24 lines
1.8 KiB
HTML
24 lines
1.8 KiB
HTML
<html><!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
|
|
<html>
|
|
|
|
<head>
|
|
<title>80386 Programmer's Reference Manual -- Section 9.3</title>
|
|
</head>
|
|
|
|
<body>
|
|
<b>up:</b> <a href="C09.HTM" tppabs="http://webster.cs.ucr.edu/Page_TechDocs/Doc386/C09.HTM">Chapter 9 -- Exceptions and Interrupts</a><br>
|
|
<b>prev:</b> <a href="S09_02.HTM" tppabs="http://webster.cs.ucr.edu/Page_TechDocs/Doc386/S09_02.HTM">9.2 Enabling and Disabling Interrupts</a><br>
|
|
<b>next:</b> <a href="S09_04.HTM" tppabs="http://webster.cs.ucr.edu/Page_TechDocs/Doc386/S09_04.HTM">9.4 Interrupt Descriptor Table</a>
|
|
<p>
|
|
<hr>
|
|
<p>
|
|
<h1>9.3 Priority Among Simultaneous Interrupts and Exceptions</h1>
|
|
If more than one interrupt or exception is pending at an instruction boundary, the processor services one of them at a time. The priority among classes of interrupt and exception sources is shown in <a href="S09_04.HTM#Table 9-2" tppabs="http://webster.cs.ucr.edu/Page_TechDocs/Doc386/S09_04.HTM#Table 9-2">Table 9-2</a>. The processor first services a pending interrupt or exception from the class that has the highest priority, transferring control to the first instruction of the interrupt handler. Lower priority exceptions are discarded; lower priority interrupts are held pending. Discarded exceptions will be rediscovered when the interrupt handler returns control to the point of interruption.
|
|
<p>
|
|
<hr>
|
|
<p><b>up:</b> <a href="C09.HTM" tppabs="http://webster.cs.ucr.edu/Page_TechDocs/Doc386/C09.HTM">Chapter 9 -- Exceptions and Interrupts</a><br>
|
|
<b>prev:</b> <a href="S09_02.HTM" tppabs="http://webster.cs.ucr.edu/Page_TechDocs/Doc386/S09_02.HTM">9.2 Enabling and Disabling Interrupts</a><br>
|
|
<b>next:</b> <a href="S09_04.HTM" tppabs="http://webster.cs.ucr.edu/Page_TechDocs/Doc386/S09_04.HTM">9.4 Interrupt Descriptor Table</a>
|
|
</body>
|
|
|