#ifndef HAMMING_H #define HAMMING_H // Hamming 8/4 decoding table // decoded_value = hamming_8_4_decode[encoded_value] // 0xff - double bit error that can't be corrected const unsigned char hamming_8_4_decode[256] = { 0x01, 0xff, 0x01, 0x01, 0xff, 0x00, 0x01, 0xff, 0xff, 0x02, 0x01, 0xff, 0x0a, 0xff, 0xff, 0x07, 0xff, 0x00, 0x01, 0xff, 0x00, 0x00, 0xff, 0x00, 0x06, 0xff, 0xff, 0x0b, 0xff, 0x00, 0x03, 0xff, 0xff, 0x0c, 0x01, 0xff, 0x04, 0xff, 0xff, 0x07, 0x06, 0xff, 0xff, 0x07, 0xff, 0x07, 0x07, 0x07, 0x06, 0xff, 0xff, 0x05, 0xff, 0x00, 0x0d, 0xff, 0x06, 0x06, 0x06, 0xff, 0x06, 0xff, 0xff, 0x07, 0xff, 0x02, 0x01, 0xff, 0x04, 0xff, 0xff, 0x09, 0x02, 0x02, 0xff, 0x02, 0xff, 0x02, 0x03, 0xff, 0x08, 0xff, 0xff, 0x05, 0xff, 0x00, 0x03, 0xff, 0xff, 0x02, 0x03, 0xff, 0x03, 0xff, 0x03, 0x03, 0x04, 0xff, 0xff, 0x05, 0x04, 0x04, 0x04, 0xff, 0xff, 0x02, 0x0f, 0xff, 0x04, 0xff, 0xff, 0x07, 0xff, 0x05, 0x05, 0x05, 0x04, 0xff, 0xff, 0x05, 0x06, 0xff, 0xff, 0x05, 0xff, 0x0e, 0x03, 0xff, 0xff, 0x0c, 0x01, 0xff, 0x0a, 0xff, 0xff, 0x09, 0x0a, 0xff, 0xff, 0x0b, 0x0a, 0x0a, 0x0a, 0xff, 0x08, 0xff, 0xff, 0x0b, 0xff, 0x00, 0x0d, 0xff, 0xff, 0x0b, 0x0b, 0x0b, 0x0a, 0xff, 0xff, 0x0b, 0x0c, 0x0c, 0xff, 0x0c, 0xff, 0x0c, 0x0d, 0xff, 0xff, 0x0c, 0x0f, 0xff, 0x0a, 0xff, 0xff, 0x07, 0xff, 0x0c, 0x0d, 0xff, 0x0d, 0xff, 0x0d, 0x0d, 0x06, 0xff, 0xff, 0x0b, 0xff, 0x0e, 0x0d, 0xff, 0x08, 0xff, 0xff, 0x09, 0xff, 0x09, 0x09, 0x09, 0xff, 0x02, 0x0f, 0xff, 0x0a, 0xff, 0xff, 0x09, 0x08, 0x08, 0x08, 0xff, 0x08, 0xff, 0xff, 0x09, 0x08, 0xff, 0xff, 0x0b, 0xff, 0x0e, 0x03, 0xff, 0xff, 0x0c, 0x0f, 0xff, 0x04, 0xff, 0xff, 0x09, 0x0f, 0xff, 0x0f, 0x0f, 0xff, 0x0e, 0x0f, 0xff, 0x08, 0xff, 0xff, 0x05, 0xff, 0x0e, 0x0d, 0xff, 0xff, 0x0e, 0x0f, 0xff, 0x0e, 0x0e, 0xff, 0x0e }; const unsigned char hamming_24_18_parities[3][256] = { { // Parities of first byte 0x00, 0x21, 0x22, 0x03, 0x23, 0x02, 0x01, 0x20, 0x24, 0x05, 0x06, 0x27, 0x07, 0x26, 0x25, 0x04, 0x25, 0x04, 0x07, 0x26, 0x06, 0x27, 0x24, 0x05, 0x01, 0x20, 0x23, 0x02, 0x22, 0x03, 0x00, 0x21, 0x26, 0x07, 0x04, 0x25, 0x05, 0x24, 0x27, 0x06, 0x02, 0x23, 0x20, 0x01, 0x21, 0x00, 0x03, 0x22, 0x03, 0x22, 0x21, 0x00, 0x20, 0x01, 0x02, 0x23, 0x27, 0x06, 0x05, 0x24, 0x04, 0x25, 0x26, 0x07, 0x27, 0x06, 0x05, 0x24, 0x04, 0x25, 0x26, 0x07, 0x03, 0x22, 0x21, 0x00, 0x20, 0x01, 0x02, 0x23, 0x02, 0x23, 0x20, 0x01, 0x21, 0x00, 0x03, 0x22, 0x26, 0x07, 0x04, 0x25, 0x05, 0x24, 0x27, 0x06, 0x01, 0x20, 0x23, 0x02, 0x22, 0x03, 0x00, 0x21, 0x25, 0x04, 0x07, 0x26, 0x06, 0x27, 0x24, 0x05, 0x24, 0x05, 0x06, 0x27, 0x07, 0x26, 0x25, 0x04, 0x00, 0x21, 0x22, 0x03, 0x23, 0x02, 0x01, 0x20, 0x28, 0x09, 0x0a, 0x2b, 0x0b, 0x2a, 0x29, 0x08, 0x0c, 0x2d, 0x2e, 0x0f, 0x2f, 0x0e, 0x0d, 0x2c, 0x0d, 0x2c, 0x2f, 0x0e, 0x2e, 0x0f, 0x0c, 0x2d, 0x29, 0x08, 0x0b, 0x2a, 0x0a, 0x2b, 0x28, 0x09, 0x0e, 0x2f, 0x2c, 0x0d, 0x2d, 0x0c, 0x0f, 0x2e, 0x2a, 0x0b, 0x08, 0x29, 0x09, 0x28, 0x2b, 0x0a, 0x2b, 0x0a, 0x09, 0x28, 0x08, 0x29, 0x2a, 0x0b, 0x0f, 0x2e, 0x2d, 0x0c, 0x2c, 0x0d, 0x0e, 0x2f, 0x0f, 0x2e, 0x2d, 0x0c, 0x2c, 0x0d, 0x0e, 0x2f, 0x2b, 0x0a, 0x09, 0x28, 0x08, 0x29, 0x2a, 0x0b, 0x2a, 0x0b, 0x08, 0x29, 0x09, 0x28, 0x2b, 0x0a, 0x0e, 0x2f, 0x2c, 0x0d, 0x2d, 0x0c, 0x0f, 0x2e, 0x29, 0x08, 0x0b, 0x2a, 0x0a, 0x2b, 0x28, 0x09, 0x0d, 0x2c, 0x2f, 0x0e, 0x2e, 0x0f, 0x0c, 0x2d, 0x0c, 0x2d, 0x2e, 0x0f, 0x2f, 0x0e, 0x0d, 0x2c, 0x28, 0x09, 0x0a, 0x2b, 0x0b, 0x2a, 0x29, 0x08 }, { // Parities of second byte 0x00, 0x29, 0x2a, 0x03, 0x2b, 0x02, 0x01, 0x28, 0x2c, 0x05, 0x06, 0x2f, 0x07, 0x2e, 0x2d, 0x04, 0x2d, 0x04, 0x07, 0x2e, 0x06, 0x2f, 0x2c, 0x05, 0x01, 0x28, 0x2b, 0x02, 0x2a, 0x03, 0x00, 0x29, 0x2e, 0x07, 0x04, 0x2d, 0x05, 0x2c, 0x2f, 0x06, 0x02, 0x2b, 0x28, 0x01, 0x29, 0x00, 0x03, 0x2a, 0x03, 0x2a, 0x29, 0x00, 0x28, 0x01, 0x02, 0x2b, 0x2f, 0x06, 0x05, 0x2c, 0x04, 0x2d, 0x2e, 0x07, 0x2f, 0x06, 0x05, 0x2c, 0x04, 0x2d, 0x2e, 0x07, 0x03, 0x2a, 0x29, 0x00, 0x28, 0x01, 0x02, 0x2b, 0x02, 0x2b, 0x28, 0x01, 0x29, 0x00, 0x03, 0x2a, 0x2e, 0x07, 0x04, 0x2d, 0x05, 0x2c, 0x2f, 0x06, 0x01, 0x28, 0x2b, 0x02, 0x2a, 0x03, 0x00, 0x29, 0x2d, 0x04, 0x07, 0x2e, 0x06, 0x2f, 0x2c, 0x05, 0x2c, 0x05, 0x06, 0x2f, 0x07, 0x2e, 0x2d, 0x04, 0x00, 0x29, 0x2a, 0x03, 0x2b, 0x02, 0x01, 0x28, 0x30, 0x19, 0x1a, 0x33, 0x1b, 0x32, 0x31, 0x18, 0x1c, 0x35, 0x36, 0x1f, 0x37, 0x1e, 0x1d, 0x34, 0x1d, 0x34, 0x37, 0x1e, 0x36, 0x1f, 0x1c, 0x35, 0x31, 0x18, 0x1b, 0x32, 0x1a, 0x33, 0x30, 0x19, 0x1e, 0x37, 0x34, 0x1d, 0x35, 0x1c, 0x1f, 0x36, 0x32, 0x1b, 0x18, 0x31, 0x19, 0x30, 0x33, 0x1a, 0x33, 0x1a, 0x19, 0x30, 0x18, 0x31, 0x32, 0x1b, 0x1f, 0x36, 0x35, 0x1c, 0x34, 0x1d, 0x1e, 0x37, 0x1f, 0x36, 0x35, 0x1c, 0x34, 0x1d, 0x1e, 0x37, 0x33, 0x1a, 0x19, 0x30, 0x18, 0x31, 0x32, 0x1b, 0x32, 0x1b, 0x18, 0x31, 0x19, 0x30, 0x33, 0x1a, 0x1e, 0x37, 0x34, 0x1d, 0x35, 0x1c, 0x1f, 0x36, 0x31, 0x18, 0x1b, 0x32, 0x1a, 0x33, 0x30, 0x19, 0x1d, 0x34, 0x37, 0x1e, 0x36, 0x1f, 0x1c, 0x35, 0x1c, 0x35, 0x36, 0x1f, 0x37, 0x1e, 0x1d, 0x34, 0x30, 0x19, 0x1a, 0x33, 0x1b, 0x32, 0x31, 0x18 }, { // Parities of third byte 0x3f, 0x0e, 0x0d, 0x3c, 0x0c, 0x3d, 0x3e, 0x0f, 0x0b, 0x3a, 0x39, 0x08, 0x38, 0x09, 0x0a, 0x3b, 0x0a, 0x3b, 0x38, 0x09, 0x39, 0x08, 0x0b, 0x3a, 0x3e, 0x0f, 0x0c, 0x3d, 0x0d, 0x3c, 0x3f, 0x0e, 0x09, 0x38, 0x3b, 0x0a, 0x3a, 0x0b, 0x08, 0x39, 0x3d, 0x0c, 0x0f, 0x3e, 0x0e, 0x3f, 0x3c, 0x0d, 0x3c, 0x0d, 0x0e, 0x3f, 0x0f, 0x3e, 0x3d, 0x0c, 0x08, 0x39, 0x3a, 0x0b, 0x3b, 0x0a, 0x09, 0x38, 0x08, 0x39, 0x3a, 0x0b, 0x3b, 0x0a, 0x09, 0x38, 0x3c, 0x0d, 0x0e, 0x3f, 0x0f, 0x3e, 0x3d, 0x0c, 0x3d, 0x0c, 0x0f, 0x3e, 0x0e, 0x3f, 0x3c, 0x0d, 0x09, 0x38, 0x3b, 0x0a, 0x3a, 0x0b, 0x08, 0x39, 0x3e, 0x0f, 0x0c, 0x3d, 0x0d, 0x3c, 0x3f, 0x0e, 0x0a, 0x3b, 0x38, 0x09, 0x39, 0x08, 0x0b, 0x3a, 0x0b, 0x3a, 0x39, 0x08, 0x38, 0x09, 0x0a, 0x3b, 0x3f, 0x0e, 0x0d, 0x3c, 0x0c, 0x3d, 0x3e, 0x0f, 0x1f, 0x2e, 0x2d, 0x1c, 0x2c, 0x1d, 0x1e, 0x2f, 0x2b, 0x1a, 0x19, 0x28, 0x18, 0x29, 0x2a, 0x1b, 0x2a, 0x1b, 0x18, 0x29, 0x19, 0x28, 0x2b, 0x1a, 0x1e, 0x2f, 0x2c, 0x1d, 0x2d, 0x1c, 0x1f, 0x2e, 0x29, 0x18, 0x1b, 0x2a, 0x1a, 0x2b, 0x28, 0x19, 0x1d, 0x2c, 0x2f, 0x1e, 0x2e, 0x1f, 0x1c, 0x2d, 0x1c, 0x2d, 0x2e, 0x1f, 0x2f, 0x1e, 0x1d, 0x2c, 0x28, 0x19, 0x1a, 0x2b, 0x1b, 0x2a, 0x29, 0x18, 0x28, 0x19, 0x1a, 0x2b, 0x1b, 0x2a, 0x29, 0x18, 0x1c, 0x2d, 0x2e, 0x1f, 0x2f, 0x1e, 0x1d, 0x2c, 0x1d, 0x2c, 0x2f, 0x1e, 0x2e, 0x1f, 0x1c, 0x2d, 0x29, 0x18, 0x1b, 0x2a, 0x1a, 0x2b, 0x28, 0x19, 0x1e, 0x2f, 0x2c, 0x1d, 0x2d, 0x1c, 0x1f, 0x2e, 0x2a, 0x1b, 0x18, 0x29, 0x19, 0x28, 0x2b, 0x1a, 0x2b, 0x1a, 0x19, 0x28, 0x18, 0x29, 0x2a, 0x1b, 0x1f, 0x2e, 0x2d, 0x1c, 0x2c, 0x1d, 0x1e, 0x2f } }; static const unsigned char hamming_24_18_decode_d1_d4[64] = { 0x00, 0x01, 0x00, 0x01, 0x02, 0x03, 0x02, 0x03, 0x04, 0x05, 0x04, 0x05, 0x06, 0x07, 0x06, 0x07, 0x08, 0x09, 0x08, 0x09, 0x0a, 0x0b, 0x0a, 0x0b, 0x0c, 0x0d, 0x0c, 0x0d, 0x0e, 0x0f, 0x0e, 0x0f, 0x00, 0x01, 0x00, 0x01, 0x02, 0x03, 0x02, 0x03, 0x04, 0x05, 0x04, 0x05, 0x06, 0x07, 0x06, 0x07, 0x08, 0x09, 0x08, 0x09, 0x0a, 0x0b, 0x0a, 0x0b, 0x0c, 0x0d, 0x0c, 0x0d, 0x0e, 0x0f, 0x0e, 0x0f }; // Mapping from parity checks in hamming_24_18_parities to incorrect bit // 0x80000000 - double bit error that can't be corrected static const unsigned int hamming_24_18_decode_correct [64] = { 0x00000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x00000000, 0x00000000, 0x00000000, 0x00000001, 0x00000000, 0x00000002, 0x00000004, 0x00000008, 0x00000000, 0x00000010, 0x00000020, 0x00000040, 0x00000080, 0x00000100, 0x00000200, 0x00000400, 0x00000000, 0x00000800, 0x00001000, 0x00002000, 0x00004000, 0x00008000, 0x00010000, 0x00020000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000 }; #endif