private unsafe void CCT_AddChecksum(int idx)
{
ushort num = 0;
switch (bChecksumType)
{
case CHECKSUMTYPE.CHK8BIT:
{
for (int i = 0; i < msgTxLen[idx]; i++)
{
num = (ushort)(num + cct_tx[idx][i]);
}
num = (byte)(-num);
cct_tx[idx][msgTxLen[idx]++] = (byte)(num & 0xFF);
break;
}
case CHECKSUMTYPE.CRC16BIT:
fixed(byte *pC = cct_tx[idx])
{
fixed(byte *pC2 = &cct_tx[idx][3])
{
num = CCtalkUtilityDll.crcCalculation(2, pC, 0);
num = CCtalkUtilityDll.crcCalculation(msgTxLen[idx] - 3, pC2, num);
}
}
cct_tx[idx][msgTxLen[idx]++] = (byte)((num & 0xFF00) >> 8);
cct_tx[idx][2] = (byte)(num & 0xFF);
break;
}
}
private unsafe ushort CCT_VerifyChecksum(int nBytes)
{
ushort num = 0;
switch (bChecksumType)
{
case CHECKSUMTYPE.CHK8BIT:
{
for (int i = 0; i < nBytes; i++)
{
num = (ushort)(num + cct_rx[i]);
}
return(num);
}
case CHECKSUMTYPE.CRC16BIT:
{
byte[] array = new byte[2]
{
cct_rx[nBytes - 1],
cct_rx[2]
};
fixed(byte *pC = cct_rx)
{
fixed(byte *pC2 = &cct_rx[3])
{
fixed(byte *pC3 = array)
{
num = CCtalkUtilityDll.crcCalculation(2, pC, 0);
num = CCtalkUtilityDll.crcCalculation(nBytes - 3, pC2, num);
num = CCtalkUtilityDll.crcCalculation(2, pC3, num);
}
}
}
return(num);
}
default:
return(num);
}
}
