#include "project.h"

int check_parity (uint8_t *d, unsigned s, unsigned e, uint8_t p)
{
  unsigned i;

  for (i = s; i <= e; ++i)
    p ^= d[i];

  return !p;
}


unsigned bcd (uint8_t *d, unsigned s, unsigned e)
{
  unsigned ret = 0, c, b, i;

  for (i = e, c = 1, b = 0; i >= s; --i, b++) {

    if (d[i]) ret += c;


    switch (b & 3) {
    case 0:
    case 1:
    case 2:
      c <<= 1;
      break;

    default:
      c >>= 3;
      c *= 10;
    }
  }

  return ret;
}



unsigned le_bcd (uint8_t *d, unsigned s, unsigned e)
{
  unsigned ret = 0, c, b, i;

  for (i = s, c = 1, b = 0; i <= e; ++i, b++) {

    if (d[i]) ret += c;


    switch (b & 3) {
    case 0:
    case 1:
    case 2:
      c <<= 1;
      break;

    default:
      c >>= 3;
      c *= 10;
    }
  }

  return ret;
}