1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
2<html>
3
4<head>
5<META http-equiv="Content-Type" content="text/html; charset=windows-1252">
6<META name="GENERATOR" content="IBM WebSphere Studio Homepage Builder Version 7.0.0.0 for Windows">
7<META http-equiv="Content-Style-Type" content="text/css">
8<title>OS_DisableInterrupts</title>
9<LINK rel="stylesheet" href="../../css/nitro.css" type="text/css">
10</head>
11
12<body>
13
14<h1 align="left">OS_DisableInterrupts <img src="../../image/NTR.gif" align="middle"><img src="../../image/TWL.gif" align="middle"></h1>
15<h2>Syntax</h2>
16
17<dl>
18  <dd>
19<CODE>#include &lt;nitro/os.h&gt;</CODE><BR>
20  <BR>
21  <CODE>OSIntrMode OS_DisableInterrupts( void );</CODE></dd>
22</dl><h2>Arguments</h2>
23<P>None.</P>
24<h2>Return Values</h2>
25<p>Returns a value that indicates the state before this function was called.</p>
26<p>The type of the return value is <CODE>OSIntrMode</CODE> (a <CODE>u32</CODE> typedef), but the values that can be returned will be one of the <CODE>OSIntrMode_Irq</CODE> enumerated type values below.<BR>
27</p>
28<TABLE cellspacing="2">
29  <TBODY>
30    <TR>
31      <TH>Value</TH>
32      <TH>Previous state</TH>
33    </TR>
34    <TR>
35      <TD>OS_INTRMODE_IRQ_DISABLE</TD>
36      <TD>IRQ Disable (prohibited)</TD>
37    </TR>
38    <TR>
39      <TD>OS_INTRMODE_IRQ_ENABLE</TD>
40      <TD>IRQ Enable (permitted)</TD>
41    </TR>
42  </TBODY>
43</TABLE>
44<H2>Description</H2>
45<P>This function disables IRQ interrupts.</P>
46<P>The master enable flag for all interrupts (the Interrupt Master Enable Flag) is what is disabled here. If IRQs are disabled with this function, no interrupts will occur even if IRQ interrupt causes are individually set to enable.</P>
47<P>The return value indicates the state prior to calling the function.</P>
48
49<h2>Internal Operation</h2>
50<P>Sets (set is disabled) the CPSR (current program status register) IRQ interrupt control bit.</P>
51
52<h2>See Also</h2>
53<p><CODE><A href="OS_EnableInterrupts.html">OS_EnableInterrupts</A>, <A href="OS_RestoreInterrupts.html">OS_RestoreInterrupts</A><br></CODE></p>
54
55<H2>Revision History</H2>
56<P>
572005/03/08 Standardized the Japanese term for &quot;interrupt.&quot;<BR>2004/03/04 Changed so FIQ is not included in processing.<BR>2004/01/14 Changed so FIQ is included in processing.<BR>2003/12/01 Initial version.</P>
58<hr><p>CONFIDENTIAL</p></body>
59</html>
60