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14<h1 align="left">MICSamplingRate <img src="../../image/NTR.gif"><img src="../../image/TWL.gif"></h1>
15
16<h2>Definition</h2>
17
18<dl>
19  <dd>
20<CODE>#include &lt;nitro/spi.h&gt;</CODE><BR>
21  <PRE><CODE>typedef enum
22{
23	MIC_SAMPLING_RATE_8K	= ( HW_CPU_CLOCK_ARM7 /  8000 ) ,
24	MIC_SAMPLING_RATE_11K	= ( HW_CPU_CLOCK_ARM7 / 11025 ) ,
25	MIC_SAMPLING_RATE_16K	= ( HW_CPU_CLOCK_ARM7 / 16000 ) ,
26	MIC_SAMPLING_RATE_22K	= ( HW_CPU_CLOCK_ARM7 / 22050 ) ,
27	MIC_SAMPLING_RATE_32K	= ( HW_CPU_CLOCK_ARM7 / 32000 )
28	MIC_SAMPLING_RATE_LIMIT	= 1024
29
30} MICSamplingRate;</CODE></PRE>
31  </dd>
32
33</dl><h2>Elements</h2>
34<TABLE border="1" width="100%">
35  <TBODY>
36    <TR>
37      <TD width="300"><em><strong><font face="Courier New">MIC_SAMPLING_RATE_8K</font></strong></em></TD>
38      <TD width="700">8 kHz</TD>
39    </TR>
40    <TR>
41      <TD width="300"><em><strong><font face="Courier New">MIC_SAMPLING_RATE_11K</font></strong></em></TD>
42      <TD width="700">11.025 kHz</TD>
43    </TR>
44    <TR>
45      <TD width="300"><em><strong><font face="Courier New">MIC_SAMPLING_RATE_16K</font></strong></em></TD>
46      <TD width="700">16 kHz</TD>
47    </TR>
48    <TR>
49      <TD width="300"><em><strong><font face="Courier New">MIC_SAMPLING_RATE_22K</font></strong></em></TD>
50      <TD width="700">22.05 kHz</TD>
51    </TR>
52    <TR>
53      <TD width="300"><em><strong><font face="Courier New">MIC_SAMPLING_RATE_32K</font></strong></em></TD>
54      <TD width="700">32 kHz</TD>
55    </TR>
56    <TR>
57      <TD width="300"><em><strong><font face="Courier New">MIC_SAMPLING_RATE_LIMIT</font></strong></em></TD>
58      <TD width="700">The shortest sampling rate that is supported.</TD>
59    </TR>
60  </TBODY>
61</TABLE>
62
63<H2>Description</H2>
64<P>This is a list of the sampling rates.<br>These values define typical sampling rates that are converted into ARM7 timer cycles.</P>
65
66<H2>Note</H2>
67<P><FONT color=red>The ARM7 can support sampling rates up to <em><strong><font  face="Courier New">MIC_SAMPLING_RATE_LIMIT</font></strong></em> when devoted to microphone sampling,  but we cannot guarantee this when the ARM7 is also being used for sounds and other features. Please specify  an appropriate rate, keeping in mind the load placed on the ARM7.<br>The ARM7 timer is set in units of CPU clock ticks, so appreciate that error is built into the defined frequencies.</FONT></P>
68
69<h2>See Also</h2>
70<P><code><a href="MIC_StartAutoSampling.html">MIC_StartAutoSampling</a>, <a  href="MIC_StartAutoSamplingAsync.html">MIC_StartAutoSamplingAsync</a></code></P>
71
72<H2>Revision History</H2>
73<P>2004/06/01 Initial version.</P>
74<hr><p>CONFIDENTIAL</p></body>
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