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14<h1 align="left">MI_Swap* <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/mi.h&gt;</CODE><BR>
20  <BR>
21  <CODE>u32 MI_SwapWord( u32 setData, volatile u32* destp );</CODE><br>
22  <CODE>u8  MI_SwapByte( u32 setData, volatile u8*  destp );</CODE></dd>
23</dl>
24<h2>Arguments</h2>
25<TABLE border="1" width="100%">
26  <TBODY>
27    <TR>
28      <TD width="13%"><EM><STRONG>setData</STRONG></EM></TD>
29      <TD width="87%">The data that is set</TD>
30    </TR>
31    <TR>
32      <TD width="13%"><EM><STRONG>destp</STRONG></EM></TD>
33      <TD width="87%">Pointer to the swap destination</TD>
34    </TR>
35  </TBODY>
36</TABLE>
37
38<h2>Return Values</h2>
39<p>Value  stored in the swap destination immediately prior to the swap.</p>
40
41<H2>Description</H2>
42<P>This function swaps <CODE><EM><STRONG>setData</STRONG></EM></CODE> and the data stored at *<EM><CODE><STRONG>destp</STRONG></CODE></EM>. This function implements spinlock to exclusively control resources that are shared between processors or modules. <CODE>MI_SwapByte()</CODE> swaps byte data. <CODE>MI_SwapWord()</CODE> swaps word data.</P>
43<P>Note that byte access to the main memory is possible only via cache in the TEG environment. Therefore, <CODE>MI_SwapWord()</CODE> should be used for main memory.</P>
44
45
46<h2>Internal Operation</h2>
47<P>This swaps using the ARM instructions <CODE>swp</CODE> or <CODE>swpb</CODE>.</P>
48
49<h2>See Also</h2>
50<P>None.</P>
51
52<H2>Revision History</H2>
53<P>
542004/10/18 Corrected the description of byte access.<br> 2004/02/10 Initial version.
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56<hr><p>CONFIDENTIAL</p></body>
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