键盘.htm

键盘 键盘是用户对电脑进行输入的最常用工具

face=Tahoma><SPAN lang=EN-US>ALT</SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">、</SPAN><FONT face=Tahoma><SPAN 
lang=EN-US>CONTROL</SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">和</SPAN><FONT 
face=Tahoma><SPAN lang=EN-US>SHIFT</SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">。为</SPAN><FONT face=Tahoma><SPAN lang=EN-US>CAPS 
LOCK </SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">、</SPAN><FONT 
face=Tahoma><SPAN lang=EN-US>NUM LOCK </SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">和</SPAN><FONT face=Tahoma><SPAN lang=EN-US>SCROLL 
LOCK</SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">各保留一位也是不错的主意。本指南将解释如何设置键盘灯，但实际代码的书写工作将留给你。</SPAN></P>
<P><SPAN 
style="FONT-FAMILY: Tahoma">键盘通过主板上一个特别的微控制芯片与计算机相连。键盘控制芯片有两个通道：一个用于键盘，一个用于鼠标。同样注意到，通过键盘控制芯片，你可以使能处理器的</SPAN><FONT 
face=Tahoma><SPAN lang=EN-US>A20</SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">地址线，从而可以越过</SPAN><FONT face=Tahoma><SPAN 
lang=EN-US>1MB</SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">标记访问内存（</SPAN><FONT face=Tahoma><SPAN 
lang=EN-US>GRUB</SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">使能了这个，所以你不比再为此担心）。键盘控制器作为一个系统可访问的设备，在</SPAN><FONT 
face=Tahoma><SPAN lang=EN-US>I/O</SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">总线上有一个地址，我们可以用这个地址对其进行访问和控制。键盘有两个主要的寄存器：一个在</SPAN><FONT 
face=Tahoma><SPAN lang=EN-US>0x60</SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">的数据寄存器和一个在</SPAN><FONT face=Tahoma><SPAN 
lang=EN-US>0x64</SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">的控制寄存器。任何键盘想送给计算机的东西都存储在数据寄存器。键盘在有数据可读时将激活</SPAN><FONT 
face=Tahoma><SPAN lang=EN-US>IRQ1</SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">。看看下面的程序：</SPAN></P>
<TABLE id=table3 style="BORDER-COLLAPSE: collapse" width="100%" border=1>
  <TBODY>
  <TR>
    <TD><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Courier New; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><FONT face=Tahoma><SPAN lang=EN-US>/* </SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">处理键盘中断</SPAN><FONT face=Tahoma><SPAN lang=EN-US> */</SPAN></FONT></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Tahoma; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><SPAN lang=EN-US>void keyboard_handler(struct regs *r)</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Tahoma; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><SPAN lang=EN-US>{</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Tahoma; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><SPAN lang=EN-US>    unsigned char scancode;</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Tahoma; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><SPAN lang=EN-US>&nbsp;</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Courier New; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><FONT face=Tahoma><SPAN lang=EN-US>    /* </SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">从键盘的数据缓冲中读</SPAN><FONT face=Tahoma><SPAN lang=EN-US> */</SPAN></FONT></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Tahoma; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><SPAN lang=EN-US>    scancode = inportb(0x60);</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Tahoma; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><SPAN lang=EN-US>&nbsp;</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Courier New; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><FONT face=Tahoma><SPAN lang=EN-US>    /* </SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">如果我们从键盘读入的字节的顶位被设置了，就意味着一个键刚被释放。</SPAN><FONT face=Tahoma><SPAN lang=EN-US> */</SPAN></FONT></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Tahoma; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><SPAN lang=EN-US>    if (scancode &amp; 0x80)</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Tahoma; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><SPAN lang=EN-US>    {</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Courier New; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><FONT face=Tahoma><SPAN lang=EN-US>        /* </SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">你可以用这个来测试用户是否释放了</SPAN><FONT face=Tahoma><SPAN lang=EN-US>ALT</SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">、</SPAN><FONT face=Tahoma><SPAN lang=EN-US>SHIFT</SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">、</SPAN><FONT face=Tahoma><SPAN lang=EN-US>CONTROL</SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">……等键。</SPAN><FONT face=Tahoma><SPAN lang=EN-US> */</SPAN></FONT></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Tahoma; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><SPAN lang=EN-US>    }</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Tahoma; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><SPAN lang=EN-US>    else</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Tahoma; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><SPAN lang=EN-US>    {</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Courier New; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><FONT face=Tahoma><SPAN lang=EN-US>        /* </SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">这里，一个键被按下。请注意如果你按住一个键，你就将重复地产生按键中断。</SPAN><FONT face=Tahoma><SPAN lang=EN-US> */</SPAN></FONT></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Tahoma; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><SPAN lang=EN-US>&nbsp;</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Courier New; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><FONT face=Tahoma><SPAN lang=EN-US>        /* </SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">为了说明这是如何工作的，我们简单地把键盘扫描码转换成</SPAN><FONT face=Tahoma><SPAN lang=EN-US>ASCII</SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">值，</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Courier New; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><FONT face=Tahoma><SPAN lang=EN-US>        *  </SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">然后把它显示到屏幕。你可能想用别的做法，比如用一些标志来测试</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Courier New; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><FONT face=Tahoma><SPAN lang=EN-US>        *  SHIFT</SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">是否被按下，用一个不同的布局，或者添加另外的</SPAN><FONT face=Tahoma><SPAN lang=EN-US>128</SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">个入口</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Courier New; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><FONT face=Tahoma><SPAN lang=EN-US>        *  </SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">到上面的布局来对应</SPAN><FONT face=Tahoma><SPAN lang=EN-US>SHIFT</SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">被按住的情况。如果使用更大的检查表对应</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Courier New; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><FONT face=Tahoma><SPAN lang=EN-US>        *  SHIFT</SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">被按下的情况，查找时你需要在扫描码上加上</SPAN><FONT face=Tahoma><SPAN lang=EN-US>128</SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">。</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Tahoma; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><SPAN lang=EN-US>     */</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Tahoma; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><SPAN lang=EN-US>        putch(kbdus[scancode]);</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Tahoma; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><SPAN lang=EN-US>    }</SPAN></FONT></PRE><PRE style="FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt 24pt; FONT-FAMILY: Tahoma; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><FONT color=#800000><SPAN lang=EN-US>}</SPAN></FONT></PRE></TD></TR>
  <TR>
    <TD><B><SPAN style="FONT-FAMILY: Tahoma"><FONT 
      size=2>看起来很复杂，但</FONT></SPAN><FONT size=2><FONT face=Tahoma><SPAN 
      lang=EN-US>80</SPAN></FONT><SPAN style="FONT-FAMILY: Tahoma">％都是注释<SPAN 
      lang=en-us>。</SPAN>把它添加到“</SPAN><FONT face=Tahoma><SPAN 
      lang=EN-US>kb.c</SPAN></FONT></FONT><SPAN 
      style="FONT-FAMILY: Tahoma"><FONT 
size=2>”</FONT></SPAN></B></TD></TR></TBODY></TABLE>
<P><SPAN style="FONT-FAMILY: Tahoma">就像你看到的一样，键盘将会产生一个</SPAN><FONT 
face=Tahoma><SPAN lang=EN-US>IRQ1</SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">来告诉我们它有数据就绪可读。键盘的数据寄存器在</SPAN><FONT 
face=Tahoma><SPAN lang=EN-US>0x60</SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">。当</SPAN><FONT face=Tahoma><SPAN 
lang=EN-US>IRQ</SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">发生时，我们调用处理程序从</SPAN><FONT face=Tahoma><SPAN 
lang=EN-US>0x60</SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">端口读。我们读到的数据时键盘的扫描码。在本例中，我们测试键是被按下还是被释放。如果只是按下，我们把扫描码转换成</SPAN><FONT 
face=Tahoma><SPAN lang=EN-US>ASCII</SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">，并用一行把那个字符打印处理。编写“</SPAN><FONT face=Tahoma><SPAN 
lang=EN-US>keyboard_install</SPAN></FONT><SPAN 
style="FONT-FAMILY: Tahoma">”函数，调用“</SPAN><FONT face=Tahoma><SPAN 
lang=EN-US>irq_install_handler</SPAN></FONT><SPAN