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diff --git a/recipes/i2c/files/Crc8.c b/recipes/i2c/files/Crc8.c
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+++ b/recipes/i2c/files/Crc8.c
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+/****************************************************************************
+*
+*   Copyright (c) 2006 Dave Hylands     <dhylands@gmail.com>
+*
+*   This program is free software; you can redistribute it and/or modify
+*   it under the terms of the GNU General Public License version 2 as
+*   published by the Free Software Foundation.
+*
+*   Alternatively, this software may be distributed under the terms of BSD
+*   license.
+*
+*   See README and COPYING for more details.
+*
+****************************************************************************/
+/**
+*
+*   @file   Crc8.c 
+*
+*   @brief  This file contains the definition of the CRC-8 algorithim
+*           used by SMBus
+*           
+*
+*****************************************************************************/
+
+/* ---- Include Files ----------------------------------------------------- */
+
+#include "Config.h"
+
+#include "Crc8.h"
+
+#include "Log.h"
+
+/* ---- Public Variables -------------------------------------------------- */
+/* ---- Private Constants and Types --------------------------------------- */
+/* ---- Private Variables ------------------------------------------------- */
+/* ---- Private Function Prototypes --------------------------------------- */
+/* ---- Functions --------------------------------------------------------- */
+
+/****************************************************************************/
+/**
+*   Calculates the CRC-8 used as part of SMBus.
+*
+*   CRC-8 is defined to be x^8 + x^2 + x + 1
+*
+*   To use this function use the following template:
+*
+*       crc = Crc8( crc, data );
+*/
+
+#if 0   // Traditional implementation
+
+#define POLYNOMIAL    (0x1070U << 3) 
+
+unsigned char Crc8( unsigned char inCrc, unsigned char inData )
+{
+        int i;
+    unsigned short  data;
+
+    data = inCrc ^ inData;
+    data <<= 8;
+  
+        for ( i = 0; i < 8; i++ ) 
+    {
+                if (( data & 0x8000 ) != 0 )
+        {
+            data = data ^ POLYNOMIAL;
+        }
+                data = data << 1;
+        }
+
+#if 0
+#if defined( LogBuf2 )
+    LogBuf2( "Crc8: data:0x%02x crc:0x%02x\n", inData, (unsigned char)( data >> 8 ));
+#else
+
+    Log( "Crc8: data:0x%02x crc:0x%02x\n", inData, (unsigned char)( data >> 8 ));
+#endif
+
+#endif
+
+
+        return (unsigned char)( data >> 8 );
+
+} // Crc8
+
+#else   // Optimized for 8 bit CPUs (0x22 bytes on ATMega128 versus 0x30 for above version)
+
+unsigned char Crc8( unsigned char inCrc, unsigned char inData )
+{
+        unsigned char   i;
+    unsigned char   data;
+
+    data = inCrc ^ inData;
+  
+        for ( i = 0; i < 8; i++ ) 
+    {
+        if (( data & 0x80 ) != 0 )
+        {
+            data <<= 1;
+            data ^= 0x07;
+        }
+        else
+        {
+            data <<= 1;
+        }
+        }
+
+#if 0
+#if defined( LogBuf2 )
+    LogBuf2( "Crc8: data:0x%02x crc:0x%02x\n", inData, data );
+#else
+
+    Log( "Crc8: data:0x%02x crc:0x%02x\n", inData, data );
+#endif
+
+#endif
+
+
+        return data;
+
+} // Crc8
+
+#endif
+
+
+#if defined( CFG_CRC8BLOCK )
+
+/****************************************************************************/
+/**
+*   Calculates the CRC-8 used as part of SMBus over a block of memory.
+*/
+
+uint8_t Crc8Block( uint8_t crc, uint8_t *data, uint8_t len )
+{
+    while ( len > 0 )
+    {
+        crc = Crc8( crc, *data++ );
+        len--;
+    }
+
+    return crc;
+
+} // Crc8Block
+
+#endif  // CFG_CRC8BLOCK
+
+/** @} */
+
+