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14<h1 align="left">MATH_CalcCRC* <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  <PRE><CODE>#include &lt;nitro/math/crc.h&gt;
20
21u8  MATH_CalcCRC8( const <A href="MATHCRCTable.html">MATHCRC8Table</A> *table, const void* data, u32 dataLength );
22u16 MATH_CalcCRC16( const <A href="MATHCRCTable.html">MATHCRC16Table</A> *table, const void* data, u32 dataLength );
23u16 MATH_CalcCRC16CCITT( const <A href="MATHCRCTable.html">MATHCRC16Table</A> *table, const void* data, u32 dataLength );
24u32 MATH_CalcCRC32( const <A href="MATHCRCTable.html">MATHCRC32Table</A> *table, const void* data, u32 dataLength );
25u32 MATH_CalcCRC32POSIX( const <A href="MATHCRCTable.html">MATHCRC32Table</A> *table, const void* data, u32 dataLength );
26</CODE></PRE>
27  </dd>
28</dl><h2>Arguments</h2>
29
30<table border="1" width="100%">
31    <TR>
32      <TD width="176"><em><strong><font face="Courier New">table</font></strong></em></TD>
33      <TD width="670">Pointer to the tables used to compute CRCs.</TD>
34    </TR>
35    <TR>
36      <TD width="176"><em><strong><font face="Courier New">data</font></strong></em></TD>
37      <TD width="670">Pointer to the input data.</TD>
38    </TR>
39    <TR>
40      <TD width="176"><em><strong><font face="Courier New">dataLength</font></strong></em></TD>
41      <TD width="670">Size of the input data.</TD>
42    </TR>
43  </table>
44<h2>Return Values</h2>
45<p>Various CRC values</p>
46<H2>Description</H2>
47<P>Performs various CRC computations in one call. You must initialize the <CODE>table</CODE> argument by calling a <CODE><A href="MATH_CRCInitTable.html">MATH_CRC*InitTable</A></CODE> function in advance.<BR>Any size and alignment position can be used for the input data.<BR> CRC-8 is an algorithm that finds an 8-bit hash value.<BR> CRC-16 and CRC-16/CCITT are algorithms that find 16-bit hash values.<BR> CRC-32 and CRC-32/POSIX are algorithms that find 32-bit hash values. CRC-16 is the algorithm used in the ARC and LHA compression programs. One restriction is that the hash value does not change when a <code>0</code> byte is appended to the top. CRC-16/CCITT is an algorithm that is used in many data link layer standards as a FCS (Frame Check Sequence). It is defined in the x.25 standard of the CCITT (Comite Consultatif International Telegraphique et Telephonique). CRC-32 is an algorithm used in compression programs, such as PKZIP, and image formats, such as PNG. For details, see ISO 3309 and RFC 2083. CRC-32/POSIX is an algorithm used in the cksum command, which is included in POSIX-compliant Unix. It is defined in POSIX 1003.2. With the <code>cksum</code> command, CRC is taken after the file length is appended to the end of the input file.
48</P>
49<h2>See Also</h2>
50<P><a href="MATH_CRCInitTable.html"><code>MATH_CRC*InitTable</code></a>, <a href="MATH_CRCInit.html"><code>MATH_CRC*Init</code></a>, <a href="MATH_CRCUpdate.html"><code>MATH_CRC*Update</code></a>, <a href="MATH_CRCGetHash.html"><code>MATH_CRC*GetHash</code></a></P>
51<H2>Revision History</H2>
52<P>
532005/04/12 Initial version.
54</P>
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