📄 os20rto8.htm
字号:
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<meta name="GENERATOR" content="Quadralay WebWorks Publisher Professional Edition 6.0.5">
<meta name="TEMPLATEBASE" content="book_html">
<meta name="LASTUPDATED" content="12/04/03 16:06:08">
<title>11.2.5 Making task awareness available </title>
<STYLE TYPE="text/css">
<!--
span.Signal { text-transform: uppercase; font-family: Verdana }
-->
</STYLE>
</head>
<body link="#3366CC" vlink="#9999CC" text="#000000" alink="#0000CC" bgcolor="#FFFFFF"
background="images/backgrnd.gif">
<p><img src="images/stlogo.gif" width="106" height="83" align="left"
alt="logo here!"> </p>
<table width="331" border="0" align="right" cellpadding="0" cellspacing="0">
<tr>
<td><a href="a_refman.htm"><img src="images/navtoc.gif" width="84" height="23"
border="0" alt="TOC"> </a></td>
<td><a href="os20rto7.htm"><img src="images/navprev.gif" width="80" height="23"
border="0" alt="PREV"> </a></td>
<td><a href="os20rto9.htm"><img src="images/navnext.gif" width="83" height="23"
border="0" alt="NEXT"> </a></td>
<td><a href="a_refmaa.htm"><img src="images/navidx.gif" width="84" height="23"
border="0" alt="INDEX"> </a></td>
</tr>
</table>
<p><br clear="all">
</p>
<hr align="left">
<blockquote>
<h3>
<a name="1204514"> </a><font color="#003366" face="Verdana, Arial, Helvetica, sans-serif">11.2.5 Making task awareness available</font>
</h3>
<p>
<a name="1204518"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">In order to determine what was happening on the target, the OS20 task awareness code in <strong>st20run</strong> needs to read some of the OS20 data structures from the target memory, and some additional hardware registers.</font>
</p>
<p>
<a name="1204522"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">To make this possible three conditions must be met.</font>
</p>
<ul>
<p> <font size=2 face="Verdana, Arial, Helvetica, sans-serif"><li ><a name="1204523"> </a><strong>st20run</strong> must have the correct symbol table available for the program which is being debugged. This means that the debug data files (<font size=2 face=Courier><strong>.dbg</strong></font> files) for the application must be present in the directory from which <strong>st20run</strong> was started, or specified later using the <font size=2 face=Courier><strong>program</strong></font> command.</font></p>
<p> <font size=2 face="Verdana, Arial, Helvetica, sans-serif"><li ><a name="1204527"> </a>All memory which holds OS20 data structures must be readable by <strong>st20run</strong>. In particular, any internal memory segments which hold key data structures, and also a memory segment which describes the interrupt controller's registers, must exist. Normally these are set up automatically if the <font size=2 face=Courier><strong>chip</strong></font> command has been used, otherwise the segments must be specified in the user's <font size=2 face=Courier><strong>.cfg</strong></font> files, for example:</font></p>
<dl>
<dt> <a name="1204528"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><font size=2 face=Courier><strong>memory INTERNAL 0x80000000 0x1000 RAM</strong></font></font>
<dt> <a name="1204529"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><font size=2 face=Courier><strong>memory INT_CONTROLLER 0x20000000 0x1000 PERIPHERAL</strong></font></font>
</dl>
<p> <font size=2 face="Verdana, Arial, Helvetica, sans-serif"><li ><a name="1204533"> </a>The programmer must be careful to avoid corrupting OS20 data structures. In particular when an object (for example a <font size=2 face=Courier><strong>semaphore_t</strong></font>) is no longer required, it should be deleted, and not simply be allowed to go out of scope. While this would not normally affect the running of the program, it can cause the debugger to display incorrect information, which could be misleading when trying to track down a problem (see <a href="os20rto9.htm#1204538"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>Section⌨️ 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 + -