Diff: crc8.c

Revision:

3:aaa92c61931a

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/crc8.c	Mon Jul 13 13:14:34 2015 +0000
@@ -0,0 +1,99 @@
+//================ File Despciption =========================================//
+//=== File name : crc8.c
+//=== 
+//#include "crc8.h"
+//===========================================================================//
+
+//================ Index ====================================================//
+//
+//================ Include Header ===========================================//
+//
+//================ PUBLIC METHOD ============================================//
+// extern function from another file
+//
+//================ PRIVATE METHOD ===========================================//
+// non extern function
+//
+//================ PUBLIC DATA ==============================================//
+// extern data
+//
+//================ PRIVATE DATA =============================================//
+// non extern data
+//
+//================ PRIVATE DEFINE ===========================================//
+//
+//================ PRIVATE MACRO ============================================//
+//
+//================ SOURCE CODE ==============================================//
+//
+   	//This procedure calculates the cumulative Dallas Semiconductor
+// 1-Wire CRC of all bytes passed to it. The result
+//accumulates in the global variable CRC.
+const unsigned char crc8_table[256]={
+0x00,0x07,0x0E,0x09,0x1C,0x1B,0x12,0x15,0x38,0x3F,0x36,0x31,0x24,0x23,0x2A,0x2D,
+0x70,0x77,0x7E,0x79,0x6C,0x6B,0x62,0x65,0x48,0x4F,0x46,0x41,0x54,0x53,0x5A,0x5D,
+0xE0,0xE7,0xEE,0xE9,0xFC,0xFB,0xF2,0xF5,0xD8,0xDF,0xD6,0xD1,0xC4,0xC3,0xCA,0xCB,
+0x90,0x97,0x9E,0x99,0x8C,0x8B,0x82,0x85,0xA8,0xAF,0xA6,0xA1,0xB4,0xB3,0xBA,0xBD,
+0xC7,0xC0,0xC9,0xCE,0xDB,0xDC,0xD5,0xD2,0xFF,0xF8,0xF1,0xF6,0xE3,0xE4,0xED,0xEA,
+0xB7,0xB0,0xB9,0xBE,0xAB,0xAC,0xA5,0xA2,0x8F,0x88,0x81,0x86,0x93,0x94,0x9D,0x9A,
+0x27,0x20,0x29,0x2E,0x3B,0x3C,0x35,0x32,0x1F,0x18,0x11,0x16,0x03,0x04,0x0D,0x0A,
+0x57,0x50,0x59,0x5E,0x4B,0x4C,0x45,0x42,0x6F,0x68,0x61,0x66,0x73,0x74,0x7D,0x7A,
+0x89,0x8E,0x87,0x80,0x95,0x92,0x9B,0x9C,0xB1,0xB6,0xBF,0xB8,0xAD,0xAA,0xA3,0xA4,
+0xF9,0xFE,0xF7,0xF0,0xE5,0xE2,0xEB,0xEC,0xC1,0xC6,0xCF,0xC8,0xDD,0xDA,0xD3,0xD4,
+0x69,0x6E,0x67,0x60,0x75,0x72,0x7B,0x7C,0x51,0x56,0x5F,0x58,0x4D,0x4A,0x43,0x44,
+0x19,0x1E,0x17,0x10,0x05,0x02,0x0B,0x0C,0x21,0x26,0x2F,0x28,0x3D,0x3A,0x33,0x34,
+0x4E,0x49,0x40,0x47,0x52,0x55,0x5C,0x5B,0x76,0x71,0x78,0x7F,0x6A,0x6D,0x64,0x63,
+0x3E,0x39,0x30,0x37,0x22,0x25,0x2C,0x2B,0x06,0x01,0x08,0x0F,0x1A,0x1D,0x14,0x13,
+0xAE,0xA9,0xA0,0xA7,0xB2,0xB5,0xBC,0xBB,0x96,0x91,0x98,0x9F,0x8A,0x8D,0x84,0x83,
+0xDE,0xD9,0xD0,0xD7,0xC2,0xC5,0xCC,0xCB,0xE6,0xE1,0xE8,0xEF,0xFA,0xFD,0xF4,0xF3
+
+};
+
+
+inline unsigned char crc8Compute(unsigned char *p,unsigned char length)   
+{   
+    unsigned char crc8;   
+    unsigned char i;   
+    unsigned char offset;   
+   
+    crc8 = 0;   
+    for(i = 0; i < length; i++)   
+    {   
+        offset = crc8 ^ *(p + i);   
+        crc8 = crc8_table[offset];   
+    }   
+    return crc8;
+    //return crc8 ^ 0x55;   
+}   
+/*
+* Function: Do_CRC8
+* * Description:
+* Computes the CRC value given the byte and the old CRC value as a static value
+*
+* Return Value: CRC value
+* Parameters: Input data byte to be CRC'ed
+* Remarks:
+* uses a table driven method to speed things up.
+*
+* */
+inline unsigned char crc8OneByte(unsigned char xx,unsigned char ucCRC)
+{
+	ucCRC = crc8_table[ucCRC ^ xx];
+
+	return (ucCRC);
+}
+
+unsigned char Crc8(unsigned char* xx,const int size, unsigned char ucCRC)
+{
+
+	int i;
+	for(i=0; i<size; i++)
+	{
+		ucCRC=crc8OneByte(xx[i],ucCRC);
+	}
+	return ucCRC;
+}
+//================ END OF FILE ==============================================//
+//
+
+