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

/*********************************************************************/
uint32_t reverse(uint32_t x, int bits)
/*********************************************************************/
{
    x = ((x & 0x55555555) << 1) | ((x & 0xAAAAAAAA) >> 1); // Swap _<>_
    x = ((x & 0x33333333) << 2) | ((x & 0xCCCCCCCC) >> 2); // Swap __<>__
    x = ((x & 0x0F0F0F0F) << 4) | ((x & 0xF0F0F0F0) >> 4); // Swap ____<>____
    x = ((x & 0x00FF00FF) << 8) | ((x & 0xFF00FF00) >> 8); // Swap ...
    x = ((x & 0x0000FFFF) << 16) | ((x & 0xFFFF0000) >> 16); // Swap ...
    return x >> (32 - bits) ;
}
/*********************************************************************/
uint32_t crcX(uint32_t crc, uint8_t databit, uint32_t mirrpoly )
/*********************************************************************/
{ // der braucht das gespiegelte Polynom
    crc = crc ^ (databit&1);
    if(crc&1)
      crc=(crc>>1)^mirrpoly;
    else
      crc=(crc>>1);
  return(crc);
}

/*******************************************************************/
uint32_t crc32(uint32_t crc, uint8_t byte)
/*******************************************************************/
{
int8_t i;
  crc = crc ^ byte;
  for(i=7; i>=0; i--)
    crc=(crc>>1)^(0xedb88320ul & (-(crc&1)));
  return(crc);
}

/*******************************************************************/
uint32_t crc16(uint16_t crc, uint8_t byte)
/*******************************************************************/
{
int8_t i;
  crc = crc ^ byte;
  for(i=7; i>=0; i--)
    crc=(crc>>1)^(0xa001u & (-(crc&1)));
  return(crc);
}


/*******************************************************************/
int main(int  argc , char ** argv)
/*******************************************************************/

{

uint32_t reg = 0xffffffff;
uint32_t reg16 = 0x0000,regreg;
int16_t y[2];
int16_t n,k,m;
int16_t yalt[2];

uint32_t poly32=reverse(0x04c11db7,32);
uint32_t poly7 =reverse(0x09,7);
uint32_t poly16 =0xa001u;

uint32_t poly;
uint8_t npoly;
uint32_t crc;


reg16=crc16(reg16,'0');
reg16=crc16(reg16,'1');
reg16=crc16(reg16,'2');
reg16=crc16(reg16,'3');
//printf("%04x  %04x  \n",reg16,reg16^0xffff);

reg = 0xffffffff;
reg=crc32(reg,(uint8_t)0x20);
reg=crc32(reg,(uint8_t)0x00);
reg=crc32(reg,(uint8_t)0x07);
reg=crc32(reg,(uint8_t)0x70);

reg=crc32(reg,(uint8_t)0x26);
reg=crc32(reg,(uint8_t)0x68);
reg=crc32(reg,(uint8_t)0xcd);
reg=crc32(reg,(uint8_t)0x61);

printf("%08x  %08x  \n",reg,reg^0xffffffff);

reg  = 0xffffffff;
poly = poly32;
for(k=0;k<8;k++) reg=crcX(reg,(uint8_t)((0x20>>k)&1),poly);
for(k=0;k<8;k++) reg=crcX(reg,(uint8_t)((0x00>>k)&1),poly);
for(k=0;k<8;k++) reg=crcX(reg,(uint8_t)((0x07>>k)&1),poly);
for(k=0;k<8;k++) reg=crcX(reg,(uint8_t)((0x70>>k)&1),poly);
for(k=0;k<8;k++) reg=crcX(reg,(uint8_t)((0x26>>k)&1),poly);
for(k=0;k<8;k++) reg=crcX(reg,(uint8_t)((0x68>>k)&1),poly);
for(k=0;k<8;k++) reg=crcX(reg,(uint8_t)((0xcd>>k)&1),poly);
for(k=0;k<8;k++) reg=crcX(reg,(uint8_t)((0x61>>k)&1),poly);
printf("%08x  %08x  \n",reg,reg^0xffffffff);

reg  = 0x7f;
poly = poly7;
// 9 Bit senden
reg=crcX(reg,0,poly);
reg=crcX(reg,1,poly);
reg=crcX(reg,0,poly);
reg=crcX(reg,1,poly);
reg=crcX(reg,0,poly);
reg=crcX(reg,1,poly);
reg=crcX(reg,0,poly);
reg=crcX(reg,1,poly);
reg=crcX(reg,1,poly);
// CRC7 ist 0x49

reg=crcX(reg,1,poly);
reg=crcX(reg,0,poly);
reg=crcX(reg,0,poly);
reg=crcX(reg,1,poly);
reg=crcX(reg,0,poly);
reg=crcX(reg,0,poly);
reg=crcX(reg,1,poly);


//for(k=0;k<8;k++) reg=crcX(reg,(uint8_t)((0x26>>k)&1),poly);
//for(k=0;k<8;k++) reg=crcX(reg,(uint8_t)((0x68>>k)&1),poly);
//for(k=0;k<8;k++) reg=crcX(reg,(uint8_t)((0xcd>>k)&1),poly);
//for(k=0;k<8;k++) reg=crcX(reg,(uint8_t)((0x61>>k)&1),poly);
printf("%08x  %08x  \n",reg,poly7);




return;

}