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亮度传感器MAX44009 STM32模拟IIC驱动

2019-12-10 · 8 min read
STM32

MAX44009 driver for STM32 use software IIC

当前程序运行环境:STM32F103C8T6
IIC IO端口:PB10,PB11
ADDR端口连接至GND

IIC驱动文件:myiic.c

#include "myiic.h"
#include "delay.h"

//初始化IIC
void IIC_Init(void)
{			
    GPIO_InitTypeDef GPIO_InitStructure;
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB , ENABLE); //使能GPIOB时钟

    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10 | GPIO_Pin_11;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; //推挽输出
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOB, &GPIO_InitStructure);
    GPIO_SetBits(GPIOB, GPIO_Pin_10 | GPIO_Pin_11); //PB6,PB7 输出高,空闲状态
}
//产生IIC起始信号
void IIC_Start(void)
{
	SDA_OUT();     //sda线输出
	IIC_SDA=1;	  	  
	IIC_SCL=1;
	delay_us(4);
 	IIC_SDA=0;//START:when CLK is high,DATA change form high to low 
	delay_us(4);
	IIC_SCL=0;//钳住I2C总线,准备发送或接收数据 
}	  

void IIC_Stop(void)
{
	SDA_OUT();//sda线输出
	IIC_SDA=0;
 	IIC_SCL=1;
	delay_us(4);
	IIC_SDA=1;//发送I2C总线结束信号
	delay_us(4);							   	
}
//等待应答信号到来
//返回值:1,接收应答失败
//        0,接收应答成功
u8 IIC_Wait_Ack(void)
{
	u8 ucErrTime=0;
	SDA_IN();      //SDA设置为输入  
	IIC_SDA=1;delay_us(1);	   
	IIC_SCL=1;delay_us(1);	 
	while(READ_SDA)
	{
		ucErrTime++;
		if(ucErrTime>250)
		{
			IIC_Stop();
			return 1;
		}
	}
	IIC_SCL=0;//时钟输出0 	   
	return 0;  
} 
//产生ACK应答
void IIC_Ack(void)
{
	IIC_SCL=0;
	SDA_OUT();
	IIC_SDA=0;
	delay_us(2);
	IIC_SCL=1;
	delay_us(2);
	IIC_SCL=0;
}
//不产生ACK应答		    
void IIC_NAck(void)
{
	IIC_SCL=0;
	SDA_OUT();
	IIC_SDA=1;
	delay_us(2);
	IIC_SCL=1;
	delay_us(2);
	IIC_SCL=0;
}					 				     
//IIC发送一个字节
//返回从机有无应答
//1,有应答
//0,无应答			  
void IIC_Send_Byte(u8 txd)
{                        
    u8 t;   
	SDA_OUT(); 	    
    IIC_SCL=0;//拉低时钟开始数据传输
    for(t=0;t<8;t++)
    {              
        IIC_SDA=(txd&0x80)>>7;
        txd<<=1; 	  
		delay_us(2);   //对TEA5767这三个延时都是必须的
		IIC_SCL=1;
		delay_us(2); 
		IIC_SCL=0;	
		delay_us(2);
    }	 
} 	    
//读1个字节,ack=1时,发送ACK,ack=0,发送nACK   
u8 IIC_Read_Byte(unsigned char ack)
{
	unsigned char i,receive=0;
	SDA_IN();//SDA设置为输入
    for(i=0;i<8;i++ )
	{
        IIC_SCL=0; 
        delay_us(2);
		IIC_SCL=1;
        receive<<=1;
        if(READ_SDA)receive++;   
		delay_us(2); 
    }					 
    if (!ack)
        IIC_NAck();//发送nACK
    else
        IIC_Ack(); //发送ACK   
    return receive;
}


IIC驱动文件:myiic.h

#ifndef __MYIIC_H
#define __MYIIC_H
#include "sys.h" 
   	   		   
//IO方向设置
#define SDA_IN()  {GPIOB->CRH &= 0xFFFF0FFF;GPIOB->CRH |= 0x00008000;}	//PB11输入模式
#define SDA_OUT() {GPIOB->CRH &= 0xFFFF0FFF;GPIOB->CRH |= 0x00003000;} //PB11输出模式
//IO操作函数	 
#define IIC_SCL    PBout(10) //SCL
#define IIC_SDA    PBout(11) //SDA	 
#define READ_SDA   PBin(11)  //输入SDA 

//IIC所有操作函数
void IIC_Init(void);                //初始化IIC的IO口				 
void IIC_Start(void);				//发送IIC开始信号
void IIC_Stop(void);	  			//发送IIC停止信号
void IIC_Send_Byte(u8 txd);			//IIC发送一个字节
u8 IIC_Read_Byte(unsigned char ack);//IIC读取一个字节
u8 IIC_Wait_Ack(void); 				//IIC等待ACK信号
void IIC_Ack(void);					//IIC发送ACK信号
void IIC_NAck(void);				//IIC不发送ACK信号

void IIC_Write_One_Byte(u8 daddr,u8 addr,u8 data);
u8 IIC_Read_One_Byte(u8 daddr,u8 addr);	  
#endif

MAX44009驱动文件:MAX44009.c

#include "MAX44009.h"
#include "myiic.h"
#include "delay.h"

void MAX44009_Init(void)
{

	IIC_Init(); //IIC初始化
	MAX44009_WriteOneByte(MAX44009_REG_CFG, 0x03);				// Default mode: measurements performed every 800ms
																// Auto range: CDR and integration time are automatically determined by
																//             the internal autoranging circuitry of the IC
	MAX44009_WriteOneByte(MAX44009_REG_INTE, MAX44009_INT_DISABLE);//关闭中断
	MAX44009_WriteOneByte(MAX44009_REG_THT, MAX44009_IT_800ms);//积分时间800ms
	MAX44009_WriteOneByte(MAX44009_REG_THU, 0xff);
	MAX44009_WriteOneByte(MAX44009_REG_THL, 0x00);
	MAX44009_WriteOneByte(0x02,0x80);//连续转换、手动模式、积分时间6.25MS
}

//在MAX44009指定地址读出一个数据
//ReadAddr:开始读数的地址
//返回值  :读到的数据
u8 MAX44009_ReadOneByte(u8 ReadAddr)
{
	u8 temp = 0;
	IIC_Start();

	IIC_Send_Byte(MAX44009_ADDR);
	IIC_Wait_Ack();

	IIC_Send_Byte(ReadAddr);
	IIC_Wait_Ack();

	IIC_Start();
	IIC_Send_Byte(MAX44009_ADDR+1); //进入接收模式
	IIC_Wait_Ack();

	temp = IIC_Read_Byte(0);

	IIC_Stop(); //产生一个停止条件
	return temp;
}
//在MAX44009指定地址写入一个数据
//WriteAddr  :写入数据的目的地址
//DataToWrite:要写入的数据
void MAX44009_WriteOneByte(u8 WriteAddr, u8 DataToWrite)
{
	IIC_Start();
	IIC_Send_Byte(MAX44009_ADDR);
	IIC_Wait_Ack();

	IIC_Send_Byte(WriteAddr);
	IIC_Wait_Ack();

	IIC_Send_Byte(DataToWrite); //发送字节
	IIC_Wait_Ack();

	IIC_Stop(); //产生一个停止条件
}

//在MAX44009里面读取流明值

float MAX44009_ReadLux(void)
{
	u8 exponent=0, mantissa=0;
	u8 High_Lux = 0, Low_Lux = 0;
	float result=0;
	High_Lux=MAX44009_ReadOneByte(0x03);
	Low_Lux=MAX44009_ReadOneByte(0x04);
	
	exponent = (High_Lux & 0xF0) >> 4;
	mantissa = (High_Lux & 0x0F) << 4;
	mantissa += Low_Lux & 0x0F;
	result=(float)(((0x00000001 << exponent) * (float)mantissa) * 0.045);
	return result;
}
//在MAX44009里面的指定地址开始写入长度为Len的数据
//该函数用于写入16bit或者32bit的数据.
//WriteAddr  :开始写入的地址
//DataToWrite:数据数组首地址
//Len        :要写入数据的长度2,4
void MAX44009_WriteLenByte(u16 WriteAddr, u32 DataToWrite, u8 Len)
{
	u8 t;
	for (t = 0; t < Len; t++)
	{
		MAX44009_WriteOneByte(WriteAddr + t, (DataToWrite >> (8 * t)) & 0xff);
	}
}

//在MAX44009里面的指定地址开始读出长度为Len的数据
//该函数用于读出16bit或者32bit的数据.
//ReadAddr   :开始读出的地址
//返回值     :数据
//Len        :要读出数据的长度2,4
u32 MAX44009_ReadLenByte(u16 ReadAddr, u8 Len)
{
	u8 t;
	u32 temp = 0;
	for (t = 0; t < Len; t++)
	{
		temp <<= 8;
		temp += MAX44009_ReadOneByte(ReadAddr + Len - t - 1);
	}
	return temp;
}

//在MAX44009里面的指定地址开始读出指定个数的数据
//ReadAddr :开始读出的地址
//pBuffer  :数据数组首地址
//NumToRead:要读出数据的个数
void MAX44009_Read(u16 ReadAddr, u8 *pBuffer, u16 NumToRead)
{
	while (NumToRead)
	{
		*pBuffer++ = MAX44009_ReadOneByte(ReadAddr++);
		NumToRead--;
	}
}
//在MAX44009里面的指定地址开始写入指定个数的数据
//WriteAddr :开始写入的地址
//pBuffer   :数据数组首地址
//NumToWrite:要写入数据的个数
void MAX44009_Write(u16 WriteAddr, u8 *pBuffer, u16 NumToWrite)
{
	while (NumToWrite--)
	{
		MAX44009_WriteOneByte(WriteAddr, *pBuffer);
		WriteAddr++;
		pBuffer++;
	}
}

MAX44009驱动文件:MAX44009.h

#ifndef __MAX44009_H
#define __MAX44009_H
#include "sys.h"

// Accuracy of the Lux value calculation
//   0: reduced accuracy (slightly faster)
//   1: maximum accuracy (slightly slower)
#define MAX44009_ACCURACY 1

// MAX44009 HAL
#define MAX44009_I2C_PORT I2C1 // I2C port where the MAX44009 connected

// Possible I2C device addresses
#define MAX44009_ADDR_G ((uint8_t)0x4A) // A0 pin tied to GND //0100 1010
#define MAX44009_ADDR_V ((uint8_t)0x4B) // A0 pin tied to VCC //0100 1011

// Current I2C device address (depends on the pin A0 connection)
#define MAX44009_ADDR (MAX44009_ADDR_G << 1)
//#define MAX44009_ADDR (0x94)
// MAX44009 register definitions
#define MAX44009_REG_INTS ((uint8_t)0x00) // Interrupt status
#define MAX44009_REG_INTE ((uint8_t)0x01) // Interrupt enable
#define MAX44009_REG_CFG ((uint8_t)0x02)  // Configuration
#define MAX44009_REG_LUXH ((uint8_t)0x03) // Lux reading high byte
#define MAX44009_REG_LUXL ((uint8_t)0x04) // Lux reading low byte
#define MAX44009_REG_THU ((uint8_t)0x05)  // Upper threshold high byte
#define MAX44009_REG_THL ((uint8_t)0x06)  // Lower threshold high byte
#define MAX44009_REG_THT ((uint8_t)0x07)  // Threshold timer

// MAX44009 interrupt status end configuration definitions
#define MAX44009_INT_SET ((uint8_t)0x01)     // Interrupt is asserted
#define MAX44009_INT_RESET ((uint8_t)0x00)   // Interrupt is deasserted
#define MAX44009_INT_ENABLE ((uint8_t)0x01)  // Interrupt enabled
#define MAX44009_INT_DISABLE ((uint8_t)0x00) // Interrupt disabled

// MAX44009 CFG register bits

#define MAX44009_CFG_CONT ((uint8_t)0x80)   // Continuous mode
#define MAX44009_CFG_MANUAL ((uint8_t)0x40) // Manual configuration

// Current division ratio (CDR)
#define MAX44009_CDR_NORM ((uint8_t)0x00) // All photodiode current goes to the ADC
#define MAX44009_CDR_DIV8 ((uint8_t)0x08) // Only 1/8 of the photodiode current goes to the ADC

// Integration time
#define MAX44009_IT_800ms ((uint8_t)0x00)  // 800ms
#define MAX44009_IT_400ms ((uint8_t)0x01)  // 400ms
#define MAX44009_IT_200ms ((uint8_t)0x02)  // 200ms
#define MAX44009_IT_100ms ((uint8_t)0x03)  // 100ms
#define MAX44009_IT_50ms ((uint8_t)0x04)   // 50ms
#define MAX44009_IT_25ms ((uint8_t)0x05)   // 25ms
#define MAX44009_IT_12d5ms ((uint8_t)0x06) // 12.5ms
#define MAX44009_IT_6d25ms ((uint8_t)0x07) // 6.25ms

// Bit mask for MODE and RANGE bits
#define MAX44009_MASK_CFG_MODE ((uint8_t)0xC0)

// Bit mask for CDR bit and integration time
#define MAX44009_MASK_CDR_IT ((uint8_t)0x0F)

// Value indicating overrange condition (used in return of GetLux() function)
#define MAX44009_OVERRANGE ((uint32_t)1000000000U)

void MAX44009_Init(void);
u8 MAX44009_ReadOneByte(u8 ReadAddr);
void MAX44009_WriteOneByte(u8 WriteAddr,u8 DataToWrite);
void MAX44009_WriteLenByte(u16 WriteAddr,u32 DataToWrite,u8 Len);
u32 MAX44009_ReadLenByte(u16 ReadAddr,u8 Len);
void MAX44009_Read(u16 ReadAddr,u8 *pBuffer,u16 NumToRead);
void MAX44009_Write(u16 WriteAddr,u8 *pBuffer,u16 NumToWrite);
float MAX44009_ReadLux(void);

#endif