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diff --git a/doc/kppp/hayes.docbook b/doc/kppp/hayes.docbook new file mode 100644 index 00000000..a8f6db7f --- /dev/null +++ b/doc/kppp/hayes.docbook @@ -0,0 +1,927 @@ +<appendix id="appendix-hayes-commands"> +<title>The Hayes Modem Command Set</title> + +<para>Here is a description of the Hayes Command Set. Most modems follow this +command set to large extent. If you lost your modem manual or never had one in +the first place, this reference might come in handy. I for instance finally found +out how to turn my modems speaker off: <command>ATM0</command> -- Finally: +Silence!</para> + +<para>The modem initialization string consists of a series of commands. It +prepares the modem for communications, setting such features as dialing mode, +waits, detection of the busy signal and many other settings. Newer modem +communications programs reset the initializations string for you according to +which menu options you select, which features you enable, &etc;.</para> + +<para>For many years Hayes modems have been the standard. As the field of modem +manufactures has grown, most have adhered at least loosely to the Hayes +standard. The following is a partial list of the Hayes command set. (called the +<quote>AT</quote> commands). The Hayes Command Set can be divided into four +groups:</para> + +<variablelist> +<varlistentry> +<term>Basic Command Set</term> +<listitem><para>A capital character followed by a digit. For example, +<command>M1</command>.</para></listitem> +</varlistentry> +<varlistentry> +<term>Extended Command Set</term> +<listitem><para>An <quote>&</quote> (ampersand) and a capital character +followed by a digit. This is an extension of the basic command set. For example, +<command>&M1</command>. Note that <command>M1</command> is different from +<command>&M1</command>.</para></listitem> +</varlistentry> +<varlistentry> +<term>Proprietary Command Set</term> +<listitem><para>Usually started by either a backslash (<quote>\</quote>), or a +percent sign (<quote>%</quote>), these commands vary widely among modem +manufacturers. For that reason, only a few of these commands are listed +below.</para></listitem> +</varlistentry> +<varlistentry> +<term>Register Commands</term> +<listitem><para><command>S<replaceable>r</replaceable>=<replaceable>n</replaceable></command> +where <replaceable>r</replaceable> is the number of the register to be changed, +and <replaceable>n</replaceable> is the new value that is +assigned.</para> + +<para>A <quote>register</quote> is computerese for a specific physical location +in memory. Modems have small amounts of memory onboard. This fourth set of +commands is used to enter values in a particular register (memory location). The +register will be storing a particular <quote>variable</quote> (alpha-numeric +information) which is utilized by the modem and communication software. For +example, <command>S7=60</command> instructs your computer to <quote>Set register +#7 to the value 60</quote>.</para></listitem> +</varlistentry> +</variablelist> + +<note><para>Although most commands are defined by a letter-number combination +(<command>L0</command>, <command>L1</command> &etc;), the user of a zero is +optional. In this example, <command>L0</command> is the same as a plain +<command>L</command>. Keep this in mind when reading the table +below!</para></note> + +<para>Here are some of the most important characters that may appear in the +modem initialization string. These characters normally should not be +changed.</para> + +<variablelist> +<varlistentry> +<term><command>AT</command></term> +<listitem><para>Tells the modem that modem commands follow. This must begin +each line of commands.</para></listitem> +</varlistentry> +<varlistentry> +<term><command>Z</command></term> +<listitem><para>Resets the modem to it's default state</para></listitem> +</varlistentry> +<varlistentry> +<term><command>,</command> (a comma)</term> +<listitem><para>makes your software pause for a second. You can use more than +one <command>,</command> in a row. For example, <command>,,,,</command> tells +the software to pause four seconds. (The duration of the pause is governed by +the setting of register <varname>S8</varname>.</para></listitem> +</varlistentry> +<varlistentry> +<term><command>^M</command></term> +<listitem><para>Sends the terminating Carriage Return character to the modem. +This is a control code that most communication software translates as +<quote>Carriage Return</quote></para></listitem></varlistentry> +</variablelist> + +<sect1 id="hayes-basic-commands"> +<title>The Basic Hayes Command Set</title> + +<para>In alphabetical order:</para> + + <table> + <title>Basic Hayes Command Set</title> + <tgroup cols="3"> + <thead> + <row> + <entry>Command</entry> + <entry>Description</entry> + <entry>Comments</entry> + </row> + </thead> + <tbody> + <row> + <entry><command>A0</command> or <command>A</command></entry> + <entry>Answer incoming call</entry> + <entry></entry> + </row> + <row> + <entry><command>A/</command></entry> + <entry>Repeat last command</entry> + <entry>Don't preface with <command>AT</command>. Enter usually + aborts.</entry> + </row> + <row> + <entry><command>B0</command> or <command>B</command></entry> + <entry>Call negotiation</entry> + <entry>V32 Mode/CCITT Answer Seq.</entry> + </row> + <row> + <entry><command>B1</command></entry> + <entry>Call negotiation</entry> + <entry>Bell 212A Answer Seq.</entry> + </row> + <row> + <entry><command>B2</command></entry> + <entry>Call negotiation</entry> + <entry>Verbose/Quiet On Answer</entry> + </row> + <row> + <entry><command>D</command></entry> + <entry>Dial</entry> + <entry><para>Dial the following number and then handshake in originate + mode.</para><variablelist> + <varlistentry> + <term><command>P</command></term> + <listitem><para>Pulse Dial</para></listitem> + </varlistentry> + <varlistentry> + <term><command>T</command></term> + <listitem><para>Touch Tone Dial</para></listitem> + </varlistentry> + <varlistentry> + <term><command>W</command></term> + <listitem><para>Wait for the second dial tone</para></listitem> + </varlistentry> + <varlistentry> + <term><command>,</command></term> + <listitem><para>Pause for the time specified in register + <varname>S8</varname> (usually 2 seconds</para></listitem> + </varlistentry> + <varlistentry> + <term><command>;</command></term> + <listitem><para>Remain in command mode after dialing.</para></listitem> + </varlistentry> + <varlistentry> + <term><command>!</command></term> + <listitem><para>Flash switch-hook (Hang up for a half second, as in + transferring a call.</para></listitem> + </varlistentry> + <varlistentry> + <term><command>L</command></term> + <listitem><para>Dial last number</para></listitem> + </varlistentry> + </variablelist></entry> + </row> + <row> + <entry><command>E0</command> or <command>E</command></entry> + <entry>No Echo</entry> + <entry>Will not echo commands to the computer</entry> + </row> + <row> + <entry><command>E1</command></entry> + <entry>Echo</entry> + <entry>Will echo commands to the computer (so one can see what one + types)</entry> + </row> + <row> + <entry><command>H0</command></entry> + <entry>Hook Status</entry> + <entry>On hook - Hang up</entry> + </row> + <row> + <entry><command>H1</command></entry> + <entry>Hook status</entry> + <entry>Off hook - phone picked up</entry> + </row> + <row> + <entry><command>I0</command> or <command>I</command></entry> + <entry>Inquiry, Information, or Interrogation</entry> + <entry>This command is very model specific. <command>I0</command> + usually returns a number or code, while higher numbers often provide much + more useful information.</entry> + </row> + <row> + <entry><command>L0</command> or <command>L</command></entry> + <entry>Speaker Loudness. Modems with volume control knobs will not have + these options.</entry> + <entry>Off or low volume</entry> + </row> + <row> + <entry><command>L1</command></entry> + <entry></entry> + <entry>Low Volume</entry> + </row> + <row> + <entry><command>L2</command></entry> + <entry></entry> + <entry>Medium Volume</entry> + </row> + <row> + <entry><command>L3</command></entry> + <entry></entry> + <entry>Loud or High Volume</entry> + </row> + <row> + <entry><command>M0</command> or <command>M</command></entry> + <entry>Speaker off</entry> + <entry><command>M3</command> is also common, but different on many + brands</entry> + </row> + <row> + <entry><command>M1</command></entry> + <entry></entry> + <entry>Speaker on until remote carrier detected (&ie; until the other + modem is heard)</entry> + </row> + <row> + <entry><command>M2</command></entry> + <entry></entry> + <entry>Speaker is always on (data sounds are heard after CONNECT)</entry> + </row> + <row> + <entry><command>N0</command> or <command>N</command></entry> + <entry>Handshake Speed</entry> + <entry>Handshake only at speed in <link linkend="hayes-s37"><varname>S37</varname></link></entry> + </row> + <row> + <entry><command>N1</command></entry> + <entry></entry> + <entry>Handshake at highest speed larger than <link linkend="hayes-s37"><varname>S37</varname></link></entry> + </row> + <row> + <entry><command>O0</command> or <command>O</command></entry> + <entry>Return Online</entry> + <entry>See also <link linkend="hayes-basic-x1"><command>X1</command></link> as dial tone + detection may be active.</entry> + </row> + <row> + <entry><command>O1</command></entry> + <entry></entry> + <entry>Return Online after an equalizer retrain sequence</entry> + </row> + <row> + <entry><command>Q0</command> or <command>Q1</command></entry> + <entry>Quiet Mode</entry> + <entry>Off - Displays result codes, user sees command responses (⪚ + <computeroutput>OK</computeroutput>)</entry> + </row> + <row> + <entry><command>Q1</command></entry> + <entry>Quiet Mode</entry> + <entry>On - Result codes are suppressed, user does not see + responses.</entry> + </row> + <row> + <entry><command>S<replaceable>n</replaceable>?</command></entry> + <entry></entry> + <entry>Query the contents of S-register + <replaceable>n</replaceable></entry> + </row> + <row> + <entry><command>S<replaceable>n</replaceable>=<replaceable>r</replaceable></command></entry> + <entry>Store</entry> + <entry>Store the value of <replaceable>r</replaceable> in S-register + <replaceable>n</replaceable></entry> + </row> + <row> + <entry><command>V0</command> or <command>V</command></entry> + <entry>Verbose</entry> + <entry>Numeric result codes</entry> + </row> + <row> + <entry><command>V1</command></entry> + <entry></entry> + <entry>English result codes (⪚ + <computeroutput>CONNECT</computeroutput>, + <computeroutput>BUSY</computeroutput>, <computeroutput>NO + CARRIER</computeroutput> &etc;)</entry> + </row> + <row> + <entry><command>X0</command> or <command>X</command></entry> + <entry>Smartmodem</entry> + <entry>Hayes Smartmodem 300 compatible result codes</entry> + </row> + <row> + <entry><anchor id="hayes-basic-x1"/><command>X1</command></entry> + <entry></entry> + <entry>Usually adds connection speed to basic result codes (⪚ + <computeroutput>CONNECT 1200</computeroutput></entry> + </row> + <row> + <entry><command>X2</command></entry> + <entry></entry> + <entry>Usually adds dial tone detection (preventing blind dial, and + sometimes preventing <command>AT0</command>)</entry> + </row> + <row> + <entry><command>X3</command></entry> + <entry></entry> + <entry>Usually adds busy signal detection</entry> + </row> + <row> + <entry><command>X4</command></entry> + <entry></entry> + <entry>Usually adds both busy signal and dial tone detection</entry> + </row> + <row> + <entry><command>Z0</command> or <command>Z</command></entry> + <entry>Reset</entry> + <entry>Reset modem to stored configuration. Use <command>Z0</command>, + <command>Z1</command> &etc; for multiple profiles. This is the same as + <command>&F</command> for factory default on modems without + <acronym>NVRAM</acronym> (non voltaile memory)</entry> + </row> + </tbody> + </tgroup> + </table> + </sect1> + + <sect1 id="hayes-extended-commands"> + <title>The Extended Hayes Command Set</title><subtitle>Ampersand Commands</subtitle> + + <table> + <title>The Extended Hayes Command Set</title> + <tgroup cols="3"> + <thead> + <row> + <entry>Command</entry> + <entry>Description</entry> + <entry>Comments</entry> + </row> + </thead> + <tbody> + <row> + <entry><command>&B0</command> or <command>&B</command></entry> + <entry>Retrain Parameters</entry> + <entry>Disable auto retrain function</entry> + </row> + <row> + <entry><command>&B1</command></entry> + <entry>Retrain Parameters</entry> + <entry>Enable auto retrain function</entry> + </row> + <row> + <entry><command>&B2</command></entry> + <entry>Retrain Parameters</entry> + <entry>Enable auto retrain, but disconnect if no line improvement over + the period dictated by <link + linkend="hayes-s7"><varname>S7</varname></link></entry> +</row> + <row> + <entry><command>&C0</command> or <command>&C1</command></entry> + <entry>Carrier detect</entry> + <entry>Signal always on</entry> + </row> + <row> + <entry><command>&C1</command></entry> + <entry>Carrier detect</entry> + <entry>Indicates remote carrier (usual preferred default)</entry> + </row> + <row> + <entry><command>&D0</command> or <command>&D</command></entry> + <entry>Data Terminal Ready (<acronym>DTR</acronym></entry> + <entry>Signal ignored (This is modem specific, you must see your manual + for information on this one!)</entry> + </row> + <row> + <entry><command>&D1</command></entry> + <entry>Data Terminal Ready (<acronym>DTR</acronym></entry> + <entry>If <acronym>DTR</acronym> goes from On to Off the modem goes into + command mode (Some modems only)</entry> + </row> + <row> + <entry><command>&D2</command></entry> + <entry>Data Terminal Ready (<acronym>DTR</acronym></entry> + <entry>Some modems hang up on <acronym>DTR</acronym> On to Off transition + (This is the usual preferred default)</entry> + </row> + <row> + <entry><command>&D3</command></entry> + <entry>Data Terminal Ready (<acronym>DTR</acronym></entry> + <entry>Hang up, reset the modem, and return to command mode upon + <acronym>DTR</acronym></entry> + </row> + <row> + <entry><command>&F0</command> or <command>&F</command></entry> + <entry>Factory defaults</entry> + <entry><para>Generic Hayes-compatible defaults. </para><para>This is + usually a good thing to use in your init string, since the + <command>&F1</command>-<command>&F3</command> settings can vary + among modems, and they may actually be the cause of connection + problems. (Since you never know exactly what Brand X's + <command>&F2</command> really changes.</para><para>On the other hand, + it pays to try out the other options below; many people's problems can be + solved by replacing a complicated init string with a simple + <command>&F2</command> or the like. However, if you're building an + init string, it's best to start with a simple <command>&F</command>, + and not use the <quote>customized</quote> form of + defaults.</para></entry> + </row> + <row> + <entry><command>&F1</command></entry> + <entry>Factory Defaults</entry> + <entry>Factory Defaults tailored to an IBM <acronym>PC</acronym> + compatible user</entry> + </row> + <row> + <entry><command>&F2</command></entry> + <entry>Factory Defaults</entry> + <entry>Factory defaults for a Mac w/software handshaking</entry> + </row> + <row> + <entry><command>&F3</command></entry> + <entry>Factory Defaults</entry> + <entry>Factory defaults for a Mac w/hardware handshaking</entry> + </row> + <row> + <entry><command>&G0</command> or <command>&G</command></entry> + <entry>Guard tones</entry> + <entry>Disable guard tones</entry> + </row> + <row> + <entry><command>&K0</command> or <command>&K</command></entry> + <entry>Local flow control</entry> + <entry>Disable local flow control</entry> + </row> + <row> + <entry><command>&K1</command></entry> + <entry>Local flow control</entry> + <entry>Enable RTS/CTS hardware local flow control</entry> + </row> + <row> + <entry><command>&K2</command></entry> + <entry>Local flow control</entry> + <entry>Enable XON/XOFF software local flow control</entry> + </row> + <row> + <entry><command>&K3</command></entry> + <entry>Local flow control</entry> + <entry>Enable RTS/CTS hardware local flow control</entry> + </row> + <row> + <entry><command>&K4</command></entry> + <entry>Local flow control</entry> + <entry>Enable XON/XOFF software local flow control</entry> + </row> + <row> + <entry><command>&L0</command> or <command>&L</command></entry> + <entry>Dial mode</entry> + <entry>Select dial-up mode</entry> + </row> + <row> + <entry><command>&M0</command> or <command>&M</command></entry> + <entry>Error control mode</entry> + <entry>Select asynchronous non-<acronym>EC</acronym> mode (the same as + <command>&Q0</command>)</entry> + </row> + <row> + <entry><command>&P0</command> or <command>&P</command></entry> + <entry>Pulse dialing ratio</entry> + <entry>U.S./Canada pulse dialing 39% make / 61% break ratio</entry> + </row> + <row> + <entry><command>&P1</command></entry> + <entry>Pulse dialing ratio</entry> + <entry>U.K./Hong Kong pulse dialing 33% make / 67% break ratio</entry> + </row> + <row> + <entry><command>&Q0</command> or <command>&Q</command></entry> + <entry>Error control mode</entry> + <entry>Asynchronous non-<acronym>EC</acronym> more. No data + buffering. <acronym>ASB</acronym> disabled.</entry> + </row> + <row> + <entry><command>&Q5</command></entry> + <entry>Error control mode</entry> + <entry>Select V.42 <acronym>EC</acronym> operation (requires flow + control)</entry> + </row> + <row> + <entry><command>&Q6</command></entry> + <entry>Error control mode</entry> + <entry>Asynchronous mode with <acronym>ASB</acronym> (requires flow + control)</entry> + </row> + <row> + <entry><command>&Q8</command></entry> + <entry>Error control mode</entry> + <entry>Select alternate <acronym>EC</acronym> protocol + (<acronym>MNP</acronym>)</entry> + </row> + <row> + <entry><command>&Q9</command></entry> + <entry>Error control mode</entry> + <entry>Conditional data compression: V.42bis = yes, MNP5 = no.</entry> + </row> + <row> + <entry><command>&S0</command> or <command>&S</command></entry> + <entry><acronym>DSR</acronym> action select</entry> + <entry>Always on (default)</entry> + </row> + <row> + <entry><command>&S1</command></entry> + <entry><acronym>DSR</acronym> action select</entry> + <entry>Follows <acronym>EIA</acronym> specification (Active following + carrier tone, and until carrier is lost.)</entry> + </row> + <row> + <entry><command>&T0</command> or <command>&T</command></entry> + <entry>Self test</entry> + <entry>Model specific self test on some modems</entry> + </row> + <row> + <entry><command>&U0</command> or <command>&U</command></entry> + <entry>Trellis code modulation</entry> + <entry>Enable V.32 <acronym>TCM</acronym></entry> + </row> + <row> + <entry><command>&U1</command></entry> + <entry>Trellis code modulation</entry> + <entry>Disable V.32 <acronym>TCM</acronym></entry> + </row> + <row> + <entry><command>&V0</command> or <command>&V1</command></entry> + <entry>View active</entry> + <entry>(and often stored) configuration profile settings (or + <command>ATI4</command></entry> + </row> + <row> + <entry><command>&W0</command> or <command>&W</command></entry> + <entry>Store profile</entry> + <entry>In <acronym>NVRAM</acronym> (<command>&W0</command>, + <command>&W1</command> etc. for multiple profiles) Some settings + cannot be stored. These often don't show on <command>&V</command> or + <command>ATI4</command></entry> + </row> + <row> + <entry><command>&Y0</command> or <command>&Y</command></entry> + <entry>Select configuration loaded at power-up</entry> + <entry>Load profile 0 (default)</entry> + </row> + <row> + <entry><command>&Y1</command></entry> + <entry>Select configuration loaded at power-up</entry> + <entry>Load profile 1</entry> + </row> + <row> + <entry><command>&Z<replaceable>n</replaceable>=<replaceable>x</replaceable></command></entry> + <entry>Soft reset and load stored profile number + <replaceable>n</replaceable></entry> + <entry>Note that all items after the <command>&Z</command> on the + command line are ignored</entry> + </row> + </tbody> + </tgroup> + </table> + + </sect1> + + <sect1 id="hayes-backslash-commands"> + <title>Backslash and Percent Commands</title> + + <table> + <title>Backslash and Percent Commands</title> + <tgroup cols="3"> + <thead> + <row> + <entry>Command</entry> + <entry>Description</entry> + <entry>Comments</entry> + </row> + </thead> + <tbody> + <row> + <entry><command>\A0</command> or <command>\A</command></entry> + <entry>Character maximum <acronym>MNP</acronym> block size</entry> + <entry>64 character maximum</entry> + </row> + <row> + <entry><command>\A1</command></entry> + <entry>Character maximum <acronym>MNP</acronym> block size</entry> + <entry>128 character maximum</entry> + </row> + <row> + <entry><command>\A2</command></entry> + <entry>Character maximum <acronym>MNP</acronym> block size</entry> + <entry>192 character maximum</entry> + </row> + <row> + <entry><command>\A3</command></entry> + <entry>Character maximum <acronym>MNP</acronym> block size</entry> + <entry>256 character maximum</entry> + </row> + <row> + <entry><command>%C0</command> or + <command>%C</command></entry> + <entry>Data Compression Enable/Disable</entry> + <entry>Disabled</entry> + </row> + <row> + <entry><command>%C1</command></entry> + <entry>Data Compression Enable/Disable</entry> + <entry>MNP5 enabled</entry> + </row> + <row> + <entry><command>%C2</command></entry> + <entry>Data Compression Enable/Disable</entry> + <entry>V.42bis (<acronym>BTLZ</acronym>) Enabled</entry> + </row> + <row> + <entry><command>%C3</command></entry> + <entry>Data Compression Enable/Disable</entry> + <entry>MNP5 & V.42bis (<acronym>BTLZ</acronym>) Enabled</entry> + </row> + <row> + <entry><command>%D0</command> or + <command>%D</command></entry> + <entry>Data compression</entry> + <entry>512 BLTZ dictionary size</entry> + </row> + <row> + <entry><command>%D1</command></entry> + <entry>Data compression</entry> + <entry>1024 BLTZ dictionary size</entry> + </row> + <row> + <entry><command>%D2</command></entry> + <entry>Data compression</entry> + <entry>2048 BLTZ dictionary size</entry> + </row> + <row> + <entry><command>%D3</command></entry> + <entry>Data compression</entry> + <entry>4096 BLTZ dictionary size</entry> + </row> + <row> + <entry><command>%E0</command> or + <command>%E1</command></entry> + <entry>Escape method</entry> + <entry>ESCAPE DISABLED</entry> + </row> + <row> + <entry><command>%E1</command></entry> + <entry>Escape method</entry> + <entry><command>+++AT</command> method (default)</entry> + </row> + <row> + <entry><command>%E2</command></entry> + <entry>Escape method</entry> + <entry><computeroutput>Break</computeroutput> <command>AT</command> + method</entry> + </row> + <row> + <entry><command>%E3</command></entry> + <entry>Escape method</entry> + <entry>BOTH methods enabled</entry> + </row> + <row> + <entry><command>%E4</command></entry> + <entry>Escape method</entry> + <entry>Disable <computeroutput>OK</computeroutput> to + <command>+++</command></entry> + </row> + <row> + <entry><command>%E5</command></entry> + <entry>Escape method</entry> + <entry>Enable <computeroutput>OK</computeroutput> to + <command>+++</command></entry> + </row> + <row> + <entry><command>\J0</command> or <command>\J</command></entry> + <entry><acronym>DTE</acronym> Auto Rate Adjustment</entry> + <entry>Disabled</entry> + </row> + <row> + <entry><command>\J1</command></entry> + <entry><acronym>DTE</acronym> Auto Rate Adjustment</entry> + <entry><acronym>DTE</acronym> rate is adjusted to match carrier rate.</entry> + </row> + <row> + <entry><command>\N0</command> or <command>\N</command></entry> + <entry>Connection type</entry> + <entry>Normal connection (see below for definitions)</entry> + </row> + <row> + <entry><command>\N1</command></entry> + <entry>Connection type</entry> + <entry>Direction connection</entry> + </row> + <row> + <entry><command>\N2</command></entry> + <entry>Connection type</entry> + <entry><acronym>MNP</acronym> Auto-reliable connection</entry> + </row> + <row> + <entry><command>\N3</command></entry> + <entry>Connection type</entry> + <entry>Auto-reliable connection</entry> + </row> + <row> + <entry><command>\N4</command></entry> + <entry>Connection type</entry> + <entry>V.42bis reliable link with phase detection</entry> + </row> + <row> + <entry><command>\N5</command></entry> + <entry>Connection type</entry> + <entry>V.42bis auto-reliable link with phase detection</entry> + </row> + <row> + <entry><command>\N6</command></entry> + <entry>Connection type</entry> + <entry>V.42 reliable link with phase detection</entry> + </row> + <row> + <entry><command>\N7</command></entry> + <entry>Connection type</entry> + <entry>V.42 auto-reliable link with phase detection</entry> + </row> + </tbody> + </tgroup> + </table> + +<para>A direct connection is a simple straight-through connection without any +error connection or data compression. In this case, the computer-to-modem and +modem-to-modem speeds must be identical.</para> + +<para>A normal connection uses flow control (either software or hardware) to +buffer the data being sent or received, so that the modem can transmit data at a +different rate than the computer is actually sending or receiving it. For +example, a computer may send actual data at 57kbps, but using compression, the +modem only actually sends 28.8kbps. This is the mode use by most modems.</para> + +<para>A reliable connection is a type of normal connection; if, for some reason, +data compression or error correction cannot be established or maintained, the +connection will hang up. (In essence, such a modem ensures that all connections +are reliable, for it will hang up if the connection isn't.)</para> + +<para>Likewise, an auto-reliable connection is virtually the same, except that +the modem will try to renegotiate the connection in order to establish a +reliable connection. Again, this is the mode that most modems use.</para> + +</sect1> + +<sect1 id="hayes-sregisters"> +<title>S-Registers</title> + + <table> + <title>S Registers</title> + <tgroup cols="4"> + <thead> + <row> + <entry>Register</entry> + <entry>Range</entry> + <entry>Default</entry> + <entry>Function</entry> + </row> + </thead> + <tbody> + <row> + <entry><varname>S0</varname></entry> + <entry>0-255 rings</entry> + <entry>1-2</entry> + <entry>Answer on ring number. Don't answer if 0</entry> + </row> + <row> + <entry><varname>S1</varname></entry> + <entry>0-255 rings</entry> + <entry>0</entry> + <entry>if <varname>S0</varname> is greater than + <returnvalue>0</returnvalue> this register counts the incoming + rings.</entry> + </row> + <row> + <entry><varname>S2</varname></entry> + <entry>0-127 <acronym>ASCII</acronym></entry> + <entry>43 +</entry> + <entry>Escape to command mode character</entry> + </row> + <row> + <entry><varname>S2</varname></entry> + <entry>>127</entry> + <entry></entry> + <entry>no ESC</entry> + </row> + <row> + <entry><varname>S3</varname></entry> + <entry>0-127 <acronym>ASCII</acronym></entry> + <entry>13 CR</entry> + <entry>Carriage return character</entry> + </row> + <row> + <entry><varname>S4</varname></entry> + <entry>0-127 <acronym>ASCII</acronym></entry> + <entry>10 LF</entry> + <entry>Line feed character</entry> + </row> + <row> + <entry><varname>S5</varname></entry> + <entry>0-32, 127 <acronym>ASCII</acronym></entry> + <entry>8 BS</entry> + <entry>Backspace character</entry> + </row> + <row> + <entry><varname>S6</varname></entry> + <entry>2-255 seconds</entry> + <entry>2</entry> + <entry>Dial tone wait time (blind dialing, see <link + linkend="hayes-basic-x1">X<replaceable>n</replaceable></link></entry> + </row> + <row> + <entry><anchor id="hayes-s7"/><varname>S7</varname></entry> + <entry>1-255 seconds</entry> + <entry>30-60</entry> + <entry>Wait time for remote carrier</entry> + </row> + <row> + <entry><varname>S8</varname></entry> + <entry>0-255 seconds</entry> + <entry>2</entry> + <entry>Comma pause time used in dialing</entry> + </row> + <row> + <entry><varname>S9</varname></entry> + <entry>1-255 1/10ths second</entry> + <entry>6</entry> + <entry>Carrier detect time required for recognition</entry> + </row> + <row> + <entry><varname>S10</varname></entry> + <entry>1-255 1/10ths second</entry> + <entry>7-14</entry> + <entry>Time between loss of carrier and hangup</entry> + </row> + <row> + <entry><varname>S11</varname></entry> + <entry>50-255 milliseconds</entry> + <entry>70-95</entry> + <entry>Duration and spacing of tones when tone dialing</entry> + </row> + <row> + <entry><varname>S12</varname></entry> + <entry>0-255 1/50th seconds</entry> + <entry>50</entry> + <entry>Guard time for pause around <command>+++</command> command + sequence</entry> + </row> + <row> + <entry><varname>S36</varname></entry> + <entry><para>Fallback options when error correction link + fails:</para><itemizedlist> + <listitem><para>0 - Disconnect</para> + </listitem> + <listitem><para>1 - Establish Direct Connection</para> + </listitem> + <listitem><para>3 - Establish Normal Connection</para> + </listitem> + <listitem><para>4 - Establish an <acronym>MNP</acronym> connection if + possible, else disconnect</para> + </listitem> + <listitem><para>5 - Establish an <acronym>MNP</acronym> connection if + possible, else Direct Connection.</para> + </listitem> + <listitem><para>7 - Establish an <acronym>MNP</acronym> connection if + possible, else Normal connection</para> + </listitem> + </itemizedlist></entry> + <entry>7</entry> + <entry>Negotiation Failure Treatment</entry> + </row> + <row> + <entry><anchor id="hayes-s37"/><varname>S37</varname></entry> + <entry><itemizedlist> + <listitem><para><returnvalue>1</returnvalue> = 300 bps</para> + </listitem> + <listitem><para><returnvalue>5</returnvalue> = 1200 bps</para> + </listitem> + <listitem><para><returnvalue>6</returnvalue> = 2400 bps</para> + </listitem> + <listitem><para><returnvalue>7</returnvalue> = 1200/75 bps (v.23 + mode)</para> + </listitem> + <listitem><para><returnvalue>8</returnvalue> = 4800 bps</para> + </listitem> + <listitem><para><returnvalue>9</returnvalue> = 9600 bps</para> + </listitem> + <listitem><para><returnvalue>10</returnvalue> = 12000 bps</para> + </listitem> + <listitem><para><returnvalue>11</returnvalue> = 14400 bps</para> + </listitem> + <listitem><para><returnvalue>12</returnvalue> = 7200 bps</para> + </listitem> + </itemizedlist></entry> + <entry>0</entry> + <entry>Negotiation Speed (Initial handshake)</entry> + </row> + </tbody> + </tgroup> + </table> + +<para>Many modems have dozens, even hundreds, of S registers, but only the first +dozen or so are fairly standard. They are changed with a command like +<command>ATS<replaceable>n</replaceable>=<replaceable>N</replaceable></command>, +and examined with <command>ATS<replaceable>n</replaceable>?</command> (⪚ +<userinput><command>AT</command> <command>S10</command><option>=70</option> +<command>S1?</command></userinput> would tell the modem not to hang up for seven +seconds should it not hear the answering modem, and return the number of times +the phone last rang.)</para> + +</sect1> +</appendix> |