gistfile1.txt

#include <stdlib.h>
#include <stdio.h>

int main(int argc, char* argv[])
{
   FILE* f = fopen("robotron.nv", "r");
   FILE* fout = fopen("robotron-converted", "w");
   int a, b, c;
   do
   {
      a = fgetc(f);
      b = fgetc(f);
      c = ((a & 0xF) << 4) + (b & 0xF);
      printf("%x ", c);
      fwrite(&c, 1, 1, fout);
   } while (b != EOF);
   fclose(fout);
}