/* Conversion lookup tables from conventional alpha to Berlekamp's * dual-basis representation. Used in the CCSDS version only. * taltab[] -- convert conventional to dual basis * tal1tab[] -- convert dual basis to conventional * Note: the actual RS encoder/decoder works with the conventional basis. * So data is converted from dual to conventional basis before either * encoding or decoding and then converted back. * * Copyright 2002 Phil Karn, KA9Q * May be used under the terms of the GNU General Public License (GPL) */#include <stdio.h>#define DTYPE unsigned charDTYPE Taltab[256],Tal1tab[256];static DTYPE tal[] = { 0x8d, 0xef, 0xec, 0x86, 0xfa, 0x99, 0xaf, 0x7b };/* Generate conversion lookup tables between conventional alpha representation * (@**7, @**6, ...@**0) *  and Berlekamp's dual basis representation * (l0, l1, ...l7) */int main(){  int i,j,k;  for(i=0;i<256;i++){/* For each value of input */    Taltab[i] = 0;    for(j=0;j<8;j++) /* for each column of matrix */      for(k=0;k<8;k++){ /* for each row of matrix */	if(i & (1<<k))	   Taltab[i] ^= tal[7-k] & (1<<j);      }    Tal1tab[Taltab[i]] = i;  }  printf("unsigned char Taltab[] = {\n");  for(i=0;i<256;i++){    if((i % 16) == 0)      printf("\n");    printf("0x%02x,",Taltab[i]);  }  printf("\n};\n\nunsigned char Tal1tab[] = {");  for(i=0;i<256;i++){    if((i % 16) == 0)      printf("\n");    printf("0x%02x,",Tal1tab[i]);  }  printf("\n};\n");  exit(0);}