AHT20温度传感器使用程序：

使用i2c读取温度传感器数据很简单，但市面上有至少两个手册，我这个对应的手册贴出来：

main:

#include "stm32f10x.h"                  // Device header
#include <stdint.h>
#include "delay.h"
#include "OLED.h"
#include "MPU6050.h"
#include "AHT20.h"
#include "serial.h"
#include "i2c.h"
#include "Delay.h"int16_t AX,AY,AZ,GX,GY,GZ;int count=0;
uint8_t ReceiveData=0,ReceiveData1=0;uint32_t arr[6]={0};uint32_t H1=0,T1=0;
int main (void)
{Serial_USART1_Init();printf("begin\r\n");I2C_GPIO_Init();OLED_Init();//AHT20Init();//AHT20_Begin_Measure();I2C_Start();I2C_Send_DataByte(0x71);I2C_Receive_Ack();ReceiveData=I2C_Read_DataByte();if((ReceiveData&0x08)==0x08){printf("success\r\n");}else{printf("failed\r\n");}/*开启测量*/I2C_Start();I2C_Send_DataByte(0x70);I2C_Receive_Ack();I2C_Send_DataByte(0xAC);I2C_Receive_Ack();I2C_Send_DataByte(0x33);I2C_Receive_Ack();I2C_Send_DataByte(0x00);I2C_Receive_Ack();I2C_Stop();Delay_ms(210);I2C_Start();I2C_Send_DataByte(0x71);I2C_Receive_Ack();ReceiveData1=I2C_Read_DataByte();if((ReceiveData1&0x80)==0x00){printf("completed\r\n");}else{printf("uncompleted\r\n");}I2C_Send_Ack(0);arr[0]=I2C_Read_DataByte();//humI2C_Send_Ack(0);arr[1]=I2C_Read_DataByte();//tempI2C_Send_Ack(0);arr[2]=I2C_Read_DataByte();//湿度+温度I2C_Send_Ack(0);arr[3]=I2C_Read_DataByte();//tempI2C_Send_Ack(1);I2C_Stop();H1=arr[0];H1=(H1<<8)|arr[1];H1=(H1<<8)|arr[2];H1=H1>>4;H1=H1*1000/1024/1024;printf("H1=%d\r\n",H1);printf("H1=%d%d.%d\r\n",H1/100,(H1/10)%10,H1%10);T1=arr[2];T1=T1&0x0000000F;T1=T1<<8;T1=T1|arr[3];T1=T1<<8;T1=T1|arr[4];T1=(T1*2000/1024/1024-500);//printf("T1=%d",T1);printf("T1=%d%d.%d",T1/100,T1/10%10,T1%10);OLED_ShowString(1,1,"str");while(1){MPU6050_Get_Data(&AX);//printf("%d\r\n",AX);OLED_ShowSignedNum(3,1,count,2);OLED_ShowSignedNum(2,1,AX,10);count++;}}

AHT20.c:

#include "stm32f10x.h"                  // Device header
#include "delay.h"
#include "i2c.h"
#include <stdint.h>
#include "AHT20.h"
#define Dev_Addr 0x70
#define Command1 0xAC
#define Command2 0x33
#define Command3 0x00//开启测量
void AHT20_Begin_Measure(){I2C_Start();I2C_Send_DataByte(Dev_Addr);//0x70I2C_Receive_Ack();I2C_Send_DataByte(Command1);//0xACI2C_Receive_Ack();I2C_Send_DataByte(Command2);//0x33I2C_Receive_Ack();I2C_Send_DataByte(Command3);//0x00I2C_Receive_Ack();I2C_Stop();Delay_ms(150);}void AHT20Init(){//AHT20Reset();I2C_Start();I2C_Send_DataByte(0x71);I2C_Receive_Ack();I2C_Send_DataByte(0xbe);I2C_Receive_Ack();I2C_Send_DataByte(0x08);I2C_Receive_Ack();I2C_Send_DataByte(0x00);I2C_Receive_Ack();I2C_Stop();}void AHT20Reset(){I2C_Start();I2C_Send_DataByte(0x70);I2C_Receive_Ack();I2C_Send_DataByte(0xBA);I2C_Receive_Ack();I2C_Stop();
}uint8_t AHT20_Read_State_Field(){uint8_t StateDataReceive=0;I2C_Start();I2C_Send_DataByte((Dev_Addr|0x01));I2C_Receive_Ack();StateDataReceive=I2C_Read_DataByte();return StateDataReceive;
}

i2c.c:

#include "stm32f10x.h"                  // Device header
#include "delay.h"void I2C_GPIO_Init(){RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);GPIO_InitTypeDef GPIO_InitStructure;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_OD;//开漏输出GPIO_InitStructure.GPIO_Pin=GPIO_Pin_10|GPIO_Pin_11;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init(GPIOB, &GPIO_InitStructure);	 	GPIO_SetBits(GPIOB,GPIO_Pin_10|GPIO_Pin_11);//设置引脚为高电平
}void I2C_W_SCL(uint8_t BitValue){GPIO_WriteBit(GPIOB,GPIO_Pin_10,(BitAction)BitValue);        Delay_us(10);
}void I2C_W_SDA(uint8_t BitValue){GPIO_WriteBit(GPIOB,GPIO_Pin_11,(BitAction)BitValue);Delay_us(10);
}void I2C_Start(){I2C_W_SCL(1);I2C_W_SDA(1);Delay_us(10); //高电平保持20msI2C_W_SDA(0);Delay_us(10);I2C_W_SCL(0);Delay_us(10);        
}void I2C_Stop(){I2C_W_SCL(0);I2C_W_SDA(0);Delay_us(10);I2C_W_SCL(1);    Delay_us(10);I2C_W_SDA(1);}void I2C_Receive_Ack(){I2C_W_SCL(0);//进入置SCL=0Delay_us(10);I2C_W_SDA(1);I2C_W_SCL(1);Delay_us(10);I2C_W_SCL(0);Delay_us(10);    
}void I2C_Send_Ack(uint8_t SendAckValue){I2C_W_SCL(0);if(SendAckValue==0){I2C_W_SDA(0);}I2C_W_SCL(1);Delay_us(10);I2C_W_SCL(0);            
}void I2C_Send_DataByte(uint8_t DataSend){uint8_t finger=0x80;I2C_W_SCL(0);//进入置SCL=0;Delay_us(10);for(uint8_t k=0;k<8;k++){if(DataSend&finger){I2C_W_SDA(1);Delay_us(10);}else{I2C_W_SDA(0);Delay_us(10);}I2C_W_SCL(1);Delay_us(10);I2C_W_SCL(0);Delay_us(10);        finger=finger>>1;}
}   uint8_t I2C_Read_DataByte(){//读取8位数据uint8_t DataReceive=0x00;uint8_t finger=0x80;I2C_W_SCL(0);//进入置SCL=0;I2C_W_SDA(1);//考虑设置为浮空，详见AHT20收藏Delay_us(10);for(uint8_t k=0;k<8;k++){I2C_W_SCL(1);Delay_us(10);if(GPIO_ReadInputDataBit(GPIOB,GPIO_Pin_11)==1){DataReceive=DataReceive|(finger>>k);            }else{//不操作}I2C_W_SCL(0);Delay_us(10);}return DataReceive;    
}uint8_t I2C_R_SDA(){uint8_t BitValue=0;BitValue=GPIO_ReadInputDataBit(GPIOB,GPIO_Pin_11);Delay_us(10);return BitValue;
}