SHT30 51单片机驱动程序 - - Powered by Discuz!

#include "SHT3X.H"
/*================================================================
【名称】
【功能】模拟IIC使用的引脚定义，注意要上拉电阻
【备注】
【作者】
【时间】
================================================================*/
//sbit SDA=P3^3; //大板子引脚定义
//sbit SCL=P5^4;
sbit SDA=P5^4; //小板子引脚定义
sbit SCL=P3^3;
#define POLYNOMIAL 0x31 // P(x) = x^8 + x^5 + x^4 + 1 = 00110001
//==============================================================================
unsigned char SHT3X_CalcCrc(unsigned char *crcdata, unsigned char nbrOfBytes){
//==============================================================================
unsigned char Bit; // bit mask
unsigned char crc = 0xFF; // calculated checksum
unsigned char byteCtr; // byte counter
// calculates 8-Bit checksum with given polynomial
for(byteCtr = 0; byteCtr < nbrOfBytes; byteCtr++)
{
crc ^= (crcdata[byteCtr]);
for(Bit = 8; Bit > 0; --Bit)
{
if(crc & 0x80) crc = (crc << 1) ^ POLYNOMIAL;
else crc = (crc << 1);
}
}
return crc;
}

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