URL
https://opencores.org/ocsvn/mmcfpgaconfig/mmcfpgaconfig/trunk
Subversion Repositories mmcfpgaconfig
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- This comparison shows the changes necessary to convert path
/
- from Rev 4 to Rev 5
- ↔ Reverse comparison
Rev 4 → Rev 5
/trunk/sw/mmc_crc7.cpp
0,0 → 1,119
// |
// MMC Card CRC7 calculator and checker |
// www.openchip.org |
// |
// |
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#include <iostream> |
#include <stdio.h> |
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using namespace std; |
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char crc7[8]; |
char cmd[49]; |
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void do_crc7(char c) { |
char c3; |
char c0; |
// last stage and input bit |
c0 = (crc7[6] == c) ? '0' : '1'; |
// |
c3 = (crc7[2] == c0) ? '0' : '1'; |
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// shift register |
crc7[6] = crc7[5]; |
crc7[5] = crc7[4]; |
crc7[4] = crc7[3]; |
crc7[3] = c3; |
crc7[2] = crc7[1]; |
crc7[1] = crc7[0]; |
crc7[0] = c0; |
} |
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/* |
CMD17 Argument=0x00000100 CRC7=0x43 OK, checked! |
CMD17 Argument=0x00004000 CRC7=0x8F OK, checked! |
*/ |
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void calc_crc(int command, unsigned int arg) { |
int i; |
unsigned int mask; |
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// fill CMD |
mask = 1; |
for (i=0;i<6;i++) { |
if (mask & command) { |
cmd[7-i] = '1'; |
} else { |
cmd[7-i]='0'; |
} |
mask <<= 1; |
} |
// fill ARG |
mask = 1; |
for (i=0;i<32;i++) { |
if (mask & arg) { |
cmd[39-i] = '1'; |
} else { |
cmd[39-i]='0'; |
} |
mask <<= 1; |
} |
// clear CRC |
for (i=0;i<7;i++) crc7[i] = '0'; |
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// calc CRC |
for (i=0;i<40;i++) do_crc7(cmd[i]); |
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// copy CRC |
cmd[40] = crc7[6]; |
cmd[41] = crc7[5]; |
cmd[42] = crc7[4]; |
cmd[43] = crc7[3]; |
cmd[44] = crc7[2]; |
cmd[45] = crc7[1]; |
cmd[46] = crc7[0]; |
} |
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int main (int argc, char *argv[]) |
{ |
char quit; |
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int i; |
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// clear CRC |
crc7[7] = 0; |
for (i=0;i<7;i++) crc7[i] = '0'; |
// clear CMD, ARG |
cmd[48] = 0; |
for (i=0;i<48;i++) cmd[i] = '0'; |
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cmd[1] = '1'; // Start bit |
cmd[47] = '1'; // Stop Bit |
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// check CRC calculation |
calc_crc(0,0); printf("\n\rTest CMD0 ,0x0 %s", cmd); |
calc_crc(17,0x100); printf("\n\rTest CMD17,0x0100 %s", cmd); |
calc_crc(17,0x4000); printf("\n\rTest CMD17,0x04000 %s", cmd); |
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printf("\n\rCalc CRCs"); |
calc_crc(0,0); printf("\n\rTest CMD0 ,0x0 %s", cmd); |
calc_crc(1,0x80FF8000); printf("\n\rTest CMD1 ,0x80FF8000 %s", cmd); |
calc_crc(2,0); printf("\n\rTest CMD2 ,0x0 %s", cmd); |
calc_crc(3,0x10000); printf("\n\rTest CMD3 ,0x10000 %s", cmd); |
calc_crc(7,0x10000); printf("\n\rTest CMD7 ,0x10000 %s", cmd); |
calc_crc(11,0x0000); printf("\n\rTest CMD11,0x00000 %s", cmd); |
calc_crc(55,0x0000); printf("\n\rTest CMD55,0x00000 %s", cmd); |
calc_crc(41,0x80FF8000); printf("\n\rTest ACMD41,0x80FF8000 %s", cmd); |
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cin >>quit; |
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return 0; |
} |
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