tst.c

#include <stdio.h>
#include "fcs.h"

int main()
{
  unsigned char buf1[] = {0xa0, 0x65,
			  0x01, 0x02,
			  0x01,
			  0x10,
			  0xf0, 0x50};
  
  unsigned char buf2[] = {0xa0, 0x27,
			  0x01, 0x02,
			  0x01,
			  0x10,
			  0x5a, 0x87,
			  0xe6, 0xe7, 0x00,
			  0x0f, 0x40, 0x00, 0x00, 0x00, 0x09, 0x0c, 0x07, 0xd0,
			  0x01, 0x03, 0x01, 0x01, 0x2d, 0x15, 0xff, 0x80, 0x00,
			  0x03, 0x02, 0x01, 0x06, 0x00, 0x00, 0x00, 0x00,
			  0x81, 0xb0};

  /* set default little endian */
  int fb = 0;
  int lb = 1;
  
  if (is_big_endian()) { /* oops, big endian */
    fb = 1;
    fb = 0;
  }

  union {
    unsigned char be[2];
    u16 fcs;
  } sw;

  sw.fcs = pppfcs16(PPPINITFCS16, buf1, 6) ^0xffff; printf("%02x %02x\n", sw.be[fb], sw.be[lb]);
  sw.fcs = pppfcs16(PPPINITFCS16, buf2, 6) ^0xffff; printf("%02x %02x\n",  sw.be[fb], sw.be[lb]);
  sw.fcs = pppfcs16(PPPINITFCS16, buf2, 37) ^0xffff; printf("%02x %02x\n", sw.be[fb], sw.be[lb]);

  return 0;
}

/* end of file */