SIYI HM30 - Page 96

HM30 User Manual v1.3
88
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2) USB COM (USB to Serial) (Baud rate is the same with datalink baud rate)
3) Bluetooth
4) MK15 RC Upgrade Port / MK32 RC Type-C Port (Virtual serial port based on USB port)
4.8.4 SDK CRC16 Check Code
const uint16_t crc16_tab[256];
/***********************************************************
CRC16 Coding & Decoding G(X) = X^16+X^12+X^5+1
***********************************************************/
uint16_t CRC16_cal(uint8_t *ptr, uint32_t len, uint16_t crc_init)
{
uint16_t crc, oldcrc16;
uint8_t temp;
crc = crc_init;
while (len--!=0)
{
temp=(crc>>8)&0xff;
oldcrc16=crc16_tab[*ptr^temp];
crc=(crc<<8)^oldcrc16;
ptr++;
}
//crc=~crc; //??
return(crc);
}
uint8_t crc_check_16bites(uint8_t* pbuf, uint32_t len,uint32_t* p_result)
{
uint16_t crc_result = 0;
crc_result= CRC16_cal(pbuf,len, 0);
*p_result = crc_result;
return 2;