere in the dial string, tells the modem to pause for the number of seconds specified by S-register S8 before processing the rest of the dial string. ! Initiate a Hookflash “!”, placed anywhere in the dial string, tells the modem to initiate a hookflash, which means to hang up for 0.75 seconds and then go off-hook again before processing the rest of the dial string. This modifier allows access to PBX features like call transferring.
P Pulse Dialing P, placed ahead of a number, tells the modem to dial a number using pulse dialing. R Reverse Originate Mode to Answer Mode R, which can only be placed at the end of the dial string, tells the modem to change from the originating mode to the answer mode once it dials all the digits before the R. This modifier is used to call an originate-only modem, S Dial a Stored Number S is used to dial one of four numbers stored in nonvolatile memory.
W Wait for Dialtone Causes the modem to look for dial tone for a specified amount of time. If dial tone or the amount of time specified by the S-register S6 times-out, the modem will then process the next command in the dial string. If a busy signal is detected, the modem will respond back to the DTE with a busy response code, and then go into offline command mode. 2.
and then waits indefinitely for an incoming valid ‘AT’ command string from the DTE. If the next character received by the modem is not an ‘A’ or ‘a’, then the modem returns to data mode and sends a ‘CONNECT message back to the DTE. If the modem receives an ‘A’ or ‘a’, the modem disables the EPD timer (if it has not time out) and sends the character to the remote modem. The modem then stores any received data from the DTE into the modem internal command buffer and sends the data to the remote modem.
provided below. Format: char1=char2=char3=escape character (S2) e.g., DTE: +++AT DCE: OK NOTE: TIES requires that the three-character escape sequence be contiguous and not repeated. The character immediately preceding the first character of the three-character sequence cannot be the same as the escape character. Therefore, ‘+++AT’ is valid, but ‘++++ AT’ is not. 2.
Numeric Code 8 Verbose Code 10 NO ANSWER CONNECT 2400 11 12 14 16 17 CONNECT 4800 CONNECT 7200 CONNECT 9600 CONNECT 12000 CONNECT 14432 Modified Response Codes (\V1) Numeric Code Verbose Code 22 24 25 26 CONNECT CONNECT CONNECT CONNECT 27 CONNECT 7200/REL 28 29 30 CONNECT 9600/REL CONNECT 12000/REL CONNECT 14400/REL 300/REL 1200/REL 2400/REL 4800/REL V.
Numeric Code Verbose Code 36 37 38 39 40 42 44 45 46 47 48 49 50 54 55 56 57 58 59 60 CONNECT 4800/REL-MNP CONNECT 7200/REL-MNP CONNECT 9600/REL-MNP CONNECT 12000/REL-MNP CONNECT 14400/REL-MNP CONNECT 300/REL-MNP 5 CONNECT 1200/REL-MNP 5 CONNECT 2400/REL-MNP 5 CONNECT 4800/REL-MNP 5 CONNECT 7200/REL-MNP 5 CONNECT 9600/REL-MNP 5 CONNECT 12000/REL-MNP 5 CONNECT 14400/REL-MNP 5 CONNECT 1200/REL-LAPM CONNECT 2400/REL-LAPM CONNECT 4800/REL-LAPM CONNECT 7200/REL-LAPM CONNECT 9600/REL-LAPM CONNECT 12000/REL-LAP
3 - S REGISTER REFERENCE Your modem has status registers. These registers are memory locations inside your modem which control your modem’s operation. You usually do not have to worry about setting any register because the default values work for most applications. The S registers are summarized in Fig. 3-1, along with their default values.
3.1 Register Summary The following chart summarizes your modem’s registers: Command S0 * S1 S2 * S3 S4 S5 S6 * S7 * S8 * S9 * S10 * S11 * S12 * S13 S14 * S15 S16 * S17 S18 * S19 S20 36 S-Registers Default Type Function R/W No.
S21 S22 S23 S24 S25 S26 S27 S30 S37 S90 S108 S109 NOTE: * * * none none none none * * * * * * * * (*) (-) 5 1 none 10 0 0 1 62 R Bit-mapped options R Bit-mapped options R Bit-mapped options Reserved R/W Detect DTR change R/W RTS-to-CTS deIay interval R Bit-mapped options R/W Sleep mode timer R/W Maximum line speed attempted R/W Disconnect Inactivity timer R/W Retrain signal quality selector R/W Line speeds permitted Value Saved in NVRAM (R) Read-only register (R/W) Read/write register Reserved registe
3.2 Glossary of the S Registers S0 Number of Rings to Auto-Answer On Assigning S0 a value from 1 to 255 configures the modem for auto-answer mode, The modem will automatically go off-hook and initiate a data-mode-answer mode handshake after detecting the specified number of rings, Range: n=0 n = 1-255 S1 0-255 rings Auto-answer mode disabled. Auto-answer mode enabled. Ring Count of ring signals detected by the modem.
defaut is ‘+’ or ASCII decimal 43. The escape character may range between 0-127. Any value over 127 will disable the escape sequence. Range: 0-127 Default: 43 (’+’) S3 Carriage Return Character S3 specifies the ‘AT’ command string terminator and modem response code terminator. The factory default is a or carriage return (ASCII decimal 13). Range: 0-127 Default: 13 (carriage return) S4 Line Feed Character S4 specifies the line feed character.
S5 Backspace Character S5 specifies the backspace character that is used to delete the last-entered character. After receiving a backspace character, the modem sends three characters to the DTE: a backspace character, a space character, and then another backspace character. Range: 0-32, 127 Default: 8 (BS) S6 Wait Before Blind Dialing S6 specifies the amount of time after the modem goes off-hook before the modem starts dialing the first telephone number.
remote modem carrier after dialing the telephone number. If the remote modem carrier is not detected within the S7 time limit, the modem will hang-up and send a NO CARRIER response code to the DTE. If the remote modem carrier is detected, the modem goes into on-line data mode and sends a CONNECT message to the DTE. S7 also specifies the time duration for the ‘W' (wait for dial tone) dial modifier.
carrier detection will occur due to noise on the telephone line. Range: 1-255 (1/10 of a second) Default: 6 (equals 0.6 seconds) S10 Lost Carrier Hang Up Delay S10 specifies amount of time the modem waits before hanging up after the loss of the remote modem carrier. This delay allows for the temporary loss of the remote modem carrier without causing the local modem to hang up. When set to 255, the modem will not disconnect upon loss of the remote modem carrier.
S12 Guard Time S12 is used to specify guard and detect times used for the TIES Escape Sequences. For the TIES Escape Sequence, S12 specifies the maximum time limit after receiving the three escape characters and no other characters before sending an OK message to the DTE. Range: 0-255 (1/50 of a second) Default: 50 (equals 1 second) S13 Reserved S14 Bit Mapped Options Bit Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Value Description 0 1 0 1 0 1 0 1 Reserved E0 is selected. El is selected.
Bit Value Bit 7 0 1 Description Answer. Originate. (default) S15 Reserved S16 Modem Test Options Bit Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Value Description 0 1 0 0 1 0 1 0 1 0 1 Bit 6 Bit 7 44 0 1 0 Local analog Ioopback disabled. (default) Local analog Ioopback enabled. (&T1) Reserved. Local digital Ioopback disabled. (default) Local digital Ioopback enabled. (&T3) Remote digital Ioopback off. (default) Remote digital Ioopback in progress. (&T6) RDL not active.
S17 Reserved S18 Modem Test Timer S18 specifies the amount of time that the modem will conduct one of the Ioopback tests (&Tn). After timing out, the modem returns back to command mode. Setting S18 to zero disables the modem test timer; the Ioopback test must be terminated by issuing the appropriate escape sequence followed by an ‘AT&T0’ or ‘ATH’.
Bit Value Bits 4-3 00 01 10 11 0 1 0 1 0 1 Bit 5 Bit 6 Bit 7 S22 Bit Mapped Options Bit Value Bits 1-0 Bits 3-2 Bits 6-4 46 &D0 is selected, &D1 is selected. &D2 is selected. (default) &D3 is selected. &C0 is selected. &C1 is selected. (default) &S0 is selected. (default) &S1 is selected. Y0 is selected. (default) Y1 is selected, 00 01 10 11 00 01 10 11 000 001 010 011 100 101 110 111 Description Reserved. L1 is selected, L2 is selected. (default) L3 is selected. M0 is selected.
Bit Value Description Bit 7 0 1 S23 Bit Mapped Options Bit Bit 0 Value 0 1 000 Bit 3,2,1 001 010 011 100 101 110 111 Bit 5,4 00 01 10 11 Bit 7,6 00 01 10 11 S24 &P0 is selected. (default) &P1 is selected. Description &T5 is selected. &T4 is selected. (default) 0-300 bps communications rate. 1200 bps. 2400 bps. 4800 bps. 7200 bps. 9600 bps. 19.2 Kbps. 38.4 kbps. Even parity. (default) Space parity/no parity. Odd parity, Mark. &G0 is selected. (default) &G1 is selected. &G2 is selected, Reserved.
S25 Detect DTR Change S25 defines the minimum amount of time that DTR has to remain off (i.e., on-to-off-to-on transitions) before the modem will perform the function specified by ‘& Dn’command. A change in DTR that persists for a shorter time than the valued specified in S25 is ignored by the modem (see ‘&Dn’ command). Range: 0-255 (1/100 of a second) Default: 5 S26 RTS to CTS Delay Interval S26 is only used for synchronous operation.
Bit Value Description Bit 3,1,0 100 101 110 111 0 1 00 01 10 11 0 1 &Q4 is selected. Not used. Not used. Not used. &L0 is selected. (default) &L1 is selected. &X0 is selected. (default) &X1 is selected, &X2 is selected. Reserved. B0 is selected. B1 is selected. (default) Reserved. Bit 2 Bit 5,4 Bit 6 Bit 7 S30 Sleep Mode Timer S30 determines when the modem enters sleep or powerdown mode.
Sleep mode is disabled by setting S30 to a ‘0’. Range: 0-90 seconds S37 Maximum Line Speed Attempted This S-register selects the maximum line speed allowable (i.e., the modem will attempt to connect at this speed or fallback to a lower speed). Note that S37 has no effect during V.
S90 Disconnect Inactivity Timer This S-register sets the length of time, in minutes, that the modem will stay on-line /off-hook before disconnecting when no data is trans mitted or received. In data and fax modes, any data transmitted or received between the DTE-DCE interface will reset the timer. In all other modes except Telephone-emulation mode, any data transmitted will reset the timer. In Telephone-emulation mode,S90 is ignored (i. e.
S109 Line Speeds Permitted This bit mapped S-register selects all permitted line speeds. If the speed bit is set to a ‘1’, then the modern is permitted to connect at the specified speed. If the speed bit is set to a ‘0’, then the modem will never connect at the specified speed. Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6-7 Reserved 4800 7200 9600 12000 14400 Reserved Default: V.32 V.32 bis 52 S109=10 S109=62 Bit 2, 4, and 5 not supported.
4 - TESTING The modem provides five testing features to identify fault location when transmission quality is not good: local digital Ioopback, local analog loop back, local analog Ioopback with self-test, remote digital loopback, and remote digital loopback with self-test. These tests are initiated with the &Tn command described in Chapter 2. 4.1 Local Analog Loopback The local analog loopback test checks the integrity of the local computer or terminal and the local modem. During the test.
Fig.
Here, the test timer is disabled and the modem sets up an internal analog loop as shown in Figure 4-1. When the loopback is established, the modem goes on-line and the test message (any character you type) is looped back on the screen for verification. Finally, +++ returns the modem to the command state and &T0 ends the test and breaks the internal analog loop. The following command sequence is the same as the previous one except that the test timer is set to 60 seconds.
4.2 Local Analog Loopback with Self-Test The local analog loopback with self-test checks the integrity of the local modem. In this test, an internally generated data pattern of alternate binary ones and zeros (reversals) at the selected bit rate is looped through the internal analog loop inside the local modem to an internal error counter as shown in Figure 4-2. An error count of 255 indicates that 255 or more errors were detected.
Command: AT&T0< CR> (ends the test) Test result: 012 (12 errors were found during the test) Result code: OK 4.3 Remote Digital Loopback Fig.
the telephone line and the remote modem are all operating correctly. To start a remote digital loopback, first make sure the modem is on-line with a remote modem. Below, in the second command line, the timer is inactive, in the third command line, the test timer is activated for 60 seconds.
4.4 Remote Digital Loopback with Self-Test The remote digital loopback with self-test checks the integrity of the local modem, telephone line, and the remote modem. In this test the modem activates an internal test pattern generator. A test data stream is sent over the telephone line to the remote modem and looped through a remote digital loop to an internal error counter in the local modem as shown in Figure 4-4. Fig.
Escape command +++ (return the modem to the on-line command state) Result code: OK Command: AT\N1 ATS18=60&T3 Result: cursor shifts down one line (test starts) Test result: 000 (timer expires and no errors were found) Result code: OK 4.5 Local Digital Loopback Local digital loopback checks the integrity of the remote modem and the phone line if the remote user suspects either to be the cause of transmission errors.
Fig. 4-5 Data Path for Local Digital Loopback To start a local logical loopback first make sure that the modem is on-line with a remote modem. The modem can be in either the originating or answer modem.
Result Code: OK This command sequence returns the modem to the command state but does not break the established connection. It then disables the test timer and sets up an internal digital loop inside the modem. End the test when you confirm that the remote user has already finished by issuing: Command: AT&T0 Result Code: OK 4.6 Grant or Deny RDL Request from Remote Modem The modem can grant a request from the remote modem for a remote digital loopback test with the &T4 command (default).
5 - TROUBLESHOOTING GUIDE This chapter describes common problems in the installation, configuration and regular usage of your Fax/Data Modem. To test the Fax/Data Modem, a communication software package is needed and the package must include a mode that allows you to operate your Fax/Data Modem by directly issuing internal commands to the modem. Follow the procedures in the following sections to resolve these common problems: No Response From Your Modem 1.
your modem should be set to COM2 or COM4. Continue to the next step if the COM port address is OK. 4. Issue the command: AT&F&W , if a “0” or “OK result code is displayed on the screen, your modem is OK. Otherwise, contact your dealer for assistance. Your Modem Does Not Dial Out Make sure that your modem responds normally as described in section 4.1. If you can communicate through the keyboard, check whether the modem is properly connected to the phone line.
Fig.
Finding the Source of Transmission Errors A failure in modem communication is usually characterized by unacceptably high error rates or a total inability to communicate; it may be the fault of the local computer or terminal, the local modem, the telephone line, the remote modem or terminal. Figure 5-1 gives an algorithm for finding the source of errors. If you have any further questions or problems, please contact your dealer.
6- APPLICATION EXAMPLES 6.1 Dialing a Remote Modem Command line: ATDP9WT002, (886)-7128423 This command line instruct the modem to dial a remote modem through a PBX. The modem first use pulse dialing to dial 9 (the access mde of the PBX), wait for outside dial tone, and then use touch tone dialing to dial 002 once a one-second continuous dial tone is detected within 30 seconds, pause for 2 seconds (if S8=2) and then dial 8867128423. 6.
6.3 Manual Answer an lncoming Call Command line: ATA The factory setting of the S-register SO is S0=0. This condition disables the auto answer capability so that you must issue an ATA command to answer a call. At power up, your modem always monitors if there are incoming rings. If incoming rings are detected, your modem will display result codes on the screen as: RING RING Seeing that, you may issue the ATA command to answer the call.
This example also shows the insertion of space between two neighboring commands to make the command line more readable. 6.5 Voice to Data Switching Command line: ATA or ATX1D If you are talking with a remote modem user through the telephone set and want to initiate data communication with the remote modem, follow the procedure below: 1. You or the remote user issue an ATA command first to switch to data communication. 2.
A - TECHNICAL SPECIFICATIONS A.1 Features Speeds (bps) 300, 1200, 2400, 4800, 7200, 9600, 12000, 14400 (plus 19200, 38400, 57600 in data mode only) Protocols (Data) CCITT:V.32 bis, V.32, V.22 bis, V.22, and V.21. Bell: 212A and 103 (Fax) CCITT V.17, V.29, V.27 ter, and V.21 ch 2 Error Checking 100% reliable data transfer with V.
Modulation Operation Test Modes Audio Monitor Guard Tone 72 Full-or Half-duplex 14400 bps with 9600,4800,2400, and 1200 bps auto fall-back Analog Ioopback, local digital Ioopback, and remote digital Ioopback Built-in speaker, with software-controllable volume control 550/1800 Hz TECHNICAL SPECIFICATIONS - A
Compatibility: Data Fax CCITT V.32bis 14400/9600 bps, asynchronous CCITT V.32 9600/4800 bps, asynchronous CCITT V.22 bis 2400/1200 bps, asynchronous CCITT V.22 1200 bps, asynchronous CCITT V.21 300 bps, asynchronous Bell 212A 1200 bps, asynchronous Bell 103 300 bps, asynchronous CCITT V.17 14400/9600 bps, half-duplex CCITT V.29 9600/7200 bps, half-duplex CCITT V.
Pulse Dialing Specifications USA 74 International Make/Break Ratio 39/61 33/67 Break Length 61ms 67ms Dial Pulse Length 100m 100ms Dial Pulse Rate 1 Opps 10pps Interdigit Time 800ms 800ms TECHNICAL SPECIFICATIONS - A
B - Quick Reference Basic Data Modem ‘AT’ Commands Command A/ ** A Bn * Cn D En * Fn Hn In Kn Ln * Mn * Nn * On P * Qn * Sn Sn=x Sn? ? T * Default none none 1 1 none 1 1 0 0 none 2 1 1 0 none 0 none none none none none B - QUICK REFERENCE Function Repeat last command Answer Select CCITT or Bell Carrier control option Dial command Command echo On-line echo Switch hook control Identification/checksum SRAM buffer control Speaker volumn control Speaker control Connection data rate control Go on line Select
Command Vn * Xn * Yn * Zn &Cn * &Dn * &F &Gn * &Jn * &Ln &Mn * &Pn * &Qn * 8Sn * &Tn l &Vn &Un &Wn &Xn &Yn &Zn=x %En %Gn %Qn -Cn * * * * * Default 1 4 0 0 1 2 none o 0 0 0 0 0 0 0 0 0 0 0 0 none 1 0 none 0 Function Result code form Result code type Long space disconnect Recall stored profile DCD option DTR option Load factory defaults Guard tone option Auxiliary relay control Dial-up/leased line option Communication mode option Dial pulse ratio Communication mode option DSR option Self test commands Vi
V.
Dial Modifiers Command 0 to 9 A, B, C, D,*,# P R S=n T W , ! @ ; -() 78 Function Dialing digits Tone dial characters Pulse dial Reverse originate mode Dial NVRAM telephone number Tone dial Wait for dial tone Pause Flash hook Wait for quiet answer Return to idle state Ignored by modem QUICK REFERENCE - B
c - ASCII CODE TABLE Decimal Hex Value Decimal Hex Value Decimal Hex Value Decimal Hex Value C - ASCII CODE TABLE 79
