HOME OFFICE MODEM 33.6 Internal/External Fax Modem Advanced User’s Guide HOMEOFF.
HOME/OFFICE MODEM HOMEOFF.
Before You Begin your Installation The product you have purchased is designed to be easily installed into most IBM PC or compatible systems. Many products have large, easy-to-read legends to allow for the easy configuring of the product. This installation manual contains detailed instructions. Most included software has automatic installation programs to place the software correctly onto your computer.
Boca BBS 561-241-1601 1 4 7 8 2 5 3 6 9 Automated Fax Retrieval System 561-995-9456 Standard Free Technical Support 561-241-8088 Priority Service 900-555-4900 ($2 per minute) The Standard Free Technical Support number is for On-Line Support! quick answers to specific CompuServe: GO BOCA inquiries on product Internet: features and technical email: support@bocaresearch.com questions (call 561-241-8088; on the World-wide WEB: M-F, 8 am to 6:30 pm EST). http://www.bocaresearch.
Using the Boca Research HOME/OFFICE MODEM manual. This manual provides installation and operating instructions for the Boca HOME/OFFICE MODEM. The manual assumes the user has basic computer skills and is familiar with personal computers. Its primary purpose is to provide physical installation instructions and basic troubleshooting. All sections should be read carefully before beginning any installation procedures.
Contents Section One: Introduction ............................................ 7 Section Two: Package Contents .................................. 9 Section Three: External Modem Requirements and Status Indicators ..................................................... 11 Section Four: Internal Modem: Advanced Configuration for Windows 95 ........................... 13 Section Five: Troubleshooting .................................. 14 Appendix A: Technical Specifications ....................
Section One: Introduction The V.34 protocol offers the newest technology allowing faster and more reliable connections between modems. The Boca HOME/OFFICE MODEM is based on the Rockwell chip set. This modem supports the highest possible speeds today. Features n Highest supported data transmission rates by the V.34 (33.6Kbps) standard; 14.4Kbps send/receive fax. n 100% compatible with the Hayes ‘AT’ command set. n Auto-dial and auto-answer; tone or pulse dialing.
Installation Hints Your HOME/OFFICE MODEM has been pre-set at the factory for optimum performance. All defaults are set to allow the modem to negotiate the best possible connection with highest quality, data compression, and error correction. Because of these factory defaults, the suggested initialization (INIT) string is: ATZ. If you want to custom configure your stored profiles, we suggest that you always start out with an AT&F&C1&D2 before customizing other commands.
Section Two: Package Contents This section explains how to connect the Boca Research HOME/OFFICE MODEM to your computer. External Modem Verify that your external modem package contains the following items: AC POWER ADAPTER EXTERNAL MODEM 12 12 RJ-11 CABLE ADVANCED USERS GUIDE 12 12 COMMUNICATIONS SOFTWARE & MANUAL (Phone cable configuration will vary for international settings.) If any items are missing or damaged, contact the vendor from whom you purchased the modem for assistance.
Internal Modem Verify that your internal modem package contains the following items: INTERNAL HOME/O FFICE MODEM COMMUNICATIONS ADVANCED SOFTWARE & MANUAL USERS GUIDE 12 12 11 RJ-11 CABLE (Phone cable configuration will vary for international settings.) If any items are missing or damaged, contact the vendor from whom you purchased the modem for assistance HOME/OFFICE MODEM HOMEOFF.
Section Three: External Modem Requirements and Status Indicators The external version of the HOME/OFFICE MODEM has few requirements and is easy to use. Be sure to read the information in the Appendix about connecting to the phone company. In addition, note the following: n The communication settings are controlled by the software that manipulates the serial interface present in your system. The external modem is connected to that interface.
Status Indicators Indicator Definition Status TM Test Mode FLASHES when modem is in test mode and if any errors are detected. AA Auto Answer ON when in Auto Answer mode and when online with the host modem. HS High speed ON when the modem is powered on or communicating with another modem at 4800bps or faster. OH Off Hook ON when the modem takes control of the telephone line to establish a data link. SD Send Data FLASHES when a data bit is sent to the modem by the computer.
Section Four: Internal Modem: Advanced Configuration for Windows 95 The Internal Boca Modem you have just purchased is an 8bit modem that can use IRQs 3, 4, 5, or 7. If you are reading this section, it is probably because Windows 95 has already assigned all of the above-mentioned IRQs to other devices in your system. In order for you to complete installation of the modem, you must first make one of the IRQs in the group 3, 4, 5, and 7 available.
Section Five: Troubleshooting This section lists common problems that may be encountered and their possible solutions. SYMPTOM No dial tone. Modem will not connect to another modem. No response when you type in AT commands POSSIBLE REMEDY n Verify that you have cables plugged in correctly. n Connect a telephone set directly to the wall jack and check for a dial tone. If no dial tone is heard, the telephone line is not working. Contact the telephone company.
SYMPTOM No response when you type in AT commands (contd) POSSIBLE REMEDY n Verify that the communication software is set to the same communications port where your modem is attached (e.g., COM1, COM2). Check IRQ settings in your software and on the modem. n Check your serial cable connection (EXTERNAL MODEL ONLY). n Try typing AT&F to reset the modem to its factory defaults. n Move the modem to another serial port (power down the host computer first).
SYMPTOM POSSIBLE REMEDY Garbled characters (contd) The modem does not answer an incoming call. Modem disconnects while on-line. n Power down your system (INTERNAL) and re-run your communications software. Check software settings. n Exit the communications program and restart it. n You may not have enabled autoanswer. Use your software to enable this function. n If you have an answering machine, it may be answering before the modem can.
SYMPTOM POSSIBLE REMEDY I am having trouble getting my init string to work. n Init strings are primarily personal preferences. Use the most basic one that can get the job done. See Installation Hints on page 8. An &Q6 (which disables error control) is optional. Connection Errors n Try connecting at a lower speed (e.g., 9600 or 2400bps). n Turn off error correction/ compression with an AT&Q6%C0 command. n Noisy/poor line conditions may prohibit connection.
SYMPTOM POSSIBLE REMEDY Problem Connecting to Online subscription services. n Some on-line services require that your modem be configured to run with error correction and data compression turned OFF. The easiest way to accomplish this is by using the command AT&Q6 and setting the communication software to the correct baud rate for the service you are calling (e.g., 2400, 9600bps).
Appendix A: Technical Specifications Modem Data Rate: 33.6K, 28.8K, 26.4K, 24K 21.6K, 19.2K, 16.8K, 14.4K, 12K, 9600, 7200, 4800, 2400, 1200, or 300bps Fax Data Rate: 14.4K, 12K, 9600, 7200, 4800, 2400bps Protocol Compatibility: CCITT: (ITU-TSS) CCITT: V.34 (33.6Kbps), V.32bis (14.4Kbps), V.32 (9600bps), V.42, V.22 (2400bps), V.21 (1200bps) Bell: Bell 212A (1200bps), Bell 103 (300bps) Rockwell: V.FC Fax Modulation Protocols V.17 V.29 V.27 V.21 (14.
Appendix B: Compliance Information FCC Statement: “This device complies with part 15 of the FCC rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference. (2) This device must accept any interference received including interference that may cause undesired operation. THIS UNIT COMPLIES WITH FCC PART 68 AS OF DATE OF MANUFACTURE.
Notification to the Telephone Company Notification to the telephone company is no longer required prior to connecting the registered equipment but upon request from the telephone company the user shall tell the telephone company which line the equipment is connected to as well as the registration number and the ringer equivalence of the registered protective circuitry. In most, but not all areas, the sum of all RENs should be 5.0 or less.
Changes in Telephone Company Equipment or Facilities The telephone company may make changes in its communications facilities, equipment, operations, or procedures, where such action is reasonably required and proper in its business. Should any such changes render the customer ’s terminal equipment incompatible with the telephone company facilities, the customer shall be given adequate notice to make modifications to maintain uninterrupted service.
malfunction, may give the telecommunications company cause to request the user to disconnect the equipment. Users should ensure, for their own protection, that the electrical ground connections of the power utility, telephone lines, and internal metallic water pipe system, if present, are connected together. This precaution may be particularly important in rural areas.
DECLARATION OF CONFORMITY (In accordance with EN 45014) We, Boca Research, Inc. 1377 Clint Moore Road Boca Raton, FL 33487 declare under our sole responsibility that the product, Type of Equipment: Optical Modems Model Numbers: ‘MV.34XXI, MV.34XXE’, ‘MV.
WARNING/ATTENTION #1“CAUTION: THIS MODEM CARD IS INTENDED TO BE INSTALLED IN CSA CERTIFIED EQUIPMENT IN THE FIELD BY THE USER IN THE MANUFACTURER’S DEFINED OPERATOR ACCESS AREA. CHECK THE EQUIPMENT OPERATING/ INSTALLATION INSTRUCTIONS AND/OR EQUIPMENT MANUFACTURER TO VERIFY/CONFIRM IF YOUR EQUIPMENT IS SUITABLE FOR USER-INSTALLED APPLICATION CARDS.
NOTES FOR USE OF THIS DEVICE IN NEW ZEALAND • The grant of a Telepermit for a device in no way indicates Telecom acceptance of responsibility for the correct operation of that device under all operating conditions. • This equipment shall not be used in any manner which could constitute a nuisance to other Telecom customers.
Appendix C: Modem Command Reference In most cases, your communications software will set and control the operation of your modem. Following is a brief survey of the most commonly used Hayes-compatible AT commands for use with your modem. In addition, we’ve also provided information on extended AT command sets, SRegisters, and commands and registers for high-level protocols such as MNP, V.42/V.42bis, and V.32/V.32bis. It will rarely be necessary to use ‘AT’ commands and SRegisters in command mode.
Example: ATH or ATH0 tells the modem to disconnect Extended commands were developed to provide greater functionality and control over modem operations. Their format is the same as the basic command except that an additional parameter is required following the AT prefix and before the numerical parameter.
Example: S-Register 6, or S6=n, defines the length of time the modem will wait for a dial tone. In this case the acceptable range is 3-6 (in seconds) with a default value of 5. With S6=3, the modem will wait three seconds for a dial tone when going off-hook before dialing the first digit of its telephone number. Data Communication Protocols This can be more than a little confusing. These protocols represent various domestic and international standards which enhance modem performance and reliability.
V.21 The CCITT standard for 300bps communications. Domestic modems follow the Bell 103 standard, but V.21 can accept international calls at 300bps. V.22 The CCITT standard for 1200bps communications. The domestic equivalent is the Bell 212A standard. V.22bis The CCITT standard for 2400bps. V.23 CCITT for 1200bps with a 75bps back channel. This is mostly used in Europe and South America. V.24 CCITT serial interface standard (EIA/RS232-D). V.
BASIC AT COMMANDS (default values are highlighted) NOTE: AT command functionality may vary in international settings. Command definitions listed in subsequent pages reflect domestic (U.S.) functionality. Command AT ATA A/ Description Attention characters Answer command Re-Execute last command Dial Modifiers Dial ATD Options 0-9 L P* T W , @ ! ; ^ S=n Description DTMF digits Re-dial last number. Pulse (rotary) dial. 10 pulses per second. Touch tone dial (DTMF). Wait for dial tone for 1-255 seconds.
Command Description Command Character Echo ATE0 Disables echoing of the commands to the screen. ATE1 Enables echoing of the commands to the screen. (default) Switch Hook Control ATH0 Instructs modem to go on-hook. ATH1 Instructs modem to go off-hook. Identification ATI0 Displays the product identification code. ATI1 Displays the checksum. ATI2 Displays ROM checksum as OK or ERROR. ATI3 Displays the firmware revision level. ATI4 Reports OEM-defined identifier string. ATI5 Reports country code.
Command Description Automode enable ATN0 Requires speed of the connection be that specified by the value of S37. ATN1 Permits handshaking at any speed supported by both modems. (default) Return to on line state mode ATO0 Switches the modem from command mode to online mode without dialing. ATO1 Switches from command mode to on-line mode and initiates an equalizer retrain sequence. d Mode responses ATQ0 Enables result codes to be issued to the screen.
Command Description Extended result codes ATX0 Disables monitoring of busy tones unless forced otherwise by country requirements; sends only OK, CONNECT, RING, NO CARRIER, ERROR and NO ANSWER result codes. ATX1 Disables monitoring of busy tones unless forced otherwise by country requirements; sends only OK, CONNECT, RING, NO CARRIER, ERROR, NO ANSWER and CONNECT XXXX result codes.
Extended AT Commands Command Description Data carrier detect (DCD) signal AT&C0 Forces DCD signal to be on at all times. (default) AT&C1 DCD on indicates presence of data carrier. Data terminal ready (DTR) signal. Interprets the ON to OFF transition of the DTR signal from the DTE according to the &Q settings. AT&D0 AT&D1 AT&D2 AT&D3 AT&F &Q0,5,6. DTR ignored. &Q1,4. Modem hangs up; auto answer not affected. &Q2,3. Modem hangs up; auto answer inhibited. (default) &Q0,1,4-6.
Note on Flow Control. XON/XOFF is a software-based flow control method, using standard ASCII control characters to pause or resume data transmission. RTS/CTS pacing, a hardware-based method, uses an electrical signal. Signals are exchanged as follows: RECEIVER CTS ON CTS ON CTS OFF Command è ç è TRANSMITTER START SENDING RTS ON (ready to send) RTS OFF (stop sending) Description Select pulse dial make/break ratio AT&P0 Selects a make/break ratio of 39/61 at 10pps. US and Canada.
Command Description Test and diagnostics AT&T0 Terminates any test in progress. AT&T1 Executes the local analog loopback test. AT&T3 Executes the local digital loopback test. AT&T4 Enables the modem to accept a request from a remote modem for a digital loopback test. (default) AT&T5 Instructs the modem to deny a request from a remote modem for a digital loopback test. AT&T6 Executes the remote digital loopback test. AT&T7 Executes the remote digital loopback test with a self test.
MNP Operation The HOME/OFFICE MODEM supports all of the preceding classes. The following AT Commands apply to the MNP protocol. Default values are highlighted. Maximum MNP Block Size. Use this command to transmit smaller blocks of data in a reliable data link connection. AT\A0 AT\A1 AT\A2 AT\A3 set maximum block size to 64 characters. set maximum block size to 128 characters. (DEFAULT) set maximum block size to 192 characters. set maximum block size to 256 characters. Transmit Break.
Break Control. Determines the modem response when a BREAK is received from the DTE or the remote modem. The values of the parameters vary based on the three following conditions: (1) When a break is received from the DTE during NORMAL or MNP mode: AT\K0, 2, 4 modem enters command mode 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 the buffers, but sends a break to the remote modem.
Error Correction Operating Mode. Selects the operating mode the modem uses while connected. AT\N0 AT\N1 AT\N2 AT\N3 AT\N4 AT\N5 NORMAL (speed buffering) mode. DIRECT (pass-through) mode. RELIABLE LINK mode. Specifies error correction for the modem-to-modem connection AUTO-RELIABLE LINK mode. Attempts errorcorrection connection but will fall back to normal mode if unable to establish an MNP link. (default) LAPM error correction mode. MNP error correction mode HOME/OFFICE MODEM HOMEOFF.
AT Commands for V.42/V.42bis The following AT commands apply to the V.42/V.42bis protocol: Compression Control. Determines whether or not modem will use data compression. AT%C0 AT%C1 AT%C2 AT%C3 disables data compression enables MNP5 data compression negotiation enables V42bis data compression enables both V.42bis and MNP5 data compression (DEFAULT) Auto-retrain. Determines whether or not the modem automatically monitors the line quality and requests a retrain when necessary.
AT%Q 009 = -9 dBm, 010 = -10dBm, etc. all the way to 043 (-43 dBm) Report Line Signal Quality. Returns a “high-order” byte of the calculated EQM (“eye quality monitor”). This can range from 0 to 255. When the value is 8 or greater, the modem will automatically retrain if enabled by the AT%E1 command. The value for a normal connection ranges from 0 to 2 and approaches 8 for a progressively poorer connection. Returns an OK result code. 000 to 007 no retrain 008 to 255 retrain performed if enabled by %E1.
AT+MS Command (Modulation Select) This extended format command selects the modulation, optionally enables or disables automode, and optionally specifies the lowest and highest connection rates using from one to four subparameters.
Reporting Supported Options The modem can send a string of information to the DTE consisting of supported options using the following commands. +MS=? The response is: +MS: (list of supported values), (list of supported values), (list of supported values), list of supported rate values) Example: +MS: (0, 1, 2, 3, 9, 10, 11, 64, 69, 74), (0,1) (300-28800), (30028800) Subparameter Definitions 1.
Modulation Selected 0 1 2 3 9 10 11 V.21 V.22 V.22bis V.23 V.32 V.32bis V.34 64 69 74 Bell 103 Bell 212 V.FC Possible rates (bps) 300 1200 2400 or 1200 1200* 9600 or 4800 14400, 12000, 9600, 7200, or 4800 33600, 28800, 26400, 24000, 21600, 19200, 16800, 14400, 12000, 9600, 7200, 4800, or 2400 (DEFAULT) 300 1200 28800, 26400, 24000, 21600, 19200, 16800, 14400 * For V.23, originating modes transmit at 75bps and receive at 1200bps; answering modes transmit at 1200bps and receive at 75bps.
2. =an optional numeric value which enables or disables automatic modulation negotiation. Options are: 0 1 Option Selected Automode disabled Automode enabled The default value is 1, which enables automode. Note, however, there are modulations for which there is no automatic negotiation (e.g., Bell 212 (=69). For = 0 (automode disabled, i.e., fixed modulation): a.
Example: +MS=11,0,16800,16800 selects V.34 16800bps fixed mode (no comparable S37 command). +MS=10,0,12000,12000 selects V.32bis 12000bps fixed mode (same as N0S37=10). For = 1 (automode enabled; i.e., automatically selected speed and modulation). a. If is greater than the highest rate supported by the modulation specified by , the modem automodes down from the highest rate of selected modulation. Example: +MS=10,1,1200,24000 selects automoding down from V.32bis 14400bps.
S-Registers This section defines the purpose of the modem registers, and sequentially lists the registers and describes their functions. These registers affect various operating characteristics and allow you to obtain information about the modem, as well as test the modem. Each register has a factory-set value, which you can read or change to fit your needs. Reading a Register Value To read the current value of a register, type: AT Sn? [ENTER], where n is a register number.
The following table lists the modem’s registers and their functions. Reg. S0 S1 S2 S3 S4 S5 S6 S7 S8 S9 S10 Range 0-255 0-255 0-255 0-127 0-127 0-255 2-255 1-255 0-255 1-255 1-255 Units Default rings 0* rings 0 rings 43 ASCII 13 ASCII 10 ASCII 8 seconds 2 seconds 50 seconds 2 seconds 6/10 seconds 14 (1.4) Definition Auto-answer Count incoming rings Escape character value. Carriage return character. Line feed character. Backspace character. Wait time for Blind Dialing. Wait for carrier after dial.
Reg. S24 S25 S26 S27 S28 S29 S30 S31 S32 S33 S34-35 S36 S37 Range Units Default Definition 0-255 seconds 0 Sleep Inactivity Timer. 0-255 seconds 5 Asynchronous DTR Delay. 0-255 seconds 1 RTS to CTS Delay Interval. Bit Mapped 9(09h) Bit mapped registers. Bit Mapped 0 Bit mapped registers 0-255 ms 10 Flash Dial Modifier Time. 0-255 seconds 0 Disconnect Inactivity Timer. Bit Mapped 2 0-255 ASCII 17(11h) XON Character. 0-255 ASCII 19(19h) XOFF Character. Reserved.
Reg. S38 Range Units Default 0-255 seconds 20 S39 S40 S41 S42-45 S46 Bit Mapped Bit Mapped Bit Mapped 3 104(68h) 3 136 or 138 138 Definition Delay Before Forced Hangup. Bit Mapped Registers. Bit Mapped Registers. Bit Mapped Registers. Reserved. Data Compression Control. NOTE: 136 enables error correction with no compression; 138 enables error correction WITH compression. S48 0, 7, 128 7 V.42 Negotiation.
Reg. Range Units S95 Bit-Mapped Default 0 Definition Extended Results Codes. NOTE: Bit values are defined as follows for S95: 0 = CONNECT CODE indicates DCE speed instead of DTE speed. 1 = Append ARQ (automatic repeat request) to verbose CONNECT XXXX result code if protocol is other than none. 2 = Enable CARRIER XXXX result code. 3 = Enable PROTOCOL XXXX result code. 5 = Enable COMPRESSION result code. Bits 4, 6, and 7 are reserved. HOME/OFFICE MODEM HOMEOFF.
Result Codes Result Code Numeric Value Description OK 0 Modem successfully executed a command line. CONNECT 1 Connection made at 300 bps. RING 2 Modem detected an incoming call. NO CARRIER 3 Modem lost or could not detect a remote carrier signal within the Register S7 time. ERROR 4 Modem found an error in the command line. CONNECT 1200 5 Modem established a connection 1200 at 1200bps. NO DIALTONE 6 Modem did not detect a dial tone within 5 seconds after going off-hook.
Result Code Numeric Value Description CONNECT 7200 13 Connected as data modem during an answer. CONNECT 12000 14 Connection made at 12000 bps. CONNECT 14400 15 Connection made at 14400 bps. CONNECT 19200 16 Connection made at 19200 bps. CONNECT 38400 17 Connection made at 38400 bps. CONNECT 57600 18 Connection made at 57600 bps. CONNECT 115200 19 Connection made at 115,200 bps. CONNECT 22 Modem returns this result code when upon 75TX/1200RX establishing a V.
Result Code DELAYED Numeric Value Description 24 For X4; when a call fails to connect and the number dialed is ‘delayed’ due to country blacklisting requirements. BLACKLISTED 32 For X4; when a call fails to connect and the number dialed is considered ‘blacklisted’. FAX 33 A fax modem connection is established. DATA 35 A data modem connection is established. CARRIER 300 40 Carrier rate of 300 bps. CARRIER 1200/75 44 V.23 backward channel has been detected. CARRIER 75/1200 45 V.
Result Code Numeric Value Description CARRIER 12000 51 Carrier rate of 12000 bps. CARRIER 14000 52 Carrier rate of 14400 bps. CARRIER 16800 53 Carrier rate of 16800 bps. CARRIER 19200 54 Carrier rate of 19200 bps. CARRIER 21600 55 Carrier rate of 21600 bps CARRIER 24000 56 Carrier rate of 24000 bps CARRIER 26400 57 Carrier rate of 26400 bps. CARRIER 28800 58 Carrier rate of 28800 bps.
Result Code Numeric Value Description COMPRESSION: 69 NONE The modem has connected without data compression and COMPRESSION message reporting has been enabled. PROTOCOL: NONE* 76 Modem has connected without any form of error connection. PROTOCOL: LAPM* 77 Modem has connected in the V.42 LAPM mode of error correction. PROTOCOL: ALT* 80 Modem has connected in the MNP mode of error correction. PROTOCOL: 81 ALT* CELLULAR Modem has connected in the MNP10 mode.
Appendix D: Servicing Your Boca Product If your HOME/OFFICE MODEM requires service, first contact the authorized dealer from whom you purchased the modem. If the dealer is unable to assist you, and you must contact Boca Research, Inc., please follow the instructions below. Our electronic BBS is available 24 hours a day at (561) 241-1601 and will support data transmission speeds up to 28.8Kbps with settings of N, 8, 1.
If you suspect a problem with a specific program or software package, make note of the name, version or release number, and manufacturer of the software. 2. Call our Technical Support Department between the hours of 8:00 a.m. and 6:30 p.m. EST Monday through Friday at (561) 241-8088. A technician will be available to discuss the problem(s) you are experiencing. If factory service is required, you will be given a Return Merchandise Authorization (RMA) number.
n n n n n the HOME/OFFICE MODEM (board or external case only) a copy of the original invoice your return street address (for UPS purposes) phone number the RMA number mentioned above Package the product securely in a container equivalent to the original packaging, and insure the package to protect against loss or damage during transit. Shipping charges must be prepaid; C.O.D. shipments will not be accepted. Please use the address below for all correspondence: Boca Research, Inc.
Appendix E: Warranty Information Limited Warranty Boca Research, Inc. (BRI) warrants to the original buyer of this BRI product that the hardware is free of defects in materials and workmanship for a period of five (5) years from the date of purchase from BRI or its authorized dealer. Should the product fail to be in good working order at any time during the five-year period, BRI, will at its option, repair or replace this product as described below.
Glossary A algorithm. A formula or procedure which employs various methods defining how data is to be used to give a prescribed result. analog signals. Signals which can vary over a continuous range (e.g., the human voice over conventional telephone lines). Analog circuitry is more subject to distortion and noise, but it is more capable of handling complex signals than are digital signals which can have only discrete values. ARQ. Automatic Retry ReQuest for retransmission.
bit-mapped registers. An S-register which contains multiple bitoriented values. Example: the value of S22 is the sum of the bit values which you select (bits 0-1: speaker volume/value: 0-3; bits 2-3: speaker control/value: 0-3; bits 4-6: limit result codes/value: 0, 4-6, 7). blind dialing. An automated process whereby the modem goes offhook and dials without waiting for a dial tone. This is prohibited in many countries. block transfer control.
DCE. Data Communications Equipment. The local and/or remote modem. A DCE is usually connected to a DTE. DTE. Data Terminal Equipment. The computer or terminal, either local (yours), or the remote (the one you’re communicating with). A DTE is usually connected to a DCE. DTR. Data Terminal Ready. The computer issues this signal to the attached modem indicating that it is ready to receive data. data compression.
extended AT-command. Extended commands were developed to provide greater functionality and control over modem operations than is available from the basic AT command set. F fax mode. The modem is in fax mode when, through use of fax communications software, it can send and receive faxes, print and display fax files, convert files to fax-files, and set certain fax-related features. Note: the modulation protocol used by the modem in fax mode is also different from the usual data mode modulation.
L LAPM. Link Access Protocol Modem. A V.42 ARQ type of error correction protocol which is controlled by S-Register 46, where LAPM may be activated with or without V.42bis data compression. leased line. Also referred to as a private line. A leased line is obtained from a communications company (carrier) to provide a transmission medium between two points. The line consists of a permanent dedicated circuit between two points, or to set of previously arranged points.
modulation handshake. Also referred to as Automode Enable and is controlled by the ATN command. This determines whether or not the modem must connect at a particular speed, or allow connection at any speed supported by both modems. N negotiation fallback. Controlled by S-Register 36 as part of the V.42 protocol. Setting this register indicates what action to take when a desired connection cannot be made (e.g., hang-up, direct mode connect, normal mode connect). non-volatile RAM. Also NVRAM.
retrain. An adjustment process performed when one of the modems detects signal distortion or line noise which threaten data integrity. RTS/CTS. Request to Send/Clear to Send. RTS and CTS are two control signal lines between the modem (DCE) and terminal (DTE) which allow the terminal to control the flow of information. See also flow control. S sleep inactivity timer. Determines the length of time the modem operates in normal mode with no activity before entering low-power “sleep” mode.
HOMEOFF.
Manual Part No. 9378 Rev. 1.0 HOMEOFF.
