Bradley Kohler / Mbed OS PulseRate

MAX30100 pulse rate sensor

Dependencies:   PulseRate

Dependents:   PulseRate

MAX30100.h@2:d329886938f1, 2017-08-23 (annotated)

Committer:
kohlerba
Date:
Wed Aug 23 19:04:51 2017 +0000
Revision:
2:d329886938f1
Parent:
1:0c2135629097
Child:
3:fa37b0c705b3
Updated

Who changed what in which revision?

UserRevisionLine numberNew contents of line
kohlerba 0:faf977308bdc 1 #ifndef MAX30100_H
kohlerba 0:faf977308bdc 2 #define MAX30100_H
kohlerba 0:faf977308bdc 3
kohlerba 0:faf977308bdc 4 #include "mbed.h"
kohlerba 0:faf977308bdc 5
kohlerba 0:faf977308bdc 6 //definitions
kohlerba 0:faf977308bdc 7 #define MAX30100_ADDRESS 0x57
kohlerba 0:faf977308bdc 8
kohlerba 0:faf977308bdc 9 // Registers
kohlerba 0:faf977308bdc 10 #define MAX30100_INT_STATUS 0x00 // Which interrupts are tripped
kohlerba 0:faf977308bdc 11 #define MAX30100_INT_ENABLE 0x01 // Which interrupts are active
kohlerba 0:faf977308bdc 12 #define MAX30100_FIFO_WR_PTR 0x02 // Where data is being written
kohlerba 0:faf977308bdc 13 #define MAX30100_OVRFLOW_CTR 0x03 // Number of lost samples
kohlerba 0:faf977308bdc 14 #define MAX30100_FIFO_RD_PTR 0x04 // Where to read from
kohlerba 0:faf977308bdc 15 #define MAX30100_FIFO_DATA 0x05 // Ouput data buffer
kohlerba 0:faf977308bdc 16 #define MAX30100_MODE_CONFIG 0x06 // Control register
kohlerba 0:faf977308bdc 17 #define MAX30100_SPO2_CONFIG 0x07 // Oximetry settings
kohlerba 0:faf977308bdc 18 #define MAX30100_LED_CONFIG 0x09 // Pulse width and power of LEDs
kohlerba 0:faf977308bdc 19 #define MAX30100_TEMP_INTG 0x16 // Temperature value, whole number
kohlerba 0:faf977308bdc 20 #define MAX30100_TEMP_FRAC 0x17 // Temperature value, fraction
kohlerba 0:faf977308bdc 21 #define MAX30100_REV_ID 0xFE // Part revision
kohlerba 0:faf977308bdc 22 #define MAX30100_PART_ID 0xFF // Part ID, normally 0x11
kohlerba 0:faf977308bdc 23
kohlerba 2:d329886938f1 24 #define POR_PART_ID 0x11
kohlerba 2:d329886938f1 25
kohlerba 0:faf977308bdc 26 typedef enum{ // This is the same for both LEDs
kohlerba 0:faf977308bdc 27 pw200, // 200us pulse
kohlerba 0:faf977308bdc 28 pw400, // 400us pulse
kohlerba 0:faf977308bdc 29 pw800, // 800us pulse
kohlerba 0:faf977308bdc 30 pw1600 // 1600us pulse
kohlerba 0:faf977308bdc 31 }pulseWidth;
kohlerba 0:faf977308bdc 32
kohlerba 0:faf977308bdc 33 typedef enum{
kohlerba 0:faf977308bdc 34 sr50, // 50 samples per second
kohlerba 0:faf977308bdc 35 sr100, // 100 samples per second
kohlerba 0:faf977308bdc 36 sr167, // 167 samples per second
kohlerba 0:faf977308bdc 37 sr200, // 200 samples per second
kohlerba 0:faf977308bdc 38 sr400, // 400 samples per second
kohlerba 0:faf977308bdc 39 sr600, // 600 samples per second
kohlerba 0:faf977308bdc 40 sr800, // 800 samples per second
kohlerba 0:faf977308bdc 41 sr1000 // 1000 samples per second
kohlerba 0:faf977308bdc 42 }sampleRate;
kohlerba 0:faf977308bdc 43
kohlerba 0:faf977308bdc 44 typedef enum{
kohlerba 0:faf977308bdc 45 i0, // No current
kohlerba 0:faf977308bdc 46 i4, // 4.4mA
kohlerba 0:faf977308bdc 47 i8, // 7.6mA
kohlerba 0:faf977308bdc 48 i11, // 11.0mA
kohlerba 0:faf977308bdc 49 i14, // 14.2mA
kohlerba 0:faf977308bdc 50 i17, // 17.4mA
kohlerba 0:faf977308bdc 51 i21, // 20.8mA
kohlerba 0:faf977308bdc 52 i27, // 27.1mA
kohlerba 0:faf977308bdc 53 i31, // 30.6mA
kohlerba 0:faf977308bdc 54 i34, // 33.8mA
kohlerba 0:faf977308bdc 55 i37, // 37.0mA
kohlerba 0:faf977308bdc 56 i40, // 40.2mA
kohlerba 0:faf977308bdc 57 i44, // 43.6mA
kohlerba 0:faf977308bdc 58 i47, // 46.8mA
kohlerba 0:faf977308bdc 59 i50 // 50.0mA
kohlerba 0:faf977308bdc 60 }ledCurrent;
kohlerba 0:faf977308bdc 61
kohlerba 0:faf977308bdc 62 //Set up I2C, (SDA,SCL)
kohlerba 0:faf977308bdc 63 I2C i2c(I2C_SDA, I2C_SCL);
kohlerba 0:faf977308bdc 64
kohlerba 0:faf977308bdc 65 uint16_t IR = 0; // Last IR reflectance datapoint
kohlerba 0:faf977308bdc 66 uint16_t RED = 0; // Last Red reflectance datapoint
kohlerba 0:faf977308bdc 67
kohlerba 0:faf977308bdc 68 class MAX30100 {
kohlerba 0:faf977308bdc 69
kohlerba 0:faf977308bdc 70 protected:
kohlerba 0:faf977308bdc 71
kohlerba 0:faf977308bdc 72 public:
kohlerba 0:faf977308bdc 73
kohlerba 2:d329886938f1 74 //Wire read and write protocols
kohlerba 0:faf977308bdc 75 void writeByte(uint8_t address, uint8_t subAddress, uint8_t data)
kohlerba 0:faf977308bdc 76 {
kohlerba 0:faf977308bdc 77 char data_write[2];
kohlerba 0:faf977308bdc 78 data_write[0] = subAddress;
kohlerba 0:faf977308bdc 79 data_write[1] = data;
kohlerba 0:faf977308bdc 80 i2c.write(address, data_write, 2, 0);
kohlerba 0:faf977308bdc 81 }
kohlerba 0:faf977308bdc 82
kohlerba 0:faf977308bdc 83 char readByte(uint8_t address, uint8_t subAddress)
kohlerba 0:faf977308bdc 84 {
kohlerba 0:faf977308bdc 85 char data[1]; // `data` will store the register data
kohlerba 0:faf977308bdc 86 char data_write[1];
kohlerba 0:faf977308bdc 87 data_write[0] = subAddress;
kohlerba 0:faf977308bdc 88 i2c.write(address, data_write, 1, 1); // no stop
kohlerba 0:faf977308bdc 89 i2c.read(address, data, 1, 0);
kohlerba 0:faf977308bdc 90 return data[0];
kohlerba 0:faf977308bdc 91 }
kohlerba 0:faf977308bdc 92
kohlerba 0:faf977308bdc 93 void readBytes(uint8_t address, uint8_t subAddress, uint8_t count, uint8_t * dest)
kohlerba 0:faf977308bdc 94 {
kohlerba 0:faf977308bdc 95 char data[14];
kohlerba 0:faf977308bdc 96 char data_write[1];
kohlerba 0:faf977308bdc 97 data_write[0] = subAddress;
kohlerba 0:faf977308bdc 98 i2c.write(address, data_write, 1, 1); // no stop
kohlerba 0:faf977308bdc 99 i2c.read(address, data, count, 0);
kohlerba 0:faf977308bdc 100 for(int ii = 0; ii < count; ii++) {
kohlerba 2:d329886938f1 101 dest[ii] = data[ii];
kohlerba 0:faf977308bdc 102 }
kohlerba 0:faf977308bdc 103 }
kohlerba 2:d329886938f1 104 //
kohlerba 2:d329886938f1 105
kohlerba 0:faf977308bdc 106 void setLEDs(pulseWidth pw, ledCurrent red, ledCurrent ir){
kohlerba 0:faf977308bdc 107 uint8_t reg = readByte(MAX30100_ADDRESS, MAX30100_SPO2_CONFIG);
kohlerba 0:faf977308bdc 108 reg = reg & 0xFC; // Set LED_PW to 00
kohlerba 0:faf977308bdc 109 writeByte(MAX30100_ADDRESS, MAX30100_SPO2_CONFIG, reg | pw); // Mask LED_PW
kohlerba 0:faf977308bdc 110 writeByte(MAX30100_ADDRESS, MAX30100_LED_CONFIG, (red<<4) | ir); // write LED configs
kohlerba 0:faf977308bdc 111 }
kohlerba 0:faf977308bdc 112
kohlerba 0:faf977308bdc 113 void setSPO2(sampleRate sr){
kohlerba 0:faf977308bdc 114 uint8_t reg = readByte(MAX30100_ADDRESS, MAX30100_SPO2_CONFIG);
kohlerba 0:faf977308bdc 115 reg = reg & 0xE3; // Set SPO2_SR to 000
kohlerba 0:faf977308bdc 116 writeByte(MAX30100_ADDRESS, MAX30100_SPO2_CONFIG, reg | (sr<<2)); // Mask SPO2_SR
kohlerba 0:faf977308bdc 117 reg = readByte(MAX30100_ADDRESS, MAX30100_MODE_CONFIG);
kohlerba 0:faf977308bdc 118 reg = reg & 0xf8; // Set Mode to 000
kohlerba 0:faf977308bdc 119 writeByte(MAX30100_ADDRESS, MAX30100_SPO2_CONFIG, reg | 0x03); // Mask MODE
kohlerba 0:faf977308bdc 120 }
kohlerba 0:faf977308bdc 121
kohlerba 0:faf977308bdc 122 int getNumSamp(void){
kohlerba 0:faf977308bdc 123 uint8_t wrPtr = readByte(MAX30100_ADDRESS, MAX30100_FIFO_WR_PTR);
kohlerba 0:faf977308bdc 124 uint8_t rdPtr = readByte(MAX30100_ADDRESS, MAX30100_FIFO_RD_PTR);
kohlerba 0:faf977308bdc 125 return (abs( 16 + wrPtr - rdPtr ) % 16);
kohlerba 0:faf977308bdc 126 }
kohlerba 0:faf977308bdc 127
kohlerba 0:faf977308bdc 128 void readSensor(void){
kohlerba 0:faf977308bdc 129 uint8_t temp[4] = {0}; // Temporary buffer for read values
kohlerba 0:faf977308bdc 130 readBytes(MAX30100_ADDRESS, MAX30100_FIFO_DATA, 4, &temp[0]); // Read four times from the FIFO
kohlerba 0:faf977308bdc 131 IR = (temp[0]<<8) | temp[1]; // Combine values to get the actual number
kohlerba 0:faf977308bdc 132 RED = (temp[2]<<8) | temp[3]; // Combine values to get the actual number
kohlerba 0:faf977308bdc 133 }
kohlerba 0:faf977308bdc 134
kohlerba 0:faf977308bdc 135 void shutdown(void){
kohlerba 0:faf977308bdc 136 uint8_t reg = readByte(MAX30100_ADDRESS, MAX30100_MODE_CONFIG); // Get the current register
kohlerba 0:faf977308bdc 137 writeByte(MAX30100_ADDRESS, MAX30100_MODE_CONFIG, reg | 0x80); // mask the SHDN bit
kohlerba 0:faf977308bdc 138 }
kohlerba 0:faf977308bdc 139
kohlerba 0:faf977308bdc 140 void reset(void){
kohlerba 0:faf977308bdc 141 uint8_t reg = readByte(MAX30100_ADDRESS, MAX30100_MODE_CONFIG); // Get the current register
kohlerba 0:faf977308bdc 142 writeByte(MAX30100_ADDRESS, MAX30100_MODE_CONFIG, reg | 0x40); // mask the RESET bit
kohlerba 0:faf977308bdc 143 }
kohlerba 0:faf977308bdc 144
kohlerba 0:faf977308bdc 145 void startup(void){
kohlerba 0:faf977308bdc 146 uint8_t reg = readByte(MAX30100_ADDRESS, MAX30100_MODE_CONFIG); // Get the current register
kohlerba 0:faf977308bdc 147 writeByte(MAX30100_ADDRESS, MAX30100_MODE_CONFIG, reg & 0x7F); // mask the SHDN bit
kohlerba 0:faf977308bdc 148 }
kohlerba 0:faf977308bdc 149
kohlerba 0:faf977308bdc 150 int getRevID(void){
kohlerba 0:faf977308bdc 151 return readByte(MAX30100_ADDRESS, MAX30100_REV_ID);
kohlerba 0:faf977308bdc 152 }
kohlerba 0:faf977308bdc 153
kohlerba 0:faf977308bdc 154 int getPartID(void){
kohlerba 0:faf977308bdc 155 return readByte(MAX30100_ADDRESS, MAX30100_PART_ID);
kohlerba 0:faf977308bdc 156 }
kohlerba 0:faf977308bdc 157
kohlerba 0:faf977308bdc 158 void begin(pulseWidth pw, ledCurrent ir, sampleRate sr){
kohlerba 0:faf977308bdc 159 writeByte(MAX30100_ADDRESS, MAX30100_MODE_CONFIG, 0x02); // Heart rate only
kohlerba 0:faf977308bdc 160 writeByte(MAX30100_ADDRESS, MAX30100_LED_CONFIG, ir);
kohlerba 0:faf977308bdc 161 writeByte(MAX30100_ADDRESS, MAX30100_SPO2_CONFIG, (sr<<2)|pw);
kohlerba 0:faf977308bdc 162 }
kohlerba 1:0c2135629097 163 };
kohlerba 0:faf977308bdc 164 #endif