执行演示代码

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

#include <stdint.h> 
#include <getopt.h> 
#include <fcntl.h> 
#include <sys/ioctl.h> 
#include <linux/types.h> 
#include <linux/i2c.h>
#include <linux/i2c-dev.h> 

//i2c address
#define SHTC3_I2C_ADDRESS	    0x70
#define I2C_DEVICE		    "/dev/i2c-1"

//Commands
#define SHTC3_WakeUp                0x3517
#define SHTC3_Sleep                 0xB098
#define SHTC3_NM_CE_ReadTH          0x7CA2
#define SHTC3_NM_CE_ReadRH          0x5C24
#define SHTC3_NM_CD_ReadTH          0x7866
#define SHTC3_NM_CD_ReadRH          0x58E0
#define SHTC3_LM_CE_ReadTH          0x6458
#define SHTC3_LM_CE_ReadRH          0x44DE
#define SHTC3_LM_CD_ReadTH          0x609C
#define SHTC3_LM_CD_ReadRH          0x401A
#define SHTC3_Software_RES          0x401A
#define SHTC3_ID                    0xEFC8

#define CRC_POLYNOMIAL              0x131 // P(x) = x^8 + x^5 + x^4 + 1 = 100110001

float TH_Value,RH_Value;
char checksum;
int fd;
char SDA = 8;
char SCL = 9;
char SHTC3_CheckCrc(char data[],unsigned char len,unsigned char checksum)
{
  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 < len; byteCtr++) {
    crc ^= (data[byteCtr]);
    for(bit = 8; bit > 0; --bit) {
      if(crc & 0x80) {
        crc = (crc << 1) ^ CRC_POLYNOMIAL;
      } else {
        crc = (crc << 1);
      }
    }
  }

  // verify checksum
  if(crc != checksum) {                 
    return 1;                       //Error
  } else {
    return 0;                       //No error
  }       
}
void SHTC3_WriteCommand(unsigned short cmd)
{   
    char buf[] = { (cmd>>8) ,cmd};
	write(fd,buf,2); 
}
void SHTC3_WAKEUP()
{     
    SHTC3_WriteCommand(SHTC3_WakeUp);                  // Write wake_up command  
    usleep(300);                          //Delay 300us
      
}
void SHTC3_SLEEP()
{    
 //   bcm2835_i2c_begin();
    SHTC3_WriteCommand(SHTC3_Sleep);                        // Write sleep command
      
}

void SHTC_SOFT_RESET()
{   
    SHTC3_WriteCommand(SHTC3_Software_RES);                 // Write reset command
    usleep(300);                                 //Delay 300us
     
}

void SHTC3_Read_DATA()
{   
    unsigned short TH_DATA,RH_DATA;
    char buf[3];
   SHTC3_WriteCommand(SHTC3_NM_CD_ReadTH);                 //Read temperature first, clock stretching disabled (polling)
    usleep(20000);
    read(fd, buf, 3);

   checksum=buf[2];
   if(!SHTC3_CheckCrc(buf,2,checksum))
        TH_DATA=(buf[0]<<8|buf[1]);
    
    SHTC3_WriteCommand(SHTC3_NM_CD_ReadRH);                 //Read temperature first, clock stretching disabled (polling)
    usleep(20000);
    read(fd, buf, 3);

    checksum=buf[2];
    if(!SHTC3_CheckCrc(buf,2,checksum))
        RH_DATA=(buf[0]<<8|buf[1]);
    
    TH_Value=175 * (float)TH_DATA / 65536.0f - 45.0f;       //Calculate temperature value
    RH_Value=100 * (float)RH_DATA / 65536.0f;              //Calculate humidity value  
    
}

int main()
{   
    printf("\n SHTC3 Sensor Test Program ...\n");
	fd = open(I2C_DEVICE, O_RDWR);
	if(fd < 0)
	{
		printf("Fail to open i2c device\r\n");
		return -1;
	}
	else
	{
		printf("Fopen : %s\r\n", I2C_DEVICE);
	}

	if(ioctl(fd, I2C_SLAVE, SHTC3_I2C_ADDRESS) < 0)
	{
		printf("I2C: Failed to connect to the device\n");
		return -1;
	}

    SHTC_SOFT_RESET();
    while (1)
    {
        SHTC3_Read_DATA();
        SHTC3_SLEEP();
        SHTC3_WAKEUP();

	    printf("Temperature = %6.2f°C , Humidity = %6.2f%% \r\n", TH_Value, RH_Value);
    }
    return 0;
}

sudo apt-get install gcc-riscv64-linux-gnu

riscv64-linux-gnu-gcc -o test-shtc3 test-shtc3.c

rsync ./test-shtc3 <User_Name>@<Board_IP_Address>:/home/riscv

信息：

• <User_Name>: 开发板的用户名。例如：riscv。
• <Board_IP_Address>: 开发板的IP地址。例如：192.168.92.133。

示例：

现在，我们已经成功读取了温度和湿度数据。