#include "sdbp.h"
#include "tdgnss.h"



int BaudsArray[8] = {4800,4800,9600,19200,38400,57600,115200,230400};

byte sync_head[2] = {0x23,0x3E};

ID ackID     = { 0x01, 0x01 };
ID nackID     = { 0x01, 0x02 };
ID enterID     = { 0xA0, 0x01 };
ID confirmID   = { 0xA0, 0x02 };
ID eraseID     = { 0xA0, 0x03 };
ID writeID     = { 0xA0, 0x04 };
ID rebootID   = { 0xA0, 0x05 };
ID uartID     = { 0x03, 0x21 };
ID verID     = { 0x05, 0x01 };

static void InputNoData(ID id)
{

  byte buf[10];
  int len;
  int fc = 0;
  buf[0] = 0x23;
  buf[1] = 0x3E;
  buf[2] = id.type;
  buf[3] = id.funcode;
  buf[4] = 0x00;
  buf[5] = 0x00;
  fc = FletCher16_sdbp(buf, 2, 4);
  buf[6] = (byte)fc;
  buf[7] = (byte)(fc >> 8);
  len = 8;
  TxData(buf, len);    
}

int FletCher16_sdbp(byte* buffer, int offset, int count)
{
    byte fc1=0,fc2=0;
    int i;
    for (i = 0; i < count; i++)
    {
        fc1 += buffer[offset+i];
        fc2 += fc1;
    }
    return (fc2 << 8) + (fc1 & 0xFF);
}
//check the buf is a correct SDBP message or not 
int GetFirstSyncFrame(byte* bufRead, int len, int* head, int* tail)
{
    int i;
    int len_f =0 ;
    int fc = 0;

    if (len <0)
        return 0;
    
    for (i = 0; i <= len; i++)
    {
         if(bufRead[i] == sync_head[0] && (bufRead[i+1] == sync_head[1]))
         {
            len_f = bufRead[i+4] +  (bufRead[i+5] <<8);
            fc=bufRead[i+6+len_f] +  (bufRead[i+6+len_f+1] <<8);
            if(FletCher16_sdbp((byte*)bufRead,i+2,len_f+4) == fc)                        
            {
              *head = i;
        *tail = i+6+len_f+2;
                return 1;
            }
         }
    }

    return 0;
}

byte CheckImgFile(const byte *filedatas, int startpoint, int filelen)
{
  if(filedatas == NULL || startpoint < 0 || filelen < IMGFILE_HEADREAR_LEN)
    return 0;

  if(filedatas[startpoint] != 0x14 || filedatas[startpoint + 1] != 0x56 || filedatas[startpoint + 2] != 0x10  || filedatas[startpoint + 3] != 0x70)
  {  
    return 0;
  }
  
  
  return 1;
}

byte CheckImgData1(const byte *filedatas, int startpoint, int filelen)
{
  if(filedatas == NULL || startpoint < 0 || filelen < IMGFILE_HEADREAR_LEN)
    return 0;

  if(filedatas[startpoint] != 0x14 || filedatas[startpoint + 1] != 0x56 || filedatas[startpoint + 2] != 0x11  || filedatas[startpoint + 3] != 0x11)
  {  
    return 0;
  }
  
  
  return 1;
}


byte CheckImgData2(const byte *filedatas, int startpoint, int filelen)
{
  if(filedatas == NULL || startpoint < 0 || filelen < IMGFILE_HEADREAR_LEN)
    return 0;

  if(filedatas[startpoint] != 0x14 || filedatas[startpoint + 1] != 0x56 || filedatas[startpoint + 2] != 0x22  || filedatas[startpoint + 3] != 0x22)
  {  
    return 0;
  }
  
  
  return 1;
}

/*
 *
 * SDBP FUNC
 *
 */
int SDBP_PUB_ACK(byte* bufRead, ID id,int idx)
{
  if(idx <0)
    return 0;
  if(bufRead[idx+2] != 0x01 || bufRead[idx+3] != 0x01)
    return 0;
  if(bufRead[idx+6] == id.type && bufRead[idx+7] == id.funcode)
    return 1;

  return 0;
}

int SDBP_PUB_NACK(byte* bufRead, ID id,int idx)
{
  if(idx <0)
    return 0;
  if(bufRead[idx+2] != nackID.type || bufRead[idx+3] != nackID.funcode)
    return 0;
  if(bufRead[idx+6] == id.type && bufRead[idx+7] == id.funcode)
    return 1;
  return 0;
}

int SDBP_NACK(byte* bufRead, int idx)
{
  if (idx < 0)
    return 0;
  if (bufRead[idx + 2] == nackID.type || bufRead[idx + 3] == nackID.funcode)
    return 1;
  return 0;
}


void SDBP_UPD_ENTER(void)
{
    InputNoData(enterID);
    usleep(100000);//100 ms
}

void SDBP_UPD_CONFIRM_I(void)
{
  InputNoData(confirmID);
}


int SDBP_UPD_CONFIRM_O(byte* bufRead, int idx)
{
  if(idx <0)
    return 0;
  if(bufRead[idx+2] != confirmID.type || bufRead[idx+3] != confirmID.funcode)
    return 0;

  if(bufRead[idx+6])
    return 0;
  else
    return 1;
}

void SDBP_CANCEL_PROTECT_I_C1()
{
    bufWrite[0] = 0x23;
    bufWrite[1] = 0x3E;
    bufWrite[2] = 0xBE;
    bufWrite[3] = 0x04;
    bufWrite[4] = 0x0B;
    bufWrite[5] = 0x00;
    bufWrite[6] = 0x47;
    bufWrite[7] = 0x44;
    bufWrite[8] = 0x10;
    bufWrite[9] = 0x20;
    bufWrite[10] = 0x01;
    bufWrite[11] = 0x40;
    bufWrite[12] = 0x01;
    bufWrite[13] = 0x01;
    bufWrite[14] = 0x00;
    bufWrite[15] = 0x00;
    bufWrite[16] = 0x00;
    bufWrite[17] = 0xCB;
    bufWrite[18] = 0xBE;
    int iLenToWrite = 19;
    TxData(bufWrite, iLenToWrite);
}
void SDBP_CANCEL_PROTECT_I_C2()
{
    bufWrite[0] = 0x23;
    bufWrite[1] = 0x3E;
    bufWrite[2] = 0xBE;
    bufWrite[3] = 0x04;
    bufWrite[4] = 0x0B;
    bufWrite[5] = 0x00;
    bufWrite[6] = 0x47;
    bufWrite[7] = 0x44;
    bufWrite[8] = 0x0C;
    bufWrite[9] = 0x20;
    bufWrite[10] = 0x01;
    bufWrite[11] = 0x40;
    bufWrite[12] = 0x01;
    bufWrite[13] = 0x01;
    bufWrite[14] = 0x00;
    bufWrite[15] = 0x00;
    bufWrite[16] = 0x00;
    bufWrite[17] = 0xC7;
    bufWrite[18] = 0x9A;
    int iLenToWrite = 19;
    TxData(bufWrite, iLenToWrite);
}
void SDBP_CANCEL_PROTECT_I_C3()
{
    bufWrite[0] = 0x23;
    bufWrite[1] = 0x3E;
    bufWrite[2] = 0xBE;
    bufWrite[3] = 0x04;
    bufWrite[4] = 0x0B;
    bufWrite[5] = 0x00;
    bufWrite[6] = 0x47;
    bufWrite[7] = 0x44;
    bufWrite[8] = 0x1C;
    bufWrite[9] = 0x20;
    bufWrite[10] = 0x01;
    bufWrite[11] = 0x40;
    bufWrite[12] = 0x01;
    bufWrite[13] = 0x06;
    bufWrite[14] = 0x00;
    bufWrite[15] = 0x00;
    bufWrite[16] = 0x00;
    bufWrite[17] = 0xDC;
    bufWrite[18] = 0x3E;
    int iLenToWrite = 19;
    TxData(bufWrite, iLenToWrite);
}
void SDBP_CANCEL_PROTECT_I_C4()
{
    bufWrite[0] = 0x23;
    bufWrite[1] = 0x3E;
    bufWrite[2] = 0xBE;
    bufWrite[3] = 0x04;
    bufWrite[4] = 0x0B;
    bufWrite[5] = 0x00;
    bufWrite[6] = 0x47;
    bufWrite[7] = 0x44;
    bufWrite[8] = 0x1C;
    bufWrite[9] = 0x20;
    bufWrite[10] = 0x01;
    bufWrite[11] = 0x40;
    bufWrite[12] = 0x01;
    bufWrite[13] = 0x01;
    bufWrite[14] = 0x00;
    bufWrite[15] = 0x00;
    bufWrite[16] = 0x00;
    bufWrite[17] = 0xD7;
    bufWrite[18] = 0x2A;
    int iLenToWrite = 19;
    TxData(bufWrite, iLenToWrite);
}
void SDBP_CANCEL_PROTECT_I_C5()
{
    bufWrite[0] = 0x23;
    bufWrite[1] = 0x3E;
    bufWrite[2] = 0xBE;
    bufWrite[3] = 0x04;
    bufWrite[4] = 0x0B;
    bufWrite[5] = 0x00;
    bufWrite[6] = 0x47;
    bufWrite[7] = 0x44;
    bufWrite[8] = 0x1C;
    bufWrite[9] = 0x20;
    bufWrite[10] = 0x01;
    bufWrite[11] = 0x40;
    bufWrite[12] = 0x01;
    bufWrite[13] = 0x00;
    bufWrite[14] = 0x00;
    bufWrite[15] = 0x00;
    bufWrite[16] = 0x00;
    bufWrite[17] = 0xD6;
    bufWrite[18] = 0x26;
    int iLenToWrite = 19;
    TxData(bufWrite, iLenToWrite);
}
void SDBP_CANCEL_PROTECT_I_C6()
{
    bufWrite[0] = 0x23;
    bufWrite[1] = 0x3E;
    bufWrite[2] = 0xBE;
    bufWrite[3] = 0x04;
    bufWrite[4] = 0x0B;
    bufWrite[5] = 0x00;
    bufWrite[6] = 0x47;
    bufWrite[7] = 0x44;
    bufWrite[8] = 0x1C;
    bufWrite[9] = 0x20;
    bufWrite[10] = 0x01;
    bufWrite[11] = 0x40;
    bufWrite[12] = 0x01;
    bufWrite[13] = 0x05;
    bufWrite[14] = 0x00;
    bufWrite[15] = 0x00;
    bufWrite[16] = 0x00;
    bufWrite[17] = 0xDB;
    bufWrite[18] = 0x3A;
    int iLenToWrite = 19;
    TxData(bufWrite, iLenToWrite);
}
void SDBP_CANCEL_PROTECT_I_C7()
{
    bufWrite[0] = 0x23;
    bufWrite[1] = 0x3E;
    bufWrite[2] = 0xBE;
    bufWrite[3] = 0x04;
    bufWrite[4] = 0x0B;
    bufWrite[5] = 0x00;
    bufWrite[6] = 0x47;
    bufWrite[7] = 0x44;
    bufWrite[8] = 0x1C;
    bufWrite[9] = 0x20;
    bufWrite[10] = 0x01;
    bufWrite[11] = 0x40;
    bufWrite[12] = 0x01;
    bufWrite[13] = 0x00;
    bufWrite[14] = 0x01;
    bufWrite[15] = 0x00;
    bufWrite[16] = 0x00;
    bufWrite[17] = 0xD7;
    bufWrite[18] = 0x29;
    int iLenToWrite = 19;
    TxData(bufWrite, iLenToWrite);
}
void SDBP_CANCEL_PROTECT_I_C8()
{
    bufWrite[0] = 0x23;
    bufWrite[1] = 0x3E;
    bufWrite[2] = 0xBE;
    bufWrite[3] = 0x03;
    bufWrite[4] = 0x07;
    bufWrite[5] = 0x00;
    bufWrite[6] = 0x47;
    bufWrite[7] = 0x44;
    bufWrite[8] = 0x20;
    bufWrite[9] = 0x20;
    bufWrite[10] = 0x01;
    bufWrite[11] = 0x40;
    bufWrite[12] = 0x01;
    bufWrite[13] = 0xD5;
    bufWrite[14] = 0xB4;
    int iLenToWrite = 15;
    TxData(bufWrite, iLenToWrite);
}




void SDBP_UPD_ERASE_I1(void)
{
  InputNoData(eraseID);
}

void SDBP_UPD_ERASE_I2(int num)
{
  int iLenToWrite;
  int fc = 0;
  bufWrite[0] = 0x23;
  bufWrite[1] = 0x3E;
  bufWrite[2] = eraseID.type;
  bufWrite[3] = eraseID.funcode;
  bufWrite[4] = 0x02;
  bufWrite[5] = 0x00;
  bufWrite[6] = (byte)num;
  bufWrite[7] =  (byte)(num>>8);
  fc = FletCher16_sdbp(bufWrite, 2,6);
  bufWrite[8] = (byte)fc;
  bufWrite[9] = (byte)(fc >> 8);
  iLenToWrite = 10;
  TxData(bufWrite, iLenToWrite);
}

int SDBP_UPD_ERASE_O1(byte* bufRead, int idx)
{
  if (idx < 0)
    return 0;
  if (bufRead[idx + 2] != eraseID.type || bufRead[idx + 3] != eraseID.funcode)
    return 0;

  if(bufRead[idx + 6])
    return 0;
  else
    return 1;
}
int SDBP_UPD_ERASE_O2(byte* bufRead, int idx, int num)
{
    (void)num;
  if (idx < 0)
    return -1;
  if (bufRead[idx + 2] != eraseID.type || bufRead[idx + 3] != eraseID.funcode)
    return -1;
  num = bufRead[idx + 7]  + (bufRead[idx + 8]<<8);
  return bufRead[idx + 6];
}

int SDBP_UPD_WRITE_I(byte* datas,int offset,int datalen)
{
  int sum = 0;
  int i;
  int iLenToWrite;
  for (i = 0; i < datalen; i++)
  {
    sum+=datas[i+offset] ;
  }
  if (sum == datalen * 0xff)
  {
    return 0;
  }

  int fc = 0;
  bufWrite[0] = 0x23;
  bufWrite[1] = 0x3E;
  bufWrite[2] = writeID.type ;
  bufWrite[3] = writeID.funcode;
  bufWrite[4] = (byte)(datalen+6);
  bufWrite[5] = (byte)((datalen+6) >> 8);
  bufWrite[6] = (byte)offset;
  bufWrite[7] = (byte)(offset >> 8);
  bufWrite[8] = (byte)(offset>>16);
  bufWrite[9] = (byte)(offset >>24);
  bufWrite[10] = (byte)datalen;
  bufWrite[11] = (byte)(datalen >> 8);
//  Array.Copy(datas, offset, bufWrite, 12,datalen);
  memcpy(&bufWrite[12],&datas[offset],datalen);
  fc = FletCher16_sdbp(bufWrite, 2, datalen+10);
  bufWrite[datalen + 12] = (byte)fc;
  bufWrite[datalen + 13] = (byte)(fc >> 8);
  iLenToWrite = datalen+14;

  TxData(bufWrite, iLenToWrite);
  return 1;
}

int SDBP_UPD_WRITE_O(byte* bufRead, int idx)
{
  if (idx < 0)
    return -1;
  if (bufRead[idx + 2] != writeID.type || bufRead[idx + 3] != writeID.funcode)
    return -1;
  if(bufRead[idx + 6])
    return 0;
  else
    return 1;
}

void SDBP_CFG_UART_I(UARTPara uartpara,byte autosave)
{
  int iLenToWrite;
  int fc = 0;
  bufWrite[0] = 0x23;
  bufWrite[1] = 0x3E;
  bufWrite[2] = 0x03;
  bufWrite[3] = 0x21;
  bufWrite[4] = 0x06;
  bufWrite[5] = 0x00;
  bufWrite[6] = uartpara.com;
  bufWrite[7] = uartpara.baudrate;
  bufWrite[8] = uartpara.databit;
  bufWrite[9] = uartpara.stopbit;
  bufWrite[10] = uartpara.checkbit;
  bufWrite[11] = autosave;
  fc = FletCher16_sdbp(bufWrite, 2, 10);
  bufWrite[12] = (byte)fc;
  bufWrite[13] = (byte)(fc >> 8);
  iLenToWrite = 14;
  TxData(bufWrite, iLenToWrite);
}

void SDBP_UPD_REBOOT()
{
  InputNoData(rebootID);
}

void SDBP_DBG_FLASH_I(int offset,int num)
{
  int iLenToWrite;
  int fc = 0;
  bufWrite[0] = 0x23;
  bufWrite[1] = 0x3E;
  bufWrite[2] = 0xBE;
  bufWrite[3] = 0x08;
  bufWrite[4] = 0x08;
  bufWrite[5] = 0x00;
  bufWrite[6] =0x47;
  bufWrite[7] =0x44;
  bufWrite[8] = (byte)(offset);
  bufWrite[9] = (byte)(offset>>8);
  bufWrite[10] = (byte)(offset>>16);
  bufWrite[11] = (byte)(offset >> 24);
  bufWrite[12] = (byte)(num);
  bufWrite[13] = (byte)(num>>8);
  fc = FletCher16_sdbp(bufWrite, 2, 12);
  bufWrite[14] = (byte)fc;
  bufWrite[15] = (byte)(fc >> 8);
  iLenToWrite = 16;
  TxData(bufWrite, iLenToWrite);
}


int SDBP_DBG_FLASH_O(byte* bufRead, int idx,byte* datas,int offset, int len)
{
  if (idx < 0)
    return -1;
  int offset1 = bufRead[idx + 6] + (bufRead[idx + 7] << 8) +
              (bufRead[idx + 8] << 16) + (bufRead[idx + 9] << 24);
  int len1 = bufRead[idx +10] + (bufRead[idx + 11] << 8);
  if (offset1 != offset || len != len1)
    return -1;
  memcpy(&datas[offset],&bufRead[idx + 12],len);
  return len;
}

void SDBP_QUE_VER_I(void)
{
    InputNoData(verID);
}

int SDBP_QUE_VER_O(byte* bufRead, int idx)
{
  int len;

    if (idx < 0)
    return 0;
    if (bufRead[idx + 2] != verID.type || bufRead[idx + 3] != verID.funcode)
    return 0;
    len = bufRead[idx +4]  + (bufRead[idx +5] <<8);
    if(len>150)
    return 0;

    return 1;

}

unsigned char CRC16TabH[256] =
{
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
  0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
};

unsigned char CRC16TabL[256] =
{
  0x00, 0xC0, 0xC1, 0x01, 0xC3, 0x03, 0x02, 0xC2,
  0xC6, 0x06, 0x07, 0xC7, 0x05, 0xC5, 0xC4, 0x04,
  0xCC, 0x0C, 0x0D, 0xCD, 0x0F, 0xCF, 0xCE, 0x0E,
  0x0A, 0xCA, 0xCB, 0x0B, 0xC9, 0x09, 0x08, 0xC8,
  0xD8, 0x18, 0x19, 0xD9, 0x1B, 0xDB, 0xDA, 0x1A,
  0x1E, 0xDE, 0xDF, 0x1F, 0xDD, 0x1D, 0x1C, 0xDC,
  0x14, 0xD4, 0xD5, 0x15, 0xD7, 0x17, 0x16, 0xD6,
  0xD2, 0x12, 0x13, 0xD3, 0x11, 0xD1, 0xD0, 0x10,
  0xF0, 0x30, 0x31, 0xF1, 0x33, 0xF3, 0xF2, 0x32,
  0x36, 0xF6, 0xF7, 0x37, 0xF5, 0x35, 0x34, 0xF4,
  0x3C, 0xFC, 0xFD, 0x3D, 0xFF, 0x3F, 0x3E, 0xFE,
  0xFA, 0x3A, 0x3B, 0xFB, 0x39, 0xF9, 0xF8, 0x38,
  0x28, 0xE8, 0xE9, 0x29, 0xEB, 0x2B, 0x2A, 0xEA,
  0xEE, 0x2E, 0x2F, 0xEF, 0x2D, 0xED, 0xEC, 0x2C,
  0xE4, 0x24, 0x25, 0xE5, 0x27, 0xE7, 0xE6, 0x26,
  0x22, 0xE2, 0xE3, 0x23, 0xE1, 0x21, 0x20, 0xE0,
  0xA0, 0x60, 0x61, 0xA1, 0x63, 0xA3, 0xA2, 0x62,
  0x66, 0xA6, 0xA7, 0x67, 0xA5, 0x65, 0x64, 0xA4,
  0x6C, 0xAC, 0xAD, 0x6D, 0xAF, 0x6F, 0x6E, 0xAE,
  0xAA, 0x6A, 0x6B, 0xAB, 0x69, 0xA9, 0xA8, 0x68,
  0x78, 0xB8, 0xB9, 0x79, 0xBB, 0x7B, 0x7A, 0xBA,
  0xBE, 0x7E, 0x7F, 0xBF, 0x7D, 0xBD, 0xBC, 0x7C,
  0xB4, 0x74, 0x75, 0xB5, 0x77, 0xB7, 0xB6, 0x76,
  0x72, 0xB2, 0xB3, 0x73, 0xB1, 0x71, 0x70, 0xB0,
  0x50, 0x90, 0x91, 0x51, 0x93, 0x53, 0x52, 0x92,
  0x96, 0x56, 0x57, 0x97, 0x55, 0x95, 0x94, 0x54,
  0x9C, 0x5C, 0x5D, 0x9D, 0x5F, 0x9F, 0x9E, 0x5E,
  0x5A, 0x9A, 0x9B, 0x5B, 0x99, 0x59, 0x58, 0x98,
  0x88, 0x48, 0x49, 0x89, 0x4B, 0x8B, 0x8A, 0x4A,
  0x4E, 0x8E, 0x8F, 0x4F, 0x8D, 0x4D, 0x4C, 0x8C,
  0x44, 0x84, 0x85, 0x45, 0x87, 0x47, 0x46, 0x86,
  0x82, 0x42, 0x43, 0x83, 0x41, 0x81, 0x80, 0x40
};

unsigned short CalcCRC16(const char *datas, int startpoint, int len)
{
  unsigned short crc = 0;
  unsigned char crc_h = 0;
  unsigned char crc_l = 0;
  unsigned char tmp;
  int len_all = len + startpoint;
  int i;

  if(startpoint < 0 )
    return 0;
  

  for (i = startpoint; i < len_all; i++)
  {
    tmp = crc_h ^ datas[i];
    crc_h = crc_l ^ CRC16TabH[tmp];
    crc_l = CRC16TabL[tmp];
  }

  crc = (((unsigned short) crc_h) << 8) + (unsigned short)crc_l;

  return crc;
}