MAX32630FTHR板的学习（三）：MAX30102的初步使用及心率、血氧的测量原理

#include "mbed.h"

#include "max32630fthr.h"



#define false 0

#define true 1

MAX32630FTHR pegasus(MAX32630FTHR::VIO_3V3);

Serial pc(USBTX, USBRX);//USB TO SERIAL

DigitalIn INT(P3_2);  //pin P3.2 connects to the interrupt output pin of the MAX30102

I2C i2cm1(P3_4, P3_5);





#define I2C_WRITE_ADDR 0xAE

#define I2C_READ_ADDR 0xAF



//register addresses

#define REG_INTR_STATUS_1 0x00

#define REG_INTR_STATUS_2 0x01

#define REG_INTR_ENABLE_1 0x02

#define REG_INTR_ENABLE_2 0x03

#define REG_FIFO_WR_PTR 0x04

#define REG_OVF_COUNTER 0x05

#define REG_FIFO_RD_PTR 0x06

#define REG_FIFO_DATA 0x07

#define REG_FIFO_CONFIG 0x08

#define REG_MODE_CONFIG 0x09

#define REG_SPO2_CONFIG 0x0A

#define REG_LED1_PA 0x0C

#define REG_LED2_PA 0x0D

#define REG_PILOT_PA 0x10

#define REG_MULTI_LED_CTRL1 0x11

#define REG_MULTI_LED_CTRL2 0x12

#define REG_TEMP_INTR 0x1F

#define REG_TEMP_FRAC 0x20

#define REG_TEMP_CONFIG 0x21

#define REG_PROX_INT_THRESH 0x30

#define REG_REV_ID 0xFE

#define REG_PART_ID 0xFF



bool maxim_max30102_write_reg(uint8_t uch_addr, uint8_t uch_data)

/**

* \brief        Write a value to a MAX30102 register

* \par          Details

*               This function writes a value to a MAX30102 register

*

* \param[in]    uch_addr    - register address

* \param[in]    uch_data    - register data

*

* \retval       true on success

*/

{

  char ach_i2c_data[2];

  ach_i2c_data[0]=uch_addr;

  ach_i2c_data[1]=uch_data;

  

  if(i2cm1.write(I2C_WRITE_ADDR, ach_i2c_data, 2, false)==0)

    return true;

  else

    return false;

}



bool maxim_max30102_read_reg(uint8_t uch_addr, uint8_t *puch_data)

/**

* \brief        Read a MAX30102 register

* \par          Details

*               This function reads a MAX30102 register

*

* \param[in]    uch_addr    - register address

* \param[out]   puch_data    - pointer that stores the register data

*

* \retval       true on success

*/

{

  char ch_i2c_data;

  ch_i2c_data=uch_addr;

  if(i2cm1.write(I2C_WRITE_ADDR, &ch_i2c_data, 1, true)!=0)

    return false;

  if(i2cm1.read(I2C_READ_ADDR, &ch_i2c_data, 1, false)==0)

  {

    *puch_data=(uint8_t) ch_i2c_data;

    return true;

  }

  else

    return false;

}



bool maxim_max30102_reset()

/**

* \brief        Reset the MAX30102

* \par          Details

*               This function resets the MAX30102

*

* \param        None

*

* \retval       true on success

*/

{

    if(!maxim_max30102_write_reg(REG_MODE_CONFIG,0x40))

        return false;

    else

        return true;    

}



bool maxim_max30102_init()

/**

* \brief        Initialize the MAX30102

* \par          Details

*               This function initializes the MAX30102

*

* \param        None

*

* \retval       true on success

*/

{

  if(!maxim_max30102_write_reg(REG_INTR_ENABLE_1,0xc0)) // INTR setting

    return false;

  if(!maxim_max30102_write_reg(REG_INTR_ENABLE_2,0x02))

    return false;

  if(!maxim_max30102_write_reg(REG_FIFO_WR_PTR,0x00))  //FIFO_WR_PTR[4:0]

    return false;

  if(!maxim_max30102_write_reg(REG_OVF_COUNTER,0x00))  //OVF_COUNTER[4:0]

    return false;

  if(!maxim_max30102_write_reg(REG_FIFO_RD_PTR,0x00))  //FIFO_RD_PTR[4:0]

    return false;

  if(!maxim_max30102_write_reg(REG_FIFO_CONFIG,0x0f))  //sample avg = 1, fifo rollover=false, fifo almost full = 17

    return false;

  if(!maxim_max30102_write_reg(REG_MODE_CONFIG,0x03))   //0x02 for Red only, 0x03 for SpO2 mode 0x07 multimode LED

    return false;

  if(!maxim_max30102_write_reg(REG_SPO2_CONFIG,0x27))  // SPO2_ADC range = 4096nA, SPO2 sample rate (100 Hz), LED pulseWidth (400uS)

    return false;

  

  if(!maxim_max30102_write_reg(REG_LED1_PA,0x24))   //Choose value for ~ 7mA for LED1

    return false;

  if(!maxim_max30102_write_reg(REG_LED2_PA,0x24))   // Choose value for ~ 7mA for LED2

    return false;

  if(!maxim_max30102_write_reg(REG_PILOT_PA,0x7f))   // Choose value for ~ 25mA for Pilot LED

    return false;

if(!maxim_max30102_write_reg(REG_TEMP_CONFIG,0x01))   // En temp

    return false;

    

  return true;  

}



int main()

{

    uint8_t temp_inter,temp_fra;

    float temp_value;

    

    maxim_max30102_reset(); //resets the MAX30102

    // initialize serial communication at 9600 bits per second:

    pc.baud(9600);

    pc.format(8,SerialBase::None,1);

    pc.printf("ready to go!");

    wait(1);

    

    //read and clear status register

    maxim_max30102_read_reg(0,&temp_inter);

    maxim_max30102_init();

    

    while(1)

    {

    while(INT.read()==1);

    maxim_max30102_read_reg(REG_TEMP_INTR,&temp_inter);

    maxim_max30102_read_reg(REG_TEMP_FRAC,&temp_fra);

    temp_value=temp_inter+temp_fra*0.0625;

    pc.printf("temperature is %6.4f \n\r", temp_value);

    }

}