⭐ 欢迎来到虫虫下载站！ | 📦 资源下载 📁 资源专辑 ℹ️ 关于我们
⭐ 虫虫下载站
📤 上传资源

📄 booting-a20_4.htm

📁 编写自己的操作系统
💻 HTM
📖 第 1 页 / 共 4 页
字号:
🔍
1234 
style="FONT: 7pt 'Times New Roman'"><FONT 
size=3>&nbsp;&nbsp;&nbsp;</FONT></SPAN></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">等待，直到<FONT 
face="Times New Roman TUR">8042 Output buffer</FONT>有数据为止；</SPAN></FONT></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><FONT 
face="Times New Roman TUR"><SPAN lang=EN-US>7.<SPAN 
style="FONT: 7pt 'Times New Roman'"><FONT 
size=3>&nbsp;&nbsp;&nbsp;</FONT></SPAN></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">读取<FONT 
face="Times New Roman TUR">8042 Output buffer</FONT>，并保存得到的字节；</SPAN></FONT></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><FONT 
face="Times New Roman TUR"><SPAN lang=EN-US>8.<SPAN 
style="FONT: 7pt 'Times New Roman'"><FONT size=3>&nbsp;&nbsp; 
</FONT></SPAN></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">等待，直到<FONT 
face="Times New Roman TUR">8042&nbsp;Input buffer</FONT>为空为止；</SPAN></FONT></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><FONT 
face="Times New Roman TUR"><SPAN lang=EN-US>9.<SPAN 
style="FONT: 7pt 'Times New Roman'"><FONT size=3>&nbsp;&nbsp; 
</FONT></SPAN></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">发送<FONT 
face="Times New Roman TUR">Write 8042 Output Port</FONT>命令到<FONT 
face="Times New Roman TUR">8042 Input buffer</FONT>；</SPAN></FONT></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><FONT 
face="Times New Roman TUR"><SPAN lang=EN-US>10.<SPAN 
style="FONT: 7pt 'Times New Roman'"><FONT 
size=3>&nbsp;</FONT></SPAN></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">等待，直到<FONT 
face="Times New Roman TUR">8042&nbsp;Input buffer</FONT>为空为止；</SPAN></FONT></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><FONT 
face="Times New Roman TUR"><SPAN lang=EN-US>11.<SPAN 
style="FONT: 7pt 'Times New Roman'"><FONT 
size=3>&nbsp;</FONT></SPAN></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">将从<FONT 
face="Times New Roman TUR">8042 Output Port</FONT>得到的字节的第</SPAN><SPAN 
lang=EN-US>2</SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">位置</SPAN><SPAN 
lang=EN-US>1</SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">（</SPAN><SPAN 
lang=EN-US>OR 2</SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">），然后写入<FONT 
face="Times New Roman TUR">8042 Input buffer</FONT>；</SPAN></FONT></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><FONT 
face="Times New Roman TUR"><SPAN lang=EN-US>12.<SPAN 
style="FONT: 7pt 'Times New Roman'"><FONT size=3> </FONT></SPAN></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">等待，直到<FONT 
face="Times New Roman TUR">8042&nbsp;Input buffer</FONT>为空为止；</SPAN></FONT></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><FONT 
face="Times New Roman TUR"><SPAN lang=EN-US>13.<SPAN 
style="FONT: 7pt 'Times New Roman'"><FONT 
size=3>&nbsp;</FONT></SPAN></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">发送允许键盘操作命令到<FONT 
face="Times New Roman TUR">8042&nbsp;Input buffer</FONT>；</SPAN></FONT></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><FONT 
face="Times New Roman TUR"><SPAN lang=EN-US>14.<SPAN 
style="FONT: 7pt 'Times New Roman'"><FONT size=3>&nbsp; 
</FONT></SPAN></SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">打开中断。</SPAN></FONT></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><FONT 
face="Times New Roman TUR"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"></SPAN></FONT>&nbsp;</P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><FONT 
face="Times New Roman TUR"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">下面代码是一个相关实现：</SPAN></FONT></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System>enable_a20:</FONT></SPAN></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System>&nbsp;&nbsp; sti</FONT></SPAN></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System></FONT></SPAN>&nbsp;</P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System>&nbsp;&nbsp; call&nbsp;&nbsp;&nbsp; 
wait_input_empty</FONT></SPAN></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System>&nbsp;&nbsp; movb $0xAD, %al</FONT></SPAN></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System>&nbsp;&nbsp; outb&nbsp;&nbsp; 
$0x64&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; #disable 
Keyboard</FONT></SPAN></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System></FONT></SPAN>&nbsp;</P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System>&nbsp;&nbsp; call&nbsp;&nbsp;&nbsp; 
wait_input_empty</FONT></SPAN></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System>&nbsp;&nbsp; movb $0xD0, %al</FONT></SPAN></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System>&nbsp;&nbsp; outb&nbsp;&nbsp; 
$0x64&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; # command-read 8042 
output port</FONT></SPAN></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System></FONT></SPAN>&nbsp;</P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System>&nbsp;&nbsp; call&nbsp; &nbsp; wait_output_full</FONT></SPAN></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System>&nbsp;&nbsp; inb&nbsp;&nbsp; 
&nbsp;$0x60&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; # got the 
value of 8042 output port and save it</FONT></SPAN></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System>&nbsp;&nbsp; pushb %al</FONT></SPAN></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System></FONT></SPAN>&nbsp;</P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System>&nbsp;&nbsp; call&nbsp;&nbsp;&nbsp; wait_input_empty&nbsp;&nbsp; 
</FONT></SPAN></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l5 level1 lfo3"><FONT 
face=System>&nbsp;&nbsp; movb $0xD1, %al</FONT></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l5 level1 lfo3"><FONT 
face=System>&nbsp;&nbsp; outb&nbsp;&nbsp; 
$0x64&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; # command-write 8042 
output port</FONT></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l5 level1 lfo3"><FONT 
face=System></FONT>&nbsp;</P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l5 level1 lfo3"><FONT 
face=System>&nbsp;&nbsp; call&nbsp;&nbsp;&nbsp; wait_input_empty</FONT></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l5 level1 lfo3"><FONT 
face=System>&nbsp;&nbsp; popb %al</FONT></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l5 level1 lfo3"><FONT 
face=System>&nbsp;&nbsp; orb&nbsp;&nbsp;&nbsp; $0x02, 
%al&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; # enable A20 Gate&nbsp;</FONT></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l5 level1 lfo3"><FONT 
face=System>&nbsp;&nbsp; outb&nbsp; $0x60</FONT></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l5 level1 lfo3"><FONT 
face=System></FONT>&nbsp;</P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System>&nbsp;&nbsp; call&nbsp;&nbsp;&nbsp; 
wait_input_empty</FONT></SPAN></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System>&nbsp;&nbsp; movb $0xAE, %al</FONT></SPAN></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l2 level1 lfo9"><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><FONT 
face=System>&nbsp;&nbsp; outb&nbsp;&nbsp; 
$0x64&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; #enable 
Keyboard</FONT></SPAN></P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l5 level1 lfo3"><FONT 
face=System></FONT>&nbsp;</P>
<P class=MsoNormal 
style="MARGIN: 0cm 0cm 0pt 21pt; TEXT-INDENT: -21pt; tab-stops: list 21.0pt; mso-list: l5 level1 lfo3"><FONT
1234

⌨️ 快捷键说明

复制代码 Ctrl + C
搜索代码 Ctrl + F
全屏模式 F11
切换主题 Ctrl + Shift + D
显示快捷键 ?
增大字号 Ctrl + =
减小字号 Ctrl + -