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39 lines
973 B
C
39 lines
973 B
C
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/* Configure the RS codec with fixed parameters for CCSDS standard
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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 2002 Phil Karn, KA9Q
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* May be used under the terms of the GNU General Public License (GPL)
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*/
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#define DTYPE unsigned char
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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 unsigned char CCSDS_alpha_to[];
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extern unsigned char CCSDS_index_of[];
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extern unsigned char 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 A0 (NN)
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#define ENCODE_RS encode_rs_8
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#define DECODE_RS decode_rs_8
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void ENCODE_RS(DTYPE *data,DTYPE *parity);
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int DECODE_RS(DTYPE *data, int *eras_pos, int no_eras);
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