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14<h1 align="left">AIRegisterDMACallback</h1>
15
16<h2>Syntax</h2>
17<dl><dd><pre class="construction">
18#include &lt;revolution/ai.h&gt;
19
20typedef void (*AIDCallback)(void);
21
22AIDCallback AIRegisterDMACallback(AIDCallback callback);
23</pre></dd></dl>
24
25<h2>Arguments</h2>
26<TABLE class="arguments" border="1" >
27  <tr>
28<th>callback</th>
29<td>Callback function for the AI DMA interrupt (<code>AIDINT</code>).</td>
30  </tr>
31</table>
32
33<h2>Return Values</h2>
34<p>Returns a pointer to the old callback function already registered. Returns <code>NULL</code> if no callback function has been registered.</p>
35
36<h2>Description</h2>
37<p>The <code>AIRegisterDMACallback</code> function registers the callback function to be invoked for the AI-DMA interrupt (<code>AIDINT</code>). The existing callback function is replaced by the new callback function unconditionally. The callback function is deleted if <code>NULL</code> is specified for an argument and no callback function will ever be called in response to an AI DMA interrupt.</p>
38
39<p><B>Note: The AX library calls this function from inside the initialization function (for example, from inside <code>AXInit</code>). Because of this, any AI DMA interrupt callback set using this function before the AX library initialization function was called will be overwritten by the AX callback. If you are using an original AI DMA interrupt callback, be sure to set it using this function only after calling the AX library initialization function.</B></p>
40
41<h2>See Also</h2>
42<P class="reference">
43<a href="../../ax/Initialization/AXInit.html">AXInit</a>
44</P>
45
46<H2>Revision History</H2>
47<P>
482008/12/26 Added a note about the AI DMA interrupt callback.<br>2006/03/01 Initial version.<BR>
49</P>
50
51<hr><p>CONFIDENTIAL</p></body>
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