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34 lines
785 B
C
34 lines
785 B
C
/* Stuff specific to the CCSDS (255,223) RS codec
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* (255,223) code over GF(256). Note: the conventional basis is still
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* used; the dual-basis mappings are performed in [en|de]code_rs_ccsds.c
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*
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* Copyright 2003 Phil Karn, KA9Q
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* May be used under the terms of the GNU Lesser General Public License (LGPL)
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*/
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typedef unsigned char data_t;
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static inline int mod255(int x){
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while (x >= 255) {
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x -= 255;
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x = (x >> 8) + (x & 255);
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}
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return x;
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}
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#define MODNN(x) mod255(x)
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extern data_t CCSDS_alpha_to[];
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extern data_t CCSDS_index_of[];
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extern data_t CCSDS_poly[];
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#define MM 8
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#define NN 255
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#define ALPHA_TO CCSDS_alpha_to
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#define INDEX_OF CCSDS_index_of
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#define GENPOLY CCSDS_poly
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#define NROOTS 32
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#define FCR 112
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#define PRIM 11
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#define IPRIM 116
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#define PAD pad
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