interfacing the serial - 1.htm

软硬件结合

    style='font-family:Arial'>Pin 1 <o:p></o:p></span></p>
    </td>
    <td width="17%" style='width:17.92%;border:inset .75pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal align=center style='text-align:center'><span lang=EN-US
    style='font-family:Arial'>CD <o:p></o:p></span></p>
    </td>
    <td width="54%" style='width:54.28%;border:inset .75pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal align=center style='text-align:center'><span lang=EN-US
    style='font-family:Arial'>Carrier Detect </span><span style='mso-ascii-font-family:
    Arial;mso-hansi-font-family:Arial;mso-bidi-font-family:Arial'>载波侦查</span><span
    lang=EN-US style='font-family:Arial'><o:p></o:p></span></p>
    </td>
   </tr>
   <tr>
    <td width="11%" style='width:11.98%;border:inset .75pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal align=center style='text-align:center'><span lang=EN-US
    style='font-family:Arial'>Pin 20 <o:p></o:p></span></p>
    </td>
    <td width="14%" style='width:14.3%;border:inset .75pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal align=center style='text-align:center'><span lang=EN-US
    style='font-family:Arial'>Pin 4 <o:p></o:p></span></p>
    </td>
    <td width="17%" style='width:17.92%;border:inset .75pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal align=center style='text-align:center'><span lang=EN-US
    style='font-family:Arial'>DTR <o:p></o:p></span></p>
    </td>
    <td width="54%" style='width:54.28%;border:inset .75pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal align=center style='text-align:center'><span lang=EN-US
    style='font-family:Arial'>Data Terminal Ready </span><span
    style='mso-ascii-font-family:Arial;mso-hansi-font-family:Arial;mso-bidi-font-family:
    Arial'>终端就绪</span><span lang=EN-US style='font-family:Arial'><o:p></o:p></span></p>
    </td>
   </tr>
   <tr>
    <td width="11%" style='width:11.98%;border:inset .75pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal align=center style='text-align:center'><span lang=EN-US
    style='font-family:Arial'>Pin 22 <o:p></o:p></span></p>
    </td>
    <td width="14%" style='width:14.3%;border:inset .75pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal align=center style='text-align:center'><span lang=EN-US
    style='font-family:Arial'>Pin 9 <o:p></o:p></span></p>
    </td>
    <td width="17%" style='width:17.92%;border:inset .75pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal align=center style='text-align:center'><span lang=EN-US
    style='font-family:Arial'>RI <o:p></o:p></span></p>
    </td>
    <td width="54%" style='width:54.28%;border:inset .75pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal align=center style='text-align:center'><span lang=EN-US
    style='font-family:Arial'>Ring Indicator </span><span style='mso-ascii-font-family:
    Arial;mso-hansi-font-family:Arial;mso-bidi-font-family:Arial'>响铃指示</span><span
    lang=EN-US style='font-family:Arial'><o:p></o:p></span></p>
    </td>
   </tr>
  </table>
  </div>
  <p class=MsoNormal align=center style='margin-left:36.0pt;text-align:center'><span
  lang=EN-US style='font-size:10.0pt;font-family:Arial'>Table 1 : D Type 9 Pin
  and D Type 25 Pin Connectors <o:p></o:p></span></p>
  <p style='margin-left:36.0pt'><a name=3><span lang=EN-US style='font-size:
  13.5pt'>Pin Functions</span></a><span style='font-size:13.5pt;font-family:
  宋体;mso-ascii-font-family:Arial;mso-hansi-font-family:Arial'>引脚功能</span></p>
  <div class=MsoNormal align=center style='margin-left:36.0pt;text-align:center'><span
  lang=EN-US style='font-family:Arial'>
  <hr size=2 width="100%" align=center>
  </span></div>
  <table border=0 cellpadding=0 style='mso-cellspacing:1.5pt;margin-left:36.0pt;
   mso-padding-alt:0cm 0cm 0cm 0cm'>
   <tr>
    <td colspan=2 valign=top style='padding:0cm 0cm 0cm 0cm'>
    <p class=MsoNormal><b><span lang=EN-US style='font-family:Arial'>Abbreviation</span></b><span
    lang=EN-US style='font-family:Arial'><o:p></o:p></span></p>
    </td>
    <td width=753 style='width:565.05pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><b><span lang=EN-US style='font-family:Arial'>Function</span></b><span
    lang=EN-US style='font-family:Arial'><o:p></o:p></span></p>
    </td>
   </tr>
   <tr>
    <td style='padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>&nbsp;&nbsp;3<o:p></o:p></span></p>
    </td>
    <td valign=top style='padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>TD<o:p></o:p></span></p>
    </td>
    <td width=753 style='width:565.05pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>Serial Data
    Output (TXD)<o:p></o:p></span></p>
    </td>
   </tr>
   <tr>
    <td style='padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>&nbsp; 2<o:p></o:p></span></p>
    </td>
    <td valign=top style='padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>RD<o:p></o:p></span></p>
    </td>
    <td width=753 style='width:565.05pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>Serial Data
    Input (RXD)<o:p></o:p></span></p>
    </td>
   </tr>
   <tr>
    <td style='padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>&nbsp;&nbsp;8<o:p></o:p></span></p>
    </td>
    <td valign=top style='padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>CTS<o:p></o:p></span></p>
    </td>
    <td width=753 style='width:565.05pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>This line
    indicates that the Modem is ready to exchange data</span><span
    style='mso-ascii-font-family:Arial;mso-hansi-font-family:Arial;mso-bidi-font-family:
    Arial'>　　通知</span><span lang=EN-US style='font-family:Arial'>UART</span><span
    style='mso-ascii-font-family:Arial;mso-hansi-font-family:Arial;mso-bidi-font-family:
    Arial'>：</span><span lang=EN-US style='font-family:Arial'>Modem</span><span
    style='mso-ascii-font-family:Arial;mso-hansi-font-family:Arial;mso-bidi-font-family:
    Arial'>准备好交换数据</span><span lang=EN-US style='font-family:Arial'><o:p></o:p></span></p>
    </td>
   </tr>
   <tr>
    <td style='padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>&nbsp;&nbsp;1<o:p></o:p></span></p>
    </td>
    <td valign=top style='padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>CD<o:p></o:p></span></p>
    </td>
    <td width=753 style='width:565.05pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>When the
    modem detects a &quot;Carrier&quot; from the modem at the other end of the
    phone line, this Line becomes active.<o:p></o:p></span></p>
    </td>
   </tr>
   <tr>
    <td style='padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>&nbsp;&nbsp;6<o:p></o:p></span></p>
    </td>
    <td valign=top style='padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>DSR<o:p></o:p></span></p>
    </td>
    <td width=753 style='width:565.05pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal style='text-indent:12.0pt;mso-char-indent-count:1.0;
    mso-char-indent-size:12.0pt'><span lang=EN-US style='font-family:Arial'><span
    style="mso-spacerun: yes">&nbsp;</span>tells the UART that the modem is
    ready to establish a link</span><span style='mso-ascii-font-family:Arial;
    mso-hansi-font-family:Arial;mso-bidi-font-family:Arial'>　　通知</span><span
    lang=EN-US style='font-family:Arial'>UART</span><span style='mso-ascii-font-family:
    Arial;mso-hansi-font-family:Arial;mso-bidi-font-family:Arial'>：</span><span
    lang=EN-US style='font-family:Arial'>Modem</span><span style='mso-ascii-font-family:
    Arial;mso-hansi-font-family:Arial;mso-bidi-font-family:Arial'>准备好建立连接</span><span
    lang=EN-US style='font-family:Arial'>.<o:p></o:p></span></p>
    </td>
   </tr>
   <tr>
    <td style='padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>&nbsp;&nbsp;4<o:p></o:p></span></p>
    </td>
    <td valign=top style='padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>DTR<o:p></o:p></span></p>
    </td>
    <td width=753 style='width:565.05pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal style='text-indent:12.0pt;mso-char-indent-count:1.0;
    mso-char-indent-size:12.0pt'><span lang=EN-US style='font-family:Arial'><span
    style="mso-spacerun: yes">&nbsp;</span>tells the Modem that the UART is
    ready to link</span><span style='mso-ascii-font-family:Arial;mso-hansi-font-family:
    Arial;mso-bidi-font-family:Arial'>　　　　　　　通知</span><span lang=EN-US
    style='font-family:Arial'>Modem</span><span style='mso-ascii-font-family:
    Arial;mso-hansi-font-family:Arial;mso-bidi-font-family:Arial'>：</span><span
    lang=EN-US style='font-family:Arial'>UART</span><span style='mso-ascii-font-family:
    Arial;mso-hansi-font-family:Arial;mso-bidi-font-family:Arial'>准备好</span><span
    lang=EN-US style='font-family:Arial'>.<o:p></o:p></span></p>
    </td>
   </tr>
   <tr>
    <td style='padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>&nbsp;&nbsp;7<o:p></o:p></span></p>
    </td>
    <td valign=top style='padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>RTS<o:p></o:p></span></p>
    </td>
    <td width=753 style='width:565.05pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal style='text-indent:12.0pt;mso-char-indent-count:1.0;
    mso-char-indent-size:12.0pt'><span lang=EN-US style='font-family:Arial'><span
    style="mso-spacerun: yes">&nbsp;</span>informs the Modem that the UART is
    ready to exchange data</span><span style='mso-ascii-font-family:Arial;
    mso-hansi-font-family:Arial;mso-bidi-font-family:Arial'>　通知</span><span
    lang=EN-US style='font-family:Arial'>Modem</span><span style='mso-ascii-font-family:
    Arial;mso-hansi-font-family:Arial;mso-bidi-font-family:Arial'>：</span><span
    lang=EN-US style='font-family:Arial'>UART</span><span style='mso-ascii-font-family:
    Arial;mso-hansi-font-family:Arial;mso-bidi-font-family:Arial'>准备好交换数据</span><span
    lang=EN-US style='font-family:Arial'>.<o:p></o:p></span></p>
    </td>
   </tr>
   <tr>
    <td style='padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>&nbsp;&nbsp;9<o:p></o:p></span></p>
    </td>
    <td valign=top style='padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>RI<o:p></o:p></span></p>
    </td>
    <td width=753 style='width:565.05pt;padding:.75pt .75pt .75pt .75pt'>
    <p class=MsoNormal><span lang=EN-US style='font-family:Arial'>Goes active
    when modem detects a ringing signal from the PSTN.<o:p></o:p></span></p>
    </td>
   </tr>
  </table>
  <p style='margin-left:36.0pt'><a name=4><span lang=EN-US style='font-size:
  13.5pt'>Null Modems</span><span lang=EN-US> </span></a><span
  style='mso-bookmark:4'><span style='font-family:宋体;mso-ascii-font-family:
  Arial;mso-hansi-font-family:Arial'>无调制解调器连接</span></span></p>
  <span style='mso-bookmark:4'></span>
  <div class=MsoNormal align=center style='margin-left:36.0pt;text-align:center'><span
  style='mso-bookmark:4'><span lang=EN-US style='font-family:Arial'>
  <hr size=2 width="100%" align=center>
  </span></span></div>
  <span style='mso-bookmark:4'></span>
  <p style='margin-left:36.0pt'><span lang=EN-US>A Null Modem is used to connect