14 //#include "EMCRIOS.h"
17 static BYTE ecctable[256] = {
18 0x00,0x55,0x56,0x03,0x59,0x0C,0x0F,0x5A,0x5A,0x0F,0x0C,0x59,0x03,0x56,0x55,0x00,
19 0x65,0x30,0x33,0x66,0x3C,0x69,0x6A,0x3F,0x3F,0x6A,0x69,0x3C,0x66,0x33,0x30,0x65,
20 0x66,0x33,0x30,0x65,0x3F,0x6A,0x69,0x3C,0x3C,0x69,0x6A,0x3F,0x65,0x30,0x33,0x66,
21 0x03,0x56,0x55,0x00,0x5A,0x0F,0x0C,0x59,0x59,0x0C,0x0F,0x5A,0x00,0x55,0x56,0x03,
22 0x69,0x3C,0x3F,0x6A,0x30,0x65,0x66,0x33,0x33,0x66,0x65,0x30,0x6A,0x3F,0x3C,0x69,
23 0x0C,0x59,0x5A,0x0F,0x55,0x00,0x03,0x56,0x56,0x03,0x00,0x55,0x0F,0x5A,0x59,0x0C,
24 0x0F,0x5A,0x59,0x0C,0x56,0x03,0x00,0x55,0x55,0x00,0x03,0x56,0x0C,0x59,0x5A,0x0F,
25 0x6A,0x3F,0x3C,0x69,0x33,0x66,0x65,0x30,0x30,0x65,0x66,0x33,0x69,0x3C,0x3F,0x6A,
26 0x6A,0x3F,0x3C,0x69,0x33,0x66,0x65,0x30,0x30,0x65,0x66,0x33,0x69,0x3C,0x3F,0x6A,
27 0x0F,0x5A,0x59,0x0C,0x56,0x03,0x00,0x55,0x55,0x00,0x03,0x56,0x0C,0x59,0x5A,0x0F,
28 0x0C,0x59,0x5A,0x0F,0x55,0x00,0x03,0x56,0x56,0x03,0x00,0x55,0x0F,0x5A,0x59,0x0C,
29 0x69,0x3C,0x3F,0x6A,0x30,0x65,0x66,0x33,0x33,0x66,0x65,0x30,0x6A,0x3F,0x3C,0x69,
30 0x03,0x56,0x55,0x00,0x5A,0x0F,0x0C,0x59,0x59,0x0C,0x0F,0x5A,0x00,0x55,0x56,0x03,
31 0x66,0x33,0x30,0x65,0x3F,0x6A,0x69,0x3C,0x3C,0x69,0x6A,0x3F,0x65,0x30,0x33,0x66,
32 0x65,0x30,0x33,0x66,0x3C,0x69,0x6A,0x3F,0x3F,0x6A,0x69,0x3C,0x66,0x33,0x30,0x65,
33 0x00,0x55,0x56,0x03,0x59,0x0C,0x0F,0x5A,0x5A,0x0F,0x0C,0x59,0x03,0x56,0x55,0x00
36 static void trans_result (BYTE, BYTE, BYTE *, BYTE *);
47 #define BIT23 0x00800000L
49 #define CORRECTABLE 0x00555554L
51 static void trans_result(reg2,reg3,ecc1,ecc2)
52 BYTE reg2; // LP14,LP12,LP10,...
53 BYTE reg3; // LP15,LP13,LP11,...
54 BYTE *ecc1; // LP15,LP14,LP13,...
55 BYTE *ecc2; // LP07,LP06,LP05,...
57 BYTE a; // Working for reg2,reg3
58 BYTE b; // Working for ecc1,ecc2
59 BYTE i; // For counting
61 a=BIT7; b=BIT7; // 80h=10000000b
62 *ecc1=*ecc2=0; // Clear ecc1,ecc2
65 *ecc1|=b; // LP15,13,11,9 -> ecc1
66 b=b>>1; // Right shift
68 *ecc1|=b; // LP14,12,10,8 -> ecc1
69 b=b>>1; // Right shift
70 a=a>>1; // Right shift
73 b=BIT7; // 80h=10000000b
76 *ecc2|=b; // LP7,5,3,1 -> ecc2
77 b=b>>1; // Right shift
79 *ecc2|=b; // LP6,4,2,0 -> ecc2
80 b=b>>1; // Right shift
81 a=a>>1; // Right shift
85 //static void calculate_ecc(table,data,ecc1,ecc2,ecc3)
86 void calculate_ecc(table,data,ecc1,ecc2,ecc3)
87 BYTE *table; // CP0-CP5 code table
89 BYTE *ecc1; // LP15,LP14,LP13,...
90 BYTE *ecc2; // LP07,LP06,LP05,...
91 BYTE *ecc3; // CP5,CP4,CP3,...,"1","1"
93 DWORD i; // For counting
94 BYTE a; // Working for table
95 BYTE reg1; // D-all,CP5,CP4,CP3,...
96 BYTE reg2; // LP14,LP12,L10,...
97 BYTE reg3; // LP15,LP13,L11,...
99 reg1=reg2=reg3=0; // Clear parameter
100 for(i=0; i<256; ++i) {
101 a=table[data[i]]; // Get CP0-CP5 code from table
102 reg1^=(a&MASK_CPS); // XOR with a
104 { // If D_all(all bit XOR) = 1
105 reg3^=(BYTE)i; // XOR with counter
106 reg2^=~((BYTE)i); // XOR with inv. of counter
110 // Trans LP14,12,10,... & LP15,13,11,... -> LP15,14,13,... & LP7,6,5,..
111 trans_result(reg2,reg3,ecc1,ecc2);
112 *ecc1=~(*ecc1); *ecc2=~(*ecc2); // Inv. ecc2 & ecc3
113 *ecc3=((~reg1)<<2)|BIT1BIT0; // Make TEL format
116 BYTE correct_data(data,eccdata,ecc1,ecc2,ecc3)
118 BYTE *eccdata; // ECC DATA
119 BYTE ecc1; // LP15,LP14,LP13,...
120 BYTE ecc2; // LP07,LP06,LP05,...
121 BYTE ecc3; // CP5,CP4,CP3,...,"1","1"
123 DWORD l; // Working to check d
124 DWORD d; // Result of comparison
125 DWORD i; // For counting
126 BYTE d1,d2,d3; // Result of comparison
127 BYTE a; // Working for add
128 BYTE add; // Byte address of cor. DATA
129 BYTE b; // Working for bit
130 BYTE bit; // Bit address of cor. DATA
132 d1=ecc1^eccdata[1]; d2=ecc2^eccdata[0]; // Compare LP's
133 d3=ecc3^eccdata[2]; // Comapre CP's
134 d=((DWORD)d1<<16) // Result of comparison
138 if (d==0) return(0); // If No error, return
140 if (((d^(d>>1))&CORRECTABLE)==CORRECTABLE)
143 add=0; // Clear parameter
146 for(i=0; i<8; ++i) { // Checking 8 bit
147 if ((d&l)!=0) add|=a; // Make byte address from LP's
148 l>>=2; a>>=1; // Right Shift
151 bit=0; // Clear parameter
153 for(i=0; i<3; ++i) { // Checking 3 bit
154 if ((d&l)!=0) bit|=b; // Make bit address from CP's
155 l>>=2; b>>=1; // Right shift
159 data[add]^=(b<<bit); // Put corrected data
164 d&=0x00ffffffL; // Masking
166 while(d) { // If d=0 finish counting
167 if (d&BIT0) ++i; // Count number of 1 bit
168 d>>=1; // Right shift
173 eccdata[1]=ecc1; eccdata[0]=ecc2; // Put right ECC code
177 return(3); // Uncorrectable error
180 int _Correct_D_SwECC(buf,redundant_ecc,calculate_ecc)
187 err=correct_data(buf,redundant_ecc,*(calculate_ecc+1),*(calculate_ecc),*(calculate_ecc+2));
188 if (err==1) StringCopy(calculate_ecc,redundant_ecc,3);
189 if (err==0 || err==1 || err==2)
194 void _Calculate_D_SwECC(buf,ecc)
198 calculate_ecc(ecctable,buf,ecc+1,ecc+0,ecc+2);