基于STM32CUBEIDE SHT31温湿度传感器温湿度获取

jiangyy · 发表于 2020-11-23 10:54:37

直接上代码

/*
* bsp_sht31_1.c
*
* Created on: 2020年11月10日
* Author: jiangyuanyuan
*/
#include "bsp_sht31_1.h"
void SHT31_SDA_IN(void)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
//PB7初始化设置
SHT7_DIR_BA();
GPIO_InitStruct.Pin = SHT7_SDA1_Pin;
GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
GPIO_InitStruct.Pull = GPIO_PULLUP;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
}
void SHT31_SDA_OUT(void)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
//PB7初始化设置
SHT7_DIR_AB();
GPIO_InitStruct.Pin = SHT7_SDA1_Pin;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Pull = GPIO_PULLUP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
}
/*************************以下为IO口模拟IIC通信**********************************/
//IIC起始信号
void SHT31_Start(void)
{
//when scl is high, the SDA is change from high to low
SHT31_SDA_OUT(); //配置SDA线为输出
SHT31_IIC_SDAOUT = 1;
// Delay_us(5);
SHT31_IIC_SCL = 1;
Delay_us(10);
SHT31_IIC_SDAOUT = 0;
Delay_us(10);
SHT31_IIC_SCL = 0; //准备发送或接收数据
Delay_us(10);
}
//IIC停止信号
void SHT31_Stop(void)
{
//When scl is high， the SDA is change from low to high
SHT31_SDA_OUT(); //配置SDA线为输出
SHT31_IIC_SCL = 0;
Delay_us(3);
SHT31_IIC_SDAOUT = 0;
Delay_us(5);
SHT31_IIC_SCL = 1;
Delay_us(10);
SHT31_IIC_SDAOUT = 1; //发送I2C总线结束信号
Delay_us(10);
}
/****************************************************************************
* 名称: u8 MCU_Wait_Ack(void)
* 功能：MCU等待从设备应答信号到来
* 入口参数：无
* 返回参数：1:接收应答失败 0:接收应答成功
* 说明： 
****************************************************************************/
u8 SHT31_Wait_Ack(void)
{
u16 WaitTime = 0;
SHT31_IIC_SDAOUT = 1;
SHT31_SDA_IN(); //配置SDA线为输入
Delay_us(4); //2
SHT31_IIC_SCL = 1;
Delay_us(2); //5
while(SHT31_IIC_SDAIN)
{
Delay_us(1);
WaitTime++;
if(WaitTime>250)
{
SHT31_Stop();
return 1;
}
}
SHT31_IIC_SCL = 0;
Delay_us(8); //added
return 0;
}
/****************************************************************************
* 名称: u8 void MCU_Send_Ack(void)
* 功能：MCU产生ACK应答,告知24cxx
* 入口参数：无
* 返回参数：
* 说明： 
****************************************************************************/
void SHT31_Send_Ack(void)
{
SHT31_IIC_SCL = 0;
SHT31_SDA_OUT();
SHT31_IIC_SDAOUT = 0;
Delay_us(2);
SHT31_IIC_SCL = 1;
Delay_us(2);
SHT31_IIC_SCL = 0;
}
/****************************************************************************
* 名称: u8 void MCU_Send_Ack(void)
* 功能：MCU不产生ACK应答
* 入口参数：无
* 返回参数：
* 说明： 
****************************************************************************/
void SHT31_NOAck(void)
{
SHT31_IIC_SCL = 0;
SHT31_SDA_OUT();
SHT31_IIC_SDAOUT = 1;
Delay_us(2);
SHT31_IIC_SCL = 1;
Delay_us(2);
SHT31_IIC_SCL = 0;
}
/****************************************************************************
* 名称: void IIC_write_OneByte(u8 Senddata)
* 功能：IIC写一个字节到EEPROM
* 入口参数：Senddata:写入的8位数据
* 返回参数：
* 说明： 
****************************************************************************/
void SHT31_write_OneByte(u8 Senddata)
{
u8 t;
SHT31_SDA_OUT();
// IIC_SCL=0; //拉低时钟开始数据传输
for(t = 0;t < 8;t++)
{
SHT31_IIC_SDAOUT=(Senddata&0x80)>>7;
Senddata <<= 1;
Delay_us(5);
SHT31_IIC_SCL = 1;
Delay_us(10);
SHT31_IIC_SCL = 0;
Delay_us(2);
}
}
/****************************************************************************
* 名称: void IIC_Read_OneByte(u8 Senddata)
* 功能：IIC读取一个字节
* 入口参数：ack=1，发送ACK，ack=0，发送nACK
* 返回参数：读到的8位数据
* 说明： 
****************************************************************************/
u8 SHT31_Read_OneByte(u8 ack)
{
u8 i,receivedata = 0;
SHT31_SDA_IN(); //配置SDA线为输入
for(i=0;i<8;i++ )
{
SHT31_IIC_SCL = 0;
Delay_us(3);
SHT31_IIC_SCL = 1;
Delay_us(5); //added by xiang
receivedata <<= 1;
if(SHT31_IIC_SDAIN)
receivedata++;
Delay_us(1);
}
if (!ack)
SHT31_NOAck();//发送nACK
else
SHT31_Send_Ack(); //发送ACK
return receivedata;
}
//初始化IIC接口
void SHT31_Init(void)
{
Delay_us(200);
SHT31_SetPeriodicMeasurement();
Delay_us(200);
}
u16 TemValue = 0;
u16 RhValue = 0;
u8 Flag_New_Data = 0;
void SHT31_Get(void)
{
u16 temp1 = 0,temp2 = 0;
u16 data;
u8 buf1[3],buf2[3]; //store Temperature +crc and Humidity +crc
SHT31_Start(); //启动总线
SHT31_write_OneByte(i2cAddWrite_8bit); //发送写命令(i2c地址）
SHT31_Wait_Ack(); //等待应答
SHT31_write_OneByte(CMD_FETCH_DATA_H); //发送地址 High
SHT31_Wait_Ack(); //等待应答
SHT31_write_OneByte(CMD_FETCH_DATA_L); //发送地址 Low
SHT31_Wait_Ack(); //等待应答
SHT31_Start(); //重新启动总线
SHT31_write_OneByte(i2cAddRead_8bit); //设置为读操作
SHT31_Wait_Ack(); //等待应答;
//读字节下面连续读出数据6 bytes 前5个ACK应答最后一个NO ACK
buf1[0] = SHT31_Read_OneByte(1);
buf1[1] = SHT31_Read_OneByte(1);
buf1[2] = SHT31_Read_OneByte(1);
buf2[0] = SHT31_Read_OneByte(1);
buf2[1] = SHT31_Read_OneByte(1);
buf2[2] = SHT31_Read_OneByte(0);
SHT31_Stop(); //结束总线
temp1 = SHT31_CheckCrc(buf1,2,buf1[2]);
if(!temp1)
{
data = (buf1[0]<<8)|buf1[1];
TemValue = SHT31_CalcTemperature(data);
Flag_New_Data = 1;
}
temp2 = SHT31_CheckCrc(buf2,2,buf2[2]);
if(!temp2)
{
data = (buf2[0]<<8) | buf2[1];
RhValue = SHT31_CalcRH(data);
Flag_New_Data = 1;
}
*(u16 *)&ucParamMem[ID_EMT][0] = TemValue;
*(u16 *)&ucParamMem[ID_EMH][0] = RhValue;
}
/******************************************************/
void SHT31_WriteCMD(u16 cmd)
{
SHT31_Start();
SHT31_write_OneByte(i2cAddWrite_8bit);
SHT31_Wait_Ack();
SHT31_write_OneByte(cmd>>8);
SHT31_Wait_Ack();
SHT31_write_OneByte(cmd);
SHT31_Wait_Ack();
SHT31_Stop();
}
/********************************************************/
void SHT31_SetPeriodicMeasurement(void)
{
SHT31_WriteCMD(CMD_MEAS_PERI_2_H);
}
u8 SHT31_CalcCrc(u8 *data, u8 nbrOfBytes)
{
u8 bit; // bit mask
u8 crc = 0xFF; // calculated checksum
u8 byteCtr; // byte counter
// calculates 8-Bit checksum with given polynomial
for(byteCtr = 0; byteCtr < nbrOfBytes; byteCtr++)
{
crc ^= (data[byteCtr]);
for(bit = 8; bit > 0; --bit)
{
if(crc & 0x80)
{
crc = (crc << 1) ^ POLYNOMIAL;
}
else
{
crc = (crc << 1);
}
}
}
return crc;
}
//校验
u8 SHT31_CheckCrc(u8 *pdata, u8 nbrOfBytes, u8 checksum)
{
u8 crc;
crc = SHT31_CalcCrc(pdata, nbrOfBytes);// calculates 8-Bit checksum
if(crc != checksum)
{
return 1;
}
return 0;
}
//获取温度
u16 SHT31_CalcTemperature(u16 rawValue)
{
// calculate temperature
u16 temp;
temp = (175 * (float)rawValue * 100 / 65535 - 4500) ; // T = -45 + 175 * rawValue / (2^16-1)
return temp;
}
//获取湿度
u16 SHT31_CalcRH(u16 rawValue)
{
// calculate relative humidity [%RH]
u16 temp = (100 * (float)rawValue * 100 / 65535) ; // RH = rawValue / (2^16-1) * 10
return temp;
}