STM32F407-驱动SHT41采集温湿度

SHT41

SHT41通过I2C方式进行驱动

从机地址： 0x44

获取数据方式
1）先发送I2C写，写入特定指令
2）延时一段时间，等待SHT41处理
3）再进行I2C读，读数据即可

一些指令如下：
demo

STM32F407驱动

I2C初始化

void my_sht41_init()
{
	GPIO_InitTypeDef GPIO_InitStructure;
	I2C_InitTypeDef  I2C_InitStructure;
	
	RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB,ENABLE);  
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1,ENABLE); 
	
	GPIO_PinAFConfig(GPIOB,GPIO_PinSource8,GPIO_AF_I2C1);
	GPIO_PinAFConfig(GPIOB,GPIO_PinSource9,GPIO_AF_I2C1); 
	
	  
  GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;  
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;  
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8 | GPIO_Pin_9 ;  
  GPIO_Init(GPIOB, &GPIO_InitStructure);
	
	I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
	I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
	I2C_InitStructure.I2C_ClockSpeed = 300000;
	I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;
	I2C_InitStructure.I2C_OwnAddress1 = STM32_I2C_OWN_ADDR;	
	I2C_Init(I2C1, &I2C_InitStructure); 
	
	I2C_Cmd(I2C1, ENABLE);
	
}

读SHT41 芯片ID

void my_sht41_read_id(void)
{
	uint8_t data[6] = {0};
	uint8_t ret = 0;
	uint16_t time = 0xFFF;
	my_sht41_send_cmd(0x89);
	
	printf("开始延迟\n");
	while(time)
	{
		time--;
	}
	printf("延时结束\n");
	ret = my_SHT41_buffer_read(data,6);
	
	if(ret == 0)
	{
		printf("data[0] = 0x%x\n",data[0]);
		printf("data[1] = 0x%x\n",data[1]);
		printf("data[3] = 0x%x\n",data[3]);
		printf("data[4] = 0x%x\n",data[4]);
	}
	else
	{
		printf("读取ID错误!\n");
	}
	
}

读温度湿度数据

void my_sht41_read_data(void)
{
	uint8_t data[6] = {0};
	uint8_t ret = 0;
	uint32_t time = 0xFFFFFF;
	my_sht41_send_cmd(0xFD);
	
	uint16_t recovery_temper = 0u;
	uint16_t recovery_hum = 0u;
	float temp = 0.f;
	float hum = 0.f;
	
	
	printf("开始延迟\n");
	while(time)
	{
		time--;
	}
	printf("延时结束\n");
	ret = my_SHT41_buffer_read(data,6);
	
	if(ret == 0)
	{
		printf("data[0] = 0x%x\n",data[0]);
		printf("data[1] = 0x%x\n",data[1]);
		printf("data[3] = 0x%x\n",data[3]);
		printf("data[4] = 0x%x\n",data[4]);
	}
	else
	{
		printf("读取ID错误!\n");
	}
	
	recovery_temper = ((uint16_t)data[0]<<8)|data[1];
    temp = -45 + 175*((float)recovery_temper/65535);
 
    /* 转换湿度数据 */
    recovery_hum = ((uint16_t)data[3]<<8)|data[4];
    hum = -6 + 125 * ((float)recovery_hum / 65535);
		if(hum>=100)   //根据数据手册编写
				hum=100;
		else if(hum<=0)
				hum=0;
		
		printf("温度为：%.2f",temp);
		printf("湿度为：%.1f%%",hum);

	
}

I2C读写接口

static uint8_t my_sht41_send_cmd(uint8_t data)
{
	uint32_t count_wait;
	I2C_GenerateSTART(I2C1,ENABLE); 
	
	
	count_wait = TIME_OUT;
	while(I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_MODE_SELECT) != SUCCESS)
	{
		count_wait--;
		if(count_wait == 0) {
			return Error_CallBack(1);
		}
	}
	
	I2C_Send7bitAddress(I2C1, SHT41_I2C_ADDR, I2C_Direction_Transmitter); 
	

	
	count_wait = TIME_OUT;
	
	while(I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED) != SUCCESS)
	{
		count_wait--;
		if(count_wait == 0) {
			return Error_CallBack(2);
		}
	}
	
	

	//发送数据
	I2C_SendData(I2C1,data); 
	
	count_wait = TIME_OUT;
	while(I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_BYTE_TRANSMITTED) != SUCCESS)
	{
		count_wait--;
		if(count_wait == 0) {
			return Error_CallBack(4);
		}
	}	
	
	
	I2C_GenerateSTOP(I2C1, ENABLE);
	
	
	return 0;
	
}


/*读六个字节数据 */
static uint8_t my_SHT41_buffer_read(uint8_t *data,uint16_t size)
{
	uint32_t count_wait;
	//开始进行I2C通讯
	I2C_GenerateSTART(I2C1, ENABLE);
	
	if(size > 6)
	{
		return 1;
	}
	
	count_wait = TIME_OUT;	//等待拉低
	while(I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT) != SUCCESS)
	{
		count_wait--;
		if(count_wait == 0 )
		{
			return Error_CallBack(16);
		}
	}	
	
	//读模式
	I2C_Send7bitAddress(I2C1, SHT41_I2C_ADDR, I2C_Direction_Receiver);
	
	
	count_wait = TIME_OUT;
	while(I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED) != SUCCESS)
	{
		count_wait--;
		if(count_wait == 0 )
		{
			return Error_CallBack(20);
		}
	}
	
	while(size--)
	{
		if(size == 0)
		{
			I2C_AcknowledgeConfig(I2C1, DISABLE);
		}else {
			I2C_AcknowledgeConfig(I2C1,ENABLE);
		}

		count_wait = TIME_OUT;		
		while(I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED) != SUCCESS)
		{
			count_wait--;
			if(count_wait == 0 )
			{
				return Error_CallBack(21);
			}
		}
			
		
		*data = I2C_ReceiveData(I2C1);
		data++;
	}
	
		
	
	I2C_GenerateSTOP(I2C1, ENABLE);
	
	return 0;

}