******************************************************************************** SUPRAFAXMODEM AND SUPRACOMCARD REFERENCE MANUAL REVISED MAY 1993 PART # 70-0087-1A SupraCOMcard and SupraFAXModem are trademarks of Supra Corporation. All other trademarks belong to their respective owners. Manual Copyright 1993 Supra Corporation. Supra Corporation - World Headquarters 7101 Supra Drive SW, Albany, OR 97321 General: (503) 967-2400 Fax: (503) 967-2401 Sales: 7:00am - 5:00pm PST, M-F (503) 967-2410 (800) 727-8772 Supra Tech Support: 8:00am - 4:30pm PST, M-F (503) 967-2440 GENERAL (503) 967-2490 PC (503) 967-2492 MAC (503) 967-2493 AMIGA Supra BBS.... ....(503) 967-2444 8 lines 24 Hours v.32bis v.42bis LAPM 2-5 Supra FaxBack Service 503-967-0072 CompuServe.......76004,565 BIX..............SupraCorp America Online...SupraCorp2 GEnie............SupraTech AppleLink........D2456 UseNet EMail.....supratech@supra.com ***************************************************************************** INTRODUCTION ***************************************************************************** Welcome to the Reference Manual. You should have already read the Getting Started manual for information on setting up your modem and using it for basic tasks. Now that you are familiar with your modem's basic operations, you are ready to learn more about its advanced capabilities. This manual provides general information on your modem's fax capabilities.It does not describe the fax commands or explain how to program the modem's fax functions, because your fax software should provide all the functions you need. Refer to your fax software manual and Chapter 1 of this manual for additional information on the modem's fax features. This manual also contains detailed information about your modem's data communications capabilities and how to use them. It includes detailed instructions on using your modem's "AT" commands to perform tasks your software can't,and explains the modem's error correction and data compression features.It also includes a troubleshooting chapter to help you if you are experiencing problems and a glossary of telecommunications terms that should help you understand this sometimes confusing technology. This manual does not explain fax or telecommunications software.Please refer to your software manuals for information on using a particular program. Your modem and software manuals should help you with any questions you have about using your modem, but if you need further assistance, please consult the resources listed in Appendix G or contact us directly. Enjoy your modem! ***************************************************************************** TABLE OF CONTENTS ***************************************************************************** INTRODUCTION 1 FAX ISSUES Group 3 CCITT Protocols and Rates Class 1, 2, & 2.0 Fax Commands Fonts Used When Faxing Software Authors 2 USING AT COMMANDS Issuing Commands Yourself (Terminal Mode) Command State & Online State Escape Code (+++) Command Line Syntax Command Line Buffer Result Codes 3 USING MNP, V.42BIS, & FLOW CONTROL Start with the Basics How Error Correction & Data Compression Work Error Correction Data Compression Connection Rates How the Modem Determines Connection Speed & Protocol After Connecting Connection Types \N1 Direct Connection \N Normal Connection \N2 & N4 Reliable Connection \N3 AutoReliable Mode Flow Control The Configurations Most People Need Using Xmodem, Ymodem, or Pre-Compressed Files MNP 5 Data Compression V.42bis Data Compression Error Correction 4 DIALING Using the Dial Command Dialing from a Telephone Storing a Telephone Number Automatic Pulse Dialing If Telephone System Does Not Support Touch Tones Disabling Call Waiting 5 ANSWERING Answering Calls Identifying The Source of an Incoming Call (Caller ID) What is Caller ID? Potential Applications Can You Use Caller ID? Software Options Caller ID AT Commands How to use Caller ID with Telecommunications Software Distinguishing Between Incoming Voice, Fax, and Data Calls (Silent Answer & Adaptive Answer) Silent Answer (Optional Feature #141) What is Silent Answer? Do You Need to Use Silent Answer? Can You Use Silent Answer? Adaptive Answer What is Adaptive Answer? Can You Use Adaptive Answer? Software Issues Software That Supports Silent Answer/Adaptive Answer Software That Does Not Support Silent Answer/Adaptive Answer 6 CONNECTING Bell & CCITT Protocols Connection Rates Connection Types 7 CREATING CUSTOM MODEM CONFIGURATIONS Do You Need to Configure Your Modem? Factory Default, Active, & Stored Configurations Creating a Custom Configuration AT Commands Used When Creating a Custom Configuration AT Commands for Changing S Registers Directly &F, &F1, &F2: The Factory Configurations 8 SOLVING PROBLEMS Part 1: Symptoms, Sources, & Solutions First, Double Check Your Equipment & Configuration Problems Encountered While Offline Problems When Trying to Connect Problems While Connected Part 2: Additional Troubleshooting Information High Speed Communication Problems Serial Port Speed Problems Faster UART Chip for PC Compatibles Used with External Modems Slow Downloads Multitasking Flow Control & Hardware Handshaking Cables on External Modems Line Noise Line Noise Problems on Fax Calls Line Noise Problems on Data Calls Where Does the Problem Originate? Line Noise Checklist Understanding the Line Noise Checklist:Rate Renegotiation Commands & S Registers Miscellaneous Troubleshooting Issues What ROM Version Do You Have? Power Supplies Compatibility With Other Modems/Older Modems A OPTIONAL FEATURES 101 Fax Class 1 104 Fax Class 2 105 Fax Class 2.0 115 CCITT V.17, 14,400 bps Fax 120 Worldwide Support 121 CCITT V.23 122 CCITT V.25 123 Blacklisting 124 Access Security Storing Passwords & Callback Numbers (*Pn) Listing Passwords & Callback Directories (*L) Requesting Secure Access Mode (*R) Enabling Secure Access & Requesting Password (*C) Exiting Secure Access (E) 140 CCITT V.32bis, 14,400 bps Data 141 Silent Answer 142 Caller ID 143 MNP 10 144 MNP Cellular 145 AutoSync 146 Enhanced Configuration Display 160 Voice Processing B AT COMMAND DESCRIPTIONS C RESULT CODES Result Code Commands Sample Result Codes Which Result Codes Should You Use? Complete List of Possible Result Codes D S REGISTER DESCRIPTIONS E RS-232C PIN ASSIGNMENTS F FCC & DOC RULES Federal Communications Commission (FCC) Canadian Department of Communications (DOC) G RESOURCES GLOSSARY ***************************************************************************** CHAPTER 1: FAX ISSUES ***************************************************************************** The most important thing you need to know about fax standards (sometimes called protocols) is that the faxmodems and machines you connect to must support the standards you use. GROUP 3 Group 3 is a standard that lets most modern fax devices (including your modem) communicate with each other. It specifies image resolution, complex data compression, and other features. The vast majority of fax devices in use today support Group 3. CCITT PROTOCOLS AND RATES The CCITT protocols (defined by the international CCITT standards committee) are standards that let fax devices (faxmodems and fax machines) communicate at specific rates. CCITT defines communication at various speeds up to a maximum of 14,400 bps communication, CCITT V.29 defines speeds up to 9600 bps, and CCITT V.27ter defines speeds up to 4800 bps. Most fax devices today communicate at 9600 bps, but because of relatively recent technological advances, 14,400 bps fax connections will become much more common in the near future. CLASS 1, 2, & 2.0 FAX COMMANDS Class 1, 2, and 2.0 are the command sets used by fax software to control a faxmodem. These fax commands are invisible to you when you use fax software. Class 1 is an officially approved standard. Class 2 is a defacto standard that has never been approved. A new, approved version of Class 2, called Class 2.0, may be available in the future. These fax command sets are optional features that are only available on select modem models. Class 1 is option #101, Class 2 is option #104, and Class 2.0 is option #105. The I10 command tells which optional features your modem supports Do you need to specify Class 1, 2, or 2.0? The answer is usually no, but it depends on your fax software. Some fax software automatically determines which class to use. For other software, you need to select the predefined configuration that came with your modem or software. The predefined configuration will automatically set the modem to the appropriate class. If your software comes with this type of configuration, it should be fairly simple to install. If you need help, your fax software manual should be able to help you. Less frequently, some fax software does require you to select either Class 1 or Class 2. If you find that you have problems using one, you may want to try using the other. FONTS USED WHEN FAXING To ensure the best quality fax output in Macintosh and Windows environments, it is very important that you use both screen and printer fonts, and if applicable, also use Adobe Type Manager (ATM) or TrueType. A common mistake is using a font that is built into your printer for which you have a Screen font, but not a Printer font. The type will appear fine on your screen but be faxed in blocky letters because it used the Screen font to create each character. The solution is to use a font with both Printer and Screen fonts or to obtain the printer font you need. SOFTWARE AUTHORS Available fax software should provide all the fax functions you need.However, if you are an advanced programmer and want to write fax software, you can obtain information about fax commands from the following sources. (This information is provided for software authors, not novices. Most users will not find it helpful.) * The following publications, available from Global Engineering Documents, 714-261-1455, 2805 McGraw Ave., Irvine, CA 92714. Additional phone numbers: 800-624-3974 in U.S., 800-854-7179 outside U.S. - EIA/TIA-578 (Class 1) - EIA/TIA-592 (Class 2) - CCITT Volume VII, Fascicle VII.3, Recommendations T.0-T.63 * The following Macintosh-specific tool, available from STF Technologies, 816-463-2021, Junction I-70 and Highway 23, Concordia, MO 64020: The STF Developer's Kit. ***************************************************************************** CHAPTER 2: USING AT COMMANDS & RESULT CODES ***************************************************************************** When you use your telecommunications software to perform a task (such as dialing a phone number), it uses the modem's AT commands to perform the task. It is usually easier to let your telecommunications software issue the commands for you than it is to issue the AT commands yourself. When your telecommunications software can't perform a task (or you don't want it to), you'll issue the AT commands yourself. These commands can be used to perform various tasks, from hanging up to changing your modem's speaker volume Various chapters in this manual explain how to use the AT commands to accomplish specific tasks. The rest of this chapter explains how the AT commands work, and Appendix B explains them all in more detail. ISSUING COMMANDS YOURSELF (TERMINAL MODE) To issue AT commands yourself, you must be in your software's "terminal mode" -- also called "local" mode. In this mode, the commands you type go to the modem rather than to your software or the remote computer Some software is in terminal mode as soon as you start the program. If the modem responds with the OK result code when you type the following, you are in terminal mode and ready to issue commands ([CR] represents a carriage return): AT [CR] If you are not in terminal mode, refer to your software manual to determine how to get there. COMMAND STATE & ONLINE STATE The modem can operate in either the command state or the online state: * When you first turn your modem on, it is in command state. It must be in command state to issue AT commands. * When your modem connects to another modem, it automatically changes to the online state. Your modem must be in the online state for data to be transmitted. If you're connected to a network, Bulletin Board System, or other remote computer (i.e. you're online) you can transmit data, but you must change to command state to send AT commands. To switch from one state to the other, use the methods below. * To switch from online to command state, type the escape code (+++) as explained below. This automatically puts you in terminal mode, ready to type commands. * To switch from command state to online state, issue the O (online), A (answer), or D (dial) command (in other words, go back online, answer a call, or dial a number). The O, A, and D commands are described in Appendix B. ESCAPE CODE The escape code is a string of three ASCII plus signs (+++) preceded and followed by a "guard time" during which no other data is transmitted. It is used to leave the online state without hanging up. To use it, do the following: 1. Send a character. 2. Do not transmit any data for a period equal to the guard time.The default setting for the guard time is 1 second. 3. Type the escape code quickly. Do not follow with a carriage return. 4. Do not transmit any data for another period of time equal to the guard time. The modem responds to these steps with the OK result code. If it doesn't, either it received data during the guard time or the escape code was typed too slowly. The time between each plus sign (`+' ) in the escape code should not exceed the guard time. The plus signs in the escape code can be changed to another ASCII character by changing the value in register S2. COMMAND LINE SYNTAX The prefix AT (think "ATtention") must start each command line except A/ and be in all uppercase (AT) or all lowercase (at) characters. The modem examines the AT code to determine your computer's serial port rate, parity, word length, and number of stop bits, and then stores your current configuration in its memory. Multiple commands can appear on one command line. You can separate these with spaces to improve readability if you like (the modem ignores the spaces). Each command line (except A/) must end with a carriage return ([CR]_ASCII 13). If you don't provide a carriage return, the modem ignores the commands.A line feed character following the carriage return is optional and is ignored by the modem. The following are examples of valid command lines: AT DT 555-5055 [CR] ATH [CR] AT &F &C1 &D2 &W [CR] A/ COMMAND LINE BUFFER The modem places each command issued into a command buffer that holds up to 40 characters. The modem does not place the AT, carriage return, or line feed characters, so the buffer's 40 spaces only hold actual command characters. If a command line contains more than 40 command characters, the modem ignores the commands and displays the ERROR result code. RESULT CODES After the modem receives a command, it returns a result code. The most common result code is OK, which means the modem understood your command.Other result codes are listed in Appendix C. Result codes can be represented by English words or with numbers. Words are preceded and followed by carriage return and line feed characters. Numbers are followed by a carriage return. Refer to the V command in Appendix C for more information. ***************************************************************************** CHAPTER 3: USING MNP, V.42BIS, & FLOW CONTROL ***************************************************************************** Your modem features error correction and data compression protocols that allow you to transmit data error-free at rates faster than the actual line connection rate. What may be a mystery now becomes clear once you have an understanding of what the modem is actually doing. Pay careful attention to this chapter to make sure you are using your modem to its fullest potential. START WITH THE BASICS To understand this technology, you need to know these basic ideas: * Your modem supports V.42 (LAPM and MNP 2-4) error correction, and MNP 5 and V.42bis (BTLZ) data compression. * MNP 2, 3, and 4 are the MNP error correction protocols. MNP stands for "Microcom Networking Protocol (MNP)" after the company that developed these protocols. MNP 4 is often the highest level connection you can get on many of the commercial services like CompuServe. * MNP 5 is an MNP data compression protocol. It offers a compression rate of up to 2:1 ("throughput" to 19,200 (V.32) or 28,800 bps (V.32bis)). MNP 5 connections also use MNP error correction. * LAPM is an error correction protocol used in V.42. * BTLZ is the data compression protocol used in V.42bis. It offers compression of up to 4:1 (throughput to 38,400 (V.32) or 57,600 bps (V.32bis)). BTLZ connections require LAPM error correction. * V.42 is the CCITT error correction protocol. (CCITT is an international standards setting committee.) V.42 uses LAPM as the preferred protocol and MNP 4, 3, or 2 if LAPM is not available. MNP 10 is not part of V.42. * V.42bis adds BTLZ data compression to the V.42 protocol. MNP 5 is not part of V.42bis. * Your modem may also support MNP 10, for cellular communication, providing an extreme level of error correction on adverse connections. MNP 10 is optional feature #143, which is only available on select modem models. The I10 command tells which optional features your modem supports. * Both your modem and the remote modem must support the same data compression/error correction protocols. If the other modem does not support the same protocols that your modem supports, you can connect and communicate, but you will not be able to use all the protocols your modem supports. * "Remote Modem" is the modem your modem connects to. * "Throughput" is the effective transfer rate. In general, on a 9600 bps connection, data will transfer at a maximum of 9600 bps, meaning maximum throughput is 960 characters per second. But on a 9600 bps MNP 5 connection, where MNP 5 can compress the data to half its original size, throughput can be double that of the 9600 bps connection without MNP 5, or 19,200 bps. The .connection rate and actual transmission speed are still only 9600 bps. * "Connection Rate" is the rate at which your modem and the remote modem connect, such as 9600 bps or 14,400 bps. This rate is determined by the modems when they connect. Synonyms: Line Speed, Modem-to-Modem Speed, DCE Speed#. * "Computer Rate" is the rate at which your modem and computer communicate. You change this rate in your software. With your modem, this rate should usually be higher than the connection rate. Synonyms: Serial Port Speed, .Modem-to-Computer Speed, DTE Speed. HOW ERROR CORRECTION & DATA COMPRESSION WORK Error Correction For error correction, the modem breaks your transmission down into blocks of data (frames) and calculates a checksum (the sum of all data bytes in the block). The block and its checksum are then transmitted. The receiving modem then calculates a checksum on the received data block and compares it with the received checksum. If these numbers are different, the data block was not transmitted properly, and the modem resends the data. Error correction is useful for communications that occasionally experience a little telephone line noise or some other "glitch."However, error correction will not perform miracles on extremely noisy lines.If you have lots of errors, you may need to have your telephone circuits checked or change long distance carriers. Data Compression Data compression is accomplished by the sending modem analyzing the outgoing data for often repeated patterns of data (such as the letters "A" and "E" in English text). It then assigns a shorter data code that will transmit faster than the original data. The more often the same data codes occurs in the transmission, the better compression the modem can achieve. Certain file types like text files and graphics screens are very good candidates for optimal compression. Files that have already been compressed with a program like Stuffit, PKZIP, or ARC may only gain 10-15% additional compression with V.42bis and could even show a slight performance decrease with Microcom Networking Protocol (MNP). The compression rates of 2:1 for MNP 5 and 4:1 for V.42bis were determined as typical using a standard non- compressed test document. Additional information is provided later in this chapter. CONNECTION RATES How the Modem Determines Connection Speed & Protocol Your modem first tries to connect to the remote modem at the highest rate your modem supports (14,400 bps or 9600 bps). If the remote modem can't connect at your modem's highest rate, your modem then tries to connect at the next highest rate (12,000 bps or 4800 bps, depending on your modem.If that doesn't work,it continues trying the remaining speeds the modem supports, one at a time in descending order. (This process is called "fall back.") If error correction and data compression are enabled (they are when shipped), the modem next tries to "negotiate" error correction and data compression protocols with the other modem. With your modem the order in which the protocols are tried is error correction, then data compression, and then a connection with no error correction or data compression. The protocols that will be used are the most powerful protocols that both modems support. Because your modem supports so many rates and protocols, this process can take several seconds to complete. If it seems to take an extremely long time, you may be having line noise problems; refer to Chapter 8. After Connecting Once connected, your modem sends your computer a result code that tells it the connection rate (for example, CONNECT 9600). Depending on how your software handles the result code, you either see the result code on your screen, or you see your software's interpretation of it. If .nonsense characters appear on your screen after this, the computer and connection rates are different. With modems that don't support error correction or data compression, and with "Direct" connections (explained in the next section), if the computer and connection rates are different you must use your software to change your computer rate to match the connection rate. (Otherwise, you'll only see nonsense characters.) Some software automatically does this after looking at the CONNECT XXXX message. Once your computer rate and connection rate match, you can start communicating directly with the remote computer. On your modem, the computer rate and connection rate do not have to match because of "flow control" (described later in this chapter). This lets your computer talk to your modem at a higher speed (say 38,400 bps) than your modem is talking to the remote modem (say 9600 bps). This is useful because data rates vary when using data compression, but it causes problems with software that automatically adjusts the computer rate to match the connection rate. For example, let`s say you set your computer rate to 38,400 bps (in your software) and then make a 9600 bps connection. Your modem could normally handle this, but when your software sees the CONNECT 9600 message, it decides it has to change the computer rate down to 9600 bps to match it -_ disabling your ability to take advantage of the higher throughput of data compression. The modem has a way around this, however. In its default settings (&F1 or &F2),the modem returns a CONNECT XXXX message to the computer telling it the computer rate (DTE) and not the connection rate. In the previous example with the computer at 38,400 bps and the connection at 9600 bps, it will return CONNECT 38400 and your software will stay at 38,400 bps. For more information, refer to the Wn command description in Appendix B. CONNECTION TYPES The following commands tell your modem what type of connection you want it to try. Do not use them during an active connection. \N1 Direct Connection If you use \N1, the modem will act just like a regular modem that doesn't support error correction or data compression. Your computer rate and connection rate must match. \N Normal Connection If you use \N, the modem will still act just like a regular modem, except that you won't have to change your computer rate to match the connection rate, because you'll be using "flow control" (Flow control is explained later in this chapter.) \N2 & N4 Reliable Connection If you use \N2, the modem will try to make an MNP connection (MNP 5, 4, 3, or 2). If it can't, the modem will hang up. If you use \N4, the modem will try to make a V.42bis, V.42, or MNP connection, and if it can't, it will hang up. Reliable connections also feature flow control. \N3 AutoReliable Mode If you use \N3, the modem will try to make the best connection possible.If it can make a V.42bis connection, it will. If not, it will "fall back" through V.42 and MNP, trying each one until it is able to connect.(It will not attempt a V.42bis connection if you've issued the %M0 command, or an MNP 5 connection if you've issued the %C0 command.) The connection the modem actually makes can be Reliable or Normal. In most situations, you'll want to use \N3. Flow Control Normal and Reliable connections use a technique called "flow control"that lets your computer rate (computer-to-modem rate) be different than your connection rate. Flow control is useful with data compression because your throughput is higher than the connection rate and because the throughput changes depending on the compressibility of the data being sent. Flow control lets your modem and computer tell each other when they can accept more data for transmission and when to wait. This "handshaking" prevents data from being lost because the computer or modem was busy. Your modem supports both "hardware" (RTS/CTS) and "software" (XON/XOFF) flow control. Hardware flow control (also called hardware handshaking) uses two of the modem's RS-232 lines for signaling. Software flow control uses special XON and XOFF characters to communicate between your computer and the modem. Hardware flow control is the preferable (and default) method because of its speed and reliability. To use hardware handshaking flow control, you must have: * Hardware handshaking cable (if your modem is external) such as the one that may have been provided with the modem. * Hardware (RTS/CTS) flow control enabled in your telecom software. If your modem came with telecom software, the software should have flow control enabled. * Flow control enabled by the &K3 command (RTS/CTS hardware flow control).&K3 is the factory default with &F1 and &F2. * DTR disabled (&D0) if you are using a Macintosh. &D0 is the factory default with &F1 (Mac). THE CONFIGURATIONS MOST PEOPLE NEED Simply issue &F1 (if you have a Macintosh) or &F2 (if you have any other type of computer). Then issue &W to store the configuration so it loads automatically when you turn on the modem. This tells your modem to use Auto Reliable mode, Hardware handshaking, and CONNECT XXXX messages that reflect the computer's rate. Chapter 7 provides more information. USING XMODEM, YMODEM, OR PRE-COMPRESSED FILES MNP 5 Data Compression We recommend disabling MNP 5 data compression (%C) when using an MNP Reliable connection and transferring files that are already compressed by compression software such as ARC, .ZIP, or StuffIt. When files compressed by these programs are transferred using MNP 5, the files sometimes actually take longer to transfer than files transferred using a Reliable connection without data compression. V.42bis Data Compression V.42bis is more sophisticated. When it recognizes that there is no benefit to compressing software-compressed data further,it does not attempt to use V.42bis compression. To receive this and other benefits, use V.42bis rather than MNP 5 whenever possible. Error Correction Unlike data compression, it is usually advantageous to use MNP 2-4 or LAPM error correction for any file transfer, regardless of compression or software- based error correction protocols such as Xmodem, Ymodem, etc. The error correction protocol strips start and stop bits from each character (improving throughput) and performs error correction on smaller chunks of data than do software-based error correction protocols (so if an error does occur, less data has to be retransmitted, taking less time) ***************************************************************************** CHAPTER 4: DIALING ***************************************************************************** Most of the time you'll use your telecommunications software to dial numbers, and you'll be able to mostly ignore this chapter. But at some point you may need to tell your software something it does not inherently know, or you may need to set your modem in some way that your software can't do for you. This chapter tells you what you need to know in situations like these. Refer to your software manual for instructions on using your software to dial numbers and answer calls. USING THE DIAL COMMAND Your modem dials phone numbers when you give it the dial command (D) and a phone number, either alone or with dial modifiers. The phone number must be an ASCII string containing the characters 0 through 9 (for pulse dial lines) or those numbers and A, B, C, D, #, and * (for touch- tone dial lines). The number cannot exceed the size of the command buffer (40 characters excluding the AT prefix, spaces, the carriage return control character, and the line feed control character). The modem uses the dial command modifiers (listed below) in the order it encounters them on the command line, from left to right. L dial last string dialed P pulse dial R reverse mode from originate to answer mode (R must be last character in the command line) Sx dial number stored in memory location x (x=0, 1, 2, or 3) T touch-tone dial W wait for dial tone before processing the next character in the dial string (useful for PBX phone systems) @ wait for quiet answer , pause before processing the next character in dial string ! hook flash (go on-hook for 700 ms.) ^ turn on calling tone if originating call (enabled on a call-by-call basis only) ; return to command state after dialing (must be last character in the command line) To aid readability, spaces, hyphens, and parentheses can be added to the dial command line without affecting its function. In the following example, your modem goes off-hook, waits for a dial tone, and then touch-tone dials the number 1 (405) 555-9624. AT DT 1 (405) 555-9624 [CR] If your modem does not receive a valid carrier from the remote modem within 30 seconds (the default value of register S7), your modem hangs up and sends the NO CARRIER result code. If the modem does receive a valid carrier within the time allowed, it will send a CONNECT XXXX message indicating the connection rate. DIALING FROM A TELEPHONE You can also dial a number yourself on a telephone and give the modem a command that tells it you want to connect to another modem. The modem offers two ways to do this. The first method lets you call a remote modem that is set to auto answer.It is to be used in situations where you will not talk to a person before the modems connect. When you have a choice, we recommend simply using the modem to dial the number, instead of using this method. If you need to use this method, follow these steps: 1. Type the following but do not press the .carriage return: AT X3 D 2. Dial the number yourself on the telephone. 3. When you hear a carrier, press the carriage return [CR].Your modem will try to connect with the remote modem. The second method lets you talk to someone on the phone and then connect modems without hanging up. To do this, follow these steps: 1. Talk to each other using .telephones plugged into the PHONE jacks on the backs of your modems. 2. When you're done talking and you're ready to start using the modems, DO NOT hang up your telephone receivers. 3. One of you: Type ATA [CR]. The other one of you: Type AT X3 D [CR]. You'll both hear a high- pitched squeal from your modem speakers (if they're turned on). Then you should both see a .CONNECT result code appear on your screens. 4. Hang up your phone receiver, and you are online. When you're done, hang up the modems through your software or by issuing the escape code (+++), followed by the AT H command. STORING A TELEPHONE NUMBER You can store up to 4 frequently called phone numbers in your modem's memory by using the &Zx=n command, where x is the modem's memory location and n is the number to store (which cannot exceed 36 characters). The value in x can be 0, 1, 2, or 3, with x=0 the default. For example, this saves tone-dialed number T555-9624 in location 1: AT &Z1=T555-9624 [CR] DIALING A STORED NUMBER To dial a stored number, use D with the Sx modifier. This command dials the number stored in memory location x. For example, the following command dials the number in memory location 1: AT DS1 [CR] AUTOMATIC PULSE DIALING IF TELEPHONE SYSTEM DOES NOT SUPPORT TOUCH TONES If your local telephone system does not support touch-tone dialing, the way your modem acts depends on how it is configured. If your dial string includes the P dial command modifier OR you have previously issued the P command, the modem will pulse dial. If your dial string includes the T dial command modifier OR you have previously issued the T command, the modem will tone dial. If your dial string does not include a P or T dial command modifier AND you have previously issued the T command, the modem will do the following: 1. Listen for dial tone. (Note that changing the X command from its default can affect this step.) 2. Tone dial the first digit in the dial string. 3. Wait up to 3 seconds for the dial tone to end. 4. If the dial tone ends, the modem continues dialing. If the dial tone does not end, the modem knows your phone system can only handle pulse dialing (because the phone system did not process the tone-dialed first digit). So it switches to pulse mode, pulse dials the first digit, and then pulse dials the rest of the number. Note that this feature can cause problems with PBX systems -_ for example, systems where a 9 is dialed to get a dial tone outside a company's in-house phone system. Such systems deliver a second dial tone after receiving the first digit. DISABLING CALL WAITING If you have "call waiting," we recommend that you disable it before using your modem. If you don't disable it and a call comes in while you are online, you will either lose data or be disconnected. Please refer to your local telephone book or phone company for directions on how to do this. In many locations, you can disable call waiting by placing *71 or *70 in the dial string, either just before or after the number you are dialing. For example, you might use: AT DT *71 555-0000 [CR] Call waiting usually resumes immediately after you hang up, so you will have to do this on each call. If your software has a built-in dialing prefix (or macro) you can probably include this code so it is used on every call ***************************************************************************** CHAPTER 5: ANSWERING ***************************************************************************** Your modem can answer telephone calls and (with help from your telecom munications or fax software) manage those calls appropriately. Under certain conditions, the modem can also tell you who is calling, before the call is answered. Your fax and telecom software should be able to handle most answering tasks. However, because some of the modem's capabilities are relatively new, a thorough understanding of the answering process will help you set up your software and modem for optimal performance. This chapter is designed to give you that understanding as well as to explain the basic techniques for answering incoming telephone calls. (For more information on your software, refer to your software manuals.) ANSWERING CALLS Your modem provides three ways to answer calls: * You issue the A command when you detect an incoming call. This makes the modem answer the call immediately. The modem will go online when it detects a carrier. * You talk on a phone and then connect modems. This is described in Chapter 4, "Dialing From a Telephone." * You set your modem to "auto answer." In this case, your modem automatically answers all incoming calls. The rest of this section explains how to use auto answer. Your modem answers calls automatically (auto answer) if you set register S0 to a value from 1 to 255. This value is the number of rings the modem will wait before it answers the call. The following example sets the modem to answer calls after the second ring: AT S0=2 [CR] If you set the modem to auto answer and your modem shares a line with a telephone, the modem may answer calls before you can intercept it. Be careful with auto answer unless you have a dedicated modem phone line. By default, auto answer is disabled. On some modem models, if you set the modem to auto answer, the modem displays the AA message unless the modem detects a ring signal. Then when the modem does detect a ring, the RI message is displayed for 2 seconds. If you plan to connect your modem directly to a mainframe or minicomputer where it will be .dedicated to auto answer operation, you might need to change the modem's configuration from its defaults. Because every situation is different, it's hard to say what you'll need to change. First try the Q1 command. If Q1 doesn't solve the problem, also try .&D, and if there's still a problem, also try &C. Please call Technical Support if you need assistance. If you plan to use your modem to run a Bulletin Board System (BBS), the BBS software should automatically configure it for auto answer operation. If you think that you need to change it, refer to your BBS software manual or contact the BBS software publisher for details on how your modem should be set. IDENTIFYING THE SOURCE OF AN INCOMING CALL (CALLER ID) Caller ID is a way for you to find out who is calling before you answer a telephone call. In between the first and the second ring of an incoming call, the phone company sends information such as: * the date and time of the call * the phone number from which the call originated * possibly a name associated with that phone number The information displayed will vary depending on your phone company and your software. Caller ID (optional feature #141) is not available on all modem models.The I10 command reports which optional features your modem supports. Potential Applications Caller ID can be used by many computer applications for improved security, efficiency, and convenience. Here are a few of the potential applications: * Bulletin Board Systems (BBSs). A BBS can positively identify callers without the normal tedious logon sequences, and prevent unauthorized entry due to lost or stolen accounts and passwords. * Screening Calls. Your computer can display the number and possibly name of who is calling, so you can decide if you want to answer or not. * Professional billing. Your computer can match incoming calls to your client list and automatically create a charge to the client's account for your phone time. * Database Lookup. Your customer's record or account can be displayed on your computer screen before you answer the call. Your ability to take advantage of these applications (and others) depends on your software. Can You Use Caller ID? To use the modem's Caller ID feature: * Your local telephone company must provide Caller ID, and it must be enabled for your telephone line. At present, Caller ID is only available in some areas of the country. If your phone company does not offer Caller ID, you cannot use your modem's Caller ID feature. To find out if Caller ID is available in your area, contact your local telephone company. * You must have software that allows you to use Caller ID. The "Software Options" section explains software requirements. * Your modem's Caller ID feature must be turned on. The "Caller ID AT Commands" section in this chapter provides more information. Software Options The degree to which you can take advantage of Caller ID depends on your software: * Incoming Data Calls At present, most people use telecommunications software to take advantage of Caller ID. If configured to do so, when the modem receives an incoming call, it displays the call information in the telecom software's terminal mode screen. After reading the information displayed in your telecom software, you can either let your modem answer the call or you can answer the call yourself using a telephone handset. The "How to Use Caller ID with Telecommunications Software" section in this chapter provides more information. * Incoming Fax Calls To use the Caller ID feature with incoming fax calls,your fax software must support Caller ID. If your fax software does, refer to your fax software manual to learn how to use this feature. * Additional Applications Many widely used BBS programs now support Caller ID. Caller ID AT Commands The following AT commands enable and disable Caller ID: #CID=0 Disables Caller ID. #CID=1 Enables Caller ID in formatted format. #CID=2 Enables Caller ID in unformatted format (ASCII printable hex numbers). How to use Caller ID with Telecommunications Software As with any AT data commands, you can issue the Caller ID commands from your telecommunications software terminal mode, or include them in your telecom software's initialization string. Other software that supports Caller ID will probably issue these commands automatically. The following steps explain how to use telecommunications software to take advantage of Caller ID. 1. Read the "Can You Use Caller ID?" section earlier in this chapter. 2. Start your telecommunications software and make sure it is in terminal mode. 3. Configure your modem for Caller ID by typing the following commands in your software's terminal mode. As an alternative, you can include the commands in your telecom software's init string. [CR] represents a carriage return. a. Enable the modem's Caller ID feature. AT #CID=1 [CR] b. Make sure no other devices (such as your modem, answering machine, or fax machine) answer before the second ring. For example, you can set your modem to answer on the third or later ring, as shown below.(The phone company sends the Caller ID information between the first and second ring of an incoming call.) AT S0=3 [CR] c. If you want to skip step 3 in the future, issue the following command to save the above commands in your modem's nonvolatile memory. AT &W0 [CR] 4. Now the modem is ready to receive an incoming call. When a call comes in, the telecom software's terminal mode screen will reflect the modem' activity. It will look something like this: RING DATE = 0321 TIME = 1405 NMBR = 5039672400 NAME = ANYCOMPANY RING Here is an explanation of this display: * The first RING result code appears when the modem receives the first ring signal (equivalent to a telephone ringing once). * The next four lines represent the Caller ID information, which the phone company sends in between the first and second ring of an incoming call. * The actual information displayed will vary depending on your phone company. For example, the date and time may be displayed in different locations, and the "name" might not be included. Also, some extraneous characters might be included. For example, several customers have told us that in parts of Canada, in place of single spaces the number "30" is displayed. * The second RING result code represents the second ring signal the modem receives. 5. If you recognize the phone number or name displayed in step 4, you may be able to determine if the call is voice or data. 6. Now do one of the following: * If the call is from a person (a "voice call"),pick up the telephone handset and answer the call yourself. * If the call is from another modem (a "data call"), let your modem answer the call automatically. If the modem answers the call, you will then see a CONNECT result code (or whatever message your software displays upon receiving a CONNECT result code). DISTINGUISHING BETWEEN INCOMING VOICE, FAX, AND DATA CALLS (SILENT ANSWER AND ADAPTIVE ANSWER) Your modem can determine if an incoming call is fax or data, or if an incoming call is fax or voice (if your modem supports Silent Answer). At this time, it cannot distinguish between incoming fax, voice, and data calls. When a call comes in, your modem knows if the call is a fax because it detects fax tones from the sending fax machine. But if the modem does not detect fax tones, it can only do one of the following: * assume the call is a voice call (Silent Answer) and allow you or your answering machine to take the call * assume the call is a data call (Adaptive Answer), send a data carrier, and wait for the remote modem to try to connect If the remote modem does not detect fax tones, it knows the incoming call is either voice or data. But there is no way to determine which it is (voice or data). To understand why, think for a minute about when you make a data call to a remote modem. Your modem dials and then waits for a "data carrier" to be sent from the remote modem (the answering modem). Data carriers are generated only by an answering modem. So when your modem answers an incoming call and tries to determine whether it is voice or data, it "hears" nothing it recognizes _- since the modem originating a data call does not generate a carrier. So it must assume either that the call is a data call (and send a data carrier) or a voice call (and remain silent). By choosing either Silent Answer or Adaptive Answer, you tell the modem whether to treat non-fax calls as voice calls or data calls. It is possible to switch back and forth between Silent Answer and Adaptive Answer, but they cannot both function at the same time. SILENT ANSWER Silent Answer (optional feature #141) is not available on all modem models. The I10 command reports which optional features your modem supports. What is Silent Answer? With Silent Answer, when a call comes in, the modem lets another device _- an answering machine, or a person using a telephone -_ answer the incoming call. As soon as an answering machine or person answers the call, the modem silently "listens" to the sound coming over the line. Then: * If the modem detects fax "CNG" tones, it attempts a fax connection. * If the modem does not detect fax tones, it does nothing, allowing you or your answering machine to continue handling the call. The following is what happens when Silent Answer is enabled and the modem receives an incoming call. 1. An incoming call causes a ring signal to come across the telephone line. 2. The answering machine (or a person) answers the call. This assumes your answering machine is set to answer an incoming call on fewer rings than the modem. (For example, the answering machine is set to answer on the third ring, and the modem is set to answer on the fourth ring.)It is preferable for the answering machine to answer on the third ring and the modem to answer on the fourth (or fifth if you are having difficulty receiving) ring. 3. If the modem detects fax "CNG" tones, the modem, fax software, and computer handle the fax call. 4. If the incoming call is NOT a fax call (incoming call is a voice or data call): a. Silent Answer does not detect fax "CNG" tones,so it knows the call is not a fax call. b. Silent Answer does not detect data carrier tones, even if the call is a data call. This is because when data connections are attempted, the data carrier tones are generated by the answering modem, not the originating modem. c. Because Silent Answer does not detect data carrier tones, Silent Answer assumes the call is not a data call. d. Because Silent Answer thinks the call is neither fax nor data (incoming call is a voice call), the modem does not go off hook. e. Answering machine handles the call. The implementation of Silent Answer depends on your software. Silent Answer is a proprietary feature and is not available on all varieties of modems. Do You Need to Use Silent Answer? The primary benefit of Silent Answer is that it lets your modem distinguish between incoming fax and voice calls when both the faxmodem and an answering machine (or telephone) are connected to the same telephone line. This eliminates the need for dedicated fax and voice lines. Can You Use Silent Answer? To use Silent Answer: * Your modem must support Silent Answer * Your fax software must support Silent Answer. * Your modem and answering machine must NOT be "daisy-chained." In other words, do not plug the answering machine into the back of the modem, and do not plug the modem into the back of the answering machine Instead: - Plug the answering machine and modem into different wall jacks (e.g.,jacks in different rooms). - If both devices are to be connected to one telephone wall jack, use a "Y jack" at the outlet, and plug each device into the Y jack. * Your answering machine tape must be "blank" for the first 3 seconds before the message. This allows the fax CNG tones to get through. * If you have an older answering machine that does NOT automatically turn itself off when it detects that a person or the modem has answered the call, you need a $7.95 adapter from Radio Shack, part #43-107. This adapter disconnects the answering machine from the phone line when the call is answered. It goes between the answering machine and the wall jack. Make sure the modem is not connected after the adapter. ADAPTIVE ANSWER What is Adaptive Answer? Adaptive Answer lets your modem determine if an incoming call is fax or data and handle the call appropriately. With Adaptive Answer ENABLED, and Silent Answer disabled, the following is what happens when the modem receives an incoming call. 1. An incoming call causes a ring signal to come across the telephone line. 2. The modem answers the call. 3. If the modem detects fax "CNG" tones, the modem, fax software, and computer handle the fax call. 4. If the modem does not detect fax tones, it assumes the call is a data call. It sends a data carrier and waits for the remote modem to try to connect. 5. If a remote modem responds, the modems try to connect. 6. If no remote modem responds, the modem hangs up. The implementation of Adaptive Answer depends on your software. If Silent Answer and Adaptive Answer are both ENABLED, Silent Answer takes precedence. Can You Use Adaptive Answer? To use Adaptive Answer, your fax software must support it.Please consult your fax software manual booklet to determine if your software supports Adaptive Answer. If your fax software does not support Adaptive Answer, please refer to the section below, "Software That Does Not Support Silent Answer/Adaptive Answer SOFTWARE ISSUES Software That Supports Silent Answer/Adaptive Answer If your fax software DOES support Silent Answer or Adaptive Answer, please refer to the fax software manuals for specific instructions on using it. Software That Does Not Support Silent Answer/Adaptive Answer If your fax software does not support Silent Answer or Adaptive Answer, please contact the software company to obtain a version of your software that does support these features. Software vendors are being encouraged to add support for Silent Answer and Adaptive Answer to their software. If your fax software does not support Silent Answer or Adaptive Answer, you might be able to modify your fax software initialization string, or in some other way modify your fax software, to use these features. ***************************************************************************** CHAPTER 6: CONNECTING ***************************************************************************** A connection begins after one modem answers a call from another modem,and ends when either modem disconnects. Because of "negotiation," the process of making a connection might take several seconds after dialing. Chapter 3 explains negotiation. BELL & CCITT PROTOCOLS Your modem supports the following communications protocols: Bell 103, Bell 212A, .CCITT V.21, CCITT V.22, CCITT V.22bis, CCITT V.32, and CCITT V.32bis (optional feature #140). These protocols define the basic communications link between the two modems _- that is, the frequency of the tones they use and how they modulate the data. These protocols are completely separate from the error correction and data compression protocols. The exact protocols that you will use are determined by the type of modem you are connecting to. For 300 bps and 1200 bps connections, there is one set of protocols used in the U.S. and Canada and another used in most of the rest of the world. The U.S. protocols are Bell 103 (300 bps) and Bell 212A (1200 bps) -_ named after the AT&T Bell Labs that developed them. For Europe, and much of the rest of the world, the protocols adopted by the CCITT (an international standards committee) are used: V.21 (300 bps), and V.22 (1200 bps). You will probably only use one set of these protocols, unless you make international calls. At 2400 bps and faster connections, CCITT protocols are used everywhere: V.22bis (2400 bps), V.32 (4800/9600 bps), and V.32bis (7200/9600/12,000/14,400 bps) CONNECTION RATES Chapter 3 explains how error correction and data compression affect connection rates. CONNECTION TYPES The following connections are possible between two modems like yours.Chapter 3 provides more information: ORIGINATING MODEM CALLS AT: --------------------------------------------------------- | NORMAL \N | DIRECT \N | RELIABLE | AUTO- | RELIABLE | | | \N2 | RELIABLE | \N4 | | | | \N3 | ------------|-----------|-----------|----------|-----------|--------- ERING | NORMAL \N | Normal | Direct | hangs up | Normal | Hangs up MODEM SET | | | or Normal | | | TO: |-----------|-----------|-----------|----------|-----------|--------- | DIRECT \N | Normal | Direct | hangs up | Normal | hangs up | | or Direct | | | or Direct | |-----------|-----------|-----------|----------|-----------|--------- | RELIABLE | hangs up | hangs up | MNP | MNP | MNP | \N2 | | | | | |-----------|-----------|-----------|----------|-----------|--------- | AUTO-\N3 | Normal | Direct | MNP | LAPM or | LAPM or | RELIABLE | | or Normal | | MNP | MNP |-----------|-----------|-----------|----------|-----------|--------- | RELIABLE | hangs up | hangs up | MNP | LAPM or | LAPM or | \N4 | | | | MNP | MNP --------------------------------------------------------------------- All Normal and Reliable connections also take advantage of flow control, which allows your computer and modem rates to be different. With Direct connections, these rates must be the same. You can only use data compression if you have made an error correcting (MNP or LAPM) connection with another modem that supports data compression. MNP 5 is only used with MNP error correction, and BTLZ is only used with LAPM error correction. If a data compression connection cannot be made, or if %C0 or %M0 have been used to disable data compression, only error correction will be attempted. ***************************************************************************** CHAPTER 7: CREATING CUSTOM MODEM CONFIGURATIONS ***************************************************************************** DO YOU NEED TO CONFIGURE YOUR MODEM? Before your modem left the factory, it was set up to act a certain way; for example, it returns full-word result codes and waits for a dial tone before dialing. These settings will work for most situations, but in some circumstances, you may need to change your modem's default configuration _- like if you want to change the speaker volume setting. This chapter tells how to do that. FACTORY DEFAULT, ACTIVE, & STORED CONFIGURATIONS There are three types of modem configurations: * The "factory default configuration" is stored in the modem's permanent memory (called firmware ROM). There are 3 different factory configurations, depending on what kind of computer you are using and if you need error correction and data compression. * The "active configuration" is the configuration you're using when you have your modem turned on. It is stored in the modem's temporary memory (called temporary RAM). * If you save the active configuration, it becomes a "stored configuration" that resides in the modem's nonvolatile RAM ("novram"). Whenever you turn on your modem, it loads a stored configuration from nonvolatile memory into the active configuration area. If you don't save your active configuration, it will be lost when you turn the modem off. CREATING A CUSTOM CONFIGURATION You can create a custom configuration by changing the settings that comprise the active configuration. The modem's AT commands let you change most of these settings by issuing single commands. Occasionally, you may need to change a setting by issuing the Sr=n command, which changes low-level S registers. AT Commands Used When Creating a Custom Configuration You can use a number of different AT commands to change settings, including the following commands, which are particularly useful. Be sure you understand Chapter 2 before using AT commands. Appendix B explains AT commands in detail * &F0, &F,1 and &F2, which reset the active configuration to preset factory default configurations. * &V, or \S (optional feature #146), which display configurations.The I10 command reports which optional features your modem supports. * &Wn (where n is profile 0 or 1), which saves your active configuration in the modem's nonvolatile RAM. * Zn (where n is profile 0 or 1), which resets the modem and loads the stored configuration from profile 0 or 1. * &Y1, which causes the stored configuration from profile 1 to be loaded into the active configuration area when you turn on or reset your modem.If you do not issue &Y1, the configuration from profile 0 is loaded instead. AT Commands for Changing S Registers Directly Sr? displays the value in register r. For example, ATS0? reads S register 0 and displays three digits -_ 005 if the value is 5. Appendix D describes your modem's S registers. Sr=n sets the value in S register r to n. The n must be a decimal integer from 0 to 255. For example, the command ATS0=4 [CR] sets register S0 to 4, which causes the modem to automatically answer all incoming calls after the fourth ring. The modem replies with OK. Note: If you have a choice, it is usually easier to use the AT commands to change S registers indirectly, instead of using Sr=n. &F, &F1, &F2: THE FACTORY CONFIGURATIONS The following commands load the factory default configurations: &F Load basic 9600 or 14,400 bps configuration, with error correction and data compression disabled. This command includes these settings: \N1 &K0 &Q0 &D2. Use this configuration if your telecom software or modem cable does not support hardware handshaking (regardless of your computer type). In this case, you will not be able to use data compression or error correction. &F1 Load Macintosh error correction/data compression configuration.This command includes these settings: \N3 &K3 &Q5 &D0. This is the configuration needed by most Macintosh computers, except those using either telecom software that does not support hardware handshaking or a modem cable that does not support hardware handshaking. &F2 Load IBM (and others) error correction/data compression configuration This command includes these settings: \N3 &K3 &Q5 &D2. This is the configuration needed by most computers, except Macintosh computers and any computer using either software or cable that does not support hardware handshaking. The settings included with &F1 and &F2 do the following: \N3 AutoReliable connection. Makes the fastest possible connection and uses the best possible error correction and data compression &K3 RTS/CTS hardware flow control. Allows you to use data compression and error correction. &Q5 Asynchronous error correction mode. &D0, &D2 Selects correct DTR settings so hardware handshaking flow control will work.