Intermediate
30 min
0

Keep your oxygen levels in check with MAX30102 and MK64FN1M0VDC12

Better health, better life

Oximeter 5 Click with UNI Clicker

Published May 27, 2023

Click board™

Oximeter 5 Click

Development board

UNI Clicker

Compiler

NECTO Studio

MCU

MK64FN1M0VDC12

Add optical pulse oximetry technology to your solution, enabling accurate and reliable blood oxygen saturation levels monitoring

A

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Hardware Overview

How does it work?

Oximeter 5 Click is based on the MAX30102, a high-sensitivity pulse oximeter and heart-rate sensor from Maxim Integrated, now part of Analog Devices. The MAX30102 integrates Red and IR LEDs, with 660nm red and 880nm IR wavelengths, to modulate LED pulses for oxygen saturation (SpO2) and heart rate measurements. The LED pulse width can be programmed to allow the algorithm to optimize SpO2 and HR accuracy and power consumption based on use cases. The SpO2 subsystem of the MAX30102 contains ambient light cancellation (ALC), a continuous-time oversampling sigma-delta ADC with 18-bit resolution, and a proprietary discrete-time filter. The ALC has an internal Track/Hold circuit to cancel ambient light and increase the effective dynamic

range. The MAX30102 also has an on-chip temperature sensor with an inherent resolution of 0.0625°C for calibrating the temperature dependence of the SpO2 subsystem. The MAX30102 does not require a specific Power-Up sequence but requires a supply voltage of 1.8V to work correctly. Therefore, a small regulating LDO is used, the MAX8511, which provides a 1.8V out of selected 5V or 3.3V mikroBUS™ power rails. Also, it can be shut down through software with zero standby current, allowing the power rails to remain powered at all times. Oximeter 5 Click communicates with MCU using the standard I2C 2-Wire interface with a maximum clock frequency of 400kHz. It is fully adjustable through software registers, and the digital output data is stored in a 32-deep FIFO within the

device. Since the sensor for operation requires a power supply of 1.8V, this Click board™ also features the PCA9306and SN74LVC1T45voltage-level translators. The I2C interface bus lines are routed to the voltage-level translators allowing this Click board™ to work with both 3.3V and 5V MCUs properly. Also, it uses an interrupt pin, the INT pin of the mikroBUS™ socket, to alert the system that the MAX30102 is ready for operation. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC SEL jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development.

Oximeter 5 Click top side image
Oximeter 5 Click lateral side image
Oximeter 5 Click bottom side image

Features overview

Development board

UNI Clicker is a compact development board designed as a complete solution that brings the flexibility of add-on Click boards™ to your favorite microcontroller, making it a perfect starter kit for implementing your ideas. It supports a wide range of microcontrollers, such as different ARM, PIC32, dsPIC, PIC, and AVR from various vendors like Microchip, ST, NXP, and TI (regardless of their number of pins), four mikroBUS™ sockets for Click board™ connectivity, a USB connector, LED indicators, buttons, a debugger/programmer connector, and two 26-pin headers for interfacing with external electronics. Thanks to innovative manufacturing technology, it allows you to build

gadgets with unique functionalities and features quickly. Each part of the UNI Clicker development kit contains the components necessary for the most efficient operation of the same board. In addition to the possibility of choosing the UNI Clicker programming method, using a third-party programmer or CODEGRIP/mikroProg connected to onboard JTAG/SWD header, the UNI Clicker board also includes a clean and regulated power supply module for the development kit. It provides two ways of board-powering; through the USB Type-C (USB-C) connector, where onboard voltage regulators provide the appropriate voltage levels to each component on the board, or using a Li-Po/Li

Ion battery via an onboard battery connector. All communication methods that mikroBUS™ itself supports are on this board (plus USB HOST/DEVICE), including the well-established mikroBUS™ socket, a standardized socket for the MCU card (SiBRAIN standard), and several user-configurable buttons and LED indicators. UNI Clicker is an integral part of the Mikroe ecosystem, allowing you to create a new application in minutes. Natively supported by Mikroe software tools, it covers many aspects of prototyping thanks to a considerable number of different Click boards™ (over a thousand boards), the number of which is growing every day.

UNI clicker double image

Microcontroller Overview

MCU Card / MCU

default

Type

8th Generation

Architecture

ARM Cortex-M4

MCU Memory (KB)

1024

Silicon Vendor

NXP

Pin count

121

RAM (Bytes)

262144

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
NC
NC
RST
NC
NC
CS
NC
NC
SCK
NC
NC
MISO
NC
NC
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
NC
NC
PWM
Interrupt
PC18
INT
NC
NC
TX
NC
NC
RX
I2C Clock
PB2
SCL
I2C Data
PB3
SDA
Power Supply
5V
5V
Ground
GND
GND
1

Take a closer look

Schematic

Oximeter 5 Click Schematic schematic

Step by step

Project assembly

UNI Clicker front image hardware assembly

Start by selecting your development board and Click board™. Begin with the UNI Clicker as your development board.

UNI Clicker front image hardware assembly
Thermo 28 Click front image hardware assembly
SiBRAIN for STM32F745VG front image hardware assembly
Prog-cut hardware assembly
UNI Clicker MB 1 - upright/with-background hardware assembly
Necto image step 2 hardware assembly
Necto image step 3 hardware assembly
Necto image step 4 hardware assembly
Necto image step 5 hardware assembly
Necto image step 6 hardware assembly
Necto image step 7 hardware assembly
Necto No Display image step 8 hardware assembly
Necto image step 9 hardware assembly
Necto image step 10 hardware assembly
Debug Image Necto Step hardware assembly

Track your results in real time

Application Output

After loading the code example, pressing the "DEBUG" button builds and programs it on the selected setup.

Application Output Step 1

After programming is completed, a header with buttons for various actions available in the IDE appears. By clicking the green "PLAY "button, we start reading the results achieved with Click board™.

Application Output Step 3

Upon completion of programming, the Application Output tab is automatically opened, where the achieved result can be read. In case of an inability to perform the Debug function, check if a proper connection between the MCU used by the setup and the CODEGRIP programmer has been established. A detailed explanation of the CODEGRIP-board connection can be found in the CODEGRIP User Manual. Please find it in the RESOURCES section.

Application Output Step 4

Software Support

Library Description

This library contains API for Oximeter 5 Click driver.

Key functions:

  • oximeter5_read_sensor_data Oximeter 5 get sensor data function.

  • oximeter5_get_oxygen_saturation Oximeter 5 get oxygen saturation function.

  • oximeter5_read_temperature Oximeter 5 read temperature function.

Open Source

Code example

This example can be found in NECTO Studio. Feel free to download the code, or you can copy the code below.

/*!
 * @file main.c
 * @brief Oximeter5 Click example
 *
 * # Description
 * This library contains API for Oximeter 5 Click driver.
 * The demo application reads and calculate 
 * SpO2 oxygen saturation data.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initializes I2C driver and log UART.
 * After driver initialization the app set 
 * driver interface setup and  default settings,
 * buffer length of 100 stores 4 seconds of samples running at 25sps
 * read the first 100 samples, and determine the signal range.
 *
 * ## Application Task
 * This is an example that demonstrates the use of the Oximeter 5 Click board™.
 * In this example, display the IR and RED ADC data, 
 * and the SpO2 oxygen saturation data [ 0% - 100% ].
 * Results are being sent to the Usart Terminal where you can track their changes.
 *
 * @note
 * A measurement time of at least 10 seconds is required 
 * for the SpO2 oxygen saturation data to be valid.
 *
 * @author Nenad Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "oximeter5.h"

static oximeter5_t oximeter5;
static log_t logger;
static uint32_t aun_ir_buffer[ 100 ];
static uint32_t aun_red_buffer[ 100 ];
static uint32_t un_min, un_max, un_prev_data, un_brightness;
static float f_temp;
static uint8_t n_spo2;
  
void application_init ( void ) 
{
    log_cfg_t log_cfg;              /**< Logger config object. */
    oximeter5_cfg_t oximeter5_cfg;  /**< Click config object. */

    /** 
     * Logger initialization.
     * Default baud rate: 115200
     * Default log level: LOG_LEVEL_DEBUG
     * @note If USB_UART_RX and USB_UART_TX 
     * are defined as HAL_PIN_NC, you will 
     * need to define them manually for log to work. 
     * See @b LOG_MAP_USB_UART macro definition for detailed explanation.
     */
    LOG_MAP_USB_UART( log_cfg );
    log_init( &logger, &log_cfg );
    log_info( &logger, " Application Init " );

    // Click initialization.
    oximeter5_cfg_setup( &oximeter5_cfg );
    OXIMETER5_MAP_MIKROBUS( oximeter5_cfg, MIKROBUS_1 );
    if ( I2C_MASTER_ERROR == oximeter5_init( &oximeter5, &oximeter5_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }
    Delay_ms( 100 );
    
    if ( OXIMETER5_ERROR == oximeter5_default_cfg ( &oximeter5 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }
    Delay_ms( 100 ); 
    
    un_brightness = 0;
    un_min = 0x3FFFF;
    un_max = 0;
  
    for ( uint8_t n_cnt = 0; n_cnt < 100; n_cnt++ )
    {
        while ( oximeter5_check_interrupt( &oximeter5 ) == OXIMETER5_INTERRUPT_ACTIVE );
        
        oximeter5_read_sensor_data( &oximeter5, &aun_red_buffer[ n_cnt ], &aun_ir_buffer[ n_cnt ] );
    
        if ( un_min > aun_red_buffer[ n_cnt ] )
        {
            un_min = aun_red_buffer[ n_cnt ];
        }
    
        if ( un_max < aun_red_buffer[ n_cnt ] )
        {
            un_max = aun_red_buffer[ n_cnt ];
        }
    }

    oximeter5_get_oxygen_saturation( &aun_ir_buffer[ 0 ], 100, &aun_red_buffer[ 0 ], &n_spo2 );
    log_info( &logger, " Application Task " );
    Delay_ms( 100 ); 
}

void application_task ( void ) 
{
    for ( uint8_t n_cnt = 25; n_cnt < 100; n_cnt++ )
    {
        aun_red_buffer[ n_cnt - 25 ] = aun_red_buffer[ n_cnt ];
        aun_ir_buffer[ n_cnt - 25 ] = aun_ir_buffer[ n_cnt ];

        if ( un_min > aun_red_buffer[ n_cnt ] )
        {
            un_min = aun_red_buffer[ n_cnt ];
        }
      
        if ( un_max < aun_red_buffer[ n_cnt ] )
        {
            un_max=aun_red_buffer[n_cnt];
        }
    }

    for ( uint8_t n_cnt = 75; n_cnt < 100; n_cnt++ )
    {
        un_prev_data = aun_red_buffer[ n_cnt - 1 ];
        while ( oximeter5_check_interrupt( &oximeter5 ) == OXIMETER5_INTERRUPT_ACTIVE ); 

        oximeter5_read_sensor_data( &oximeter5, &aun_red_buffer[ n_cnt ], &aun_ir_buffer[ n_cnt ] );

        if ( aun_red_buffer[ n_cnt ] > un_prev_data )
        {
            f_temp = aun_red_buffer[ n_cnt ]-un_prev_data;
            f_temp /= ( un_max - un_min );
            f_temp *= MAX_BRIGHTNESS;
            f_temp = un_brightness - f_temp;
        
            if ( f_temp < 0 )
            {
                un_brightness = 0;
            }
            else
            {
                un_brightness = ( uint32_t ) f_temp;
            }
        }
        else
        {
            f_temp = un_prev_data - aun_red_buffer[ n_cnt ];
            f_temp /= ( un_max - un_min );
            f_temp *= MAX_BRIGHTNESS;
            un_brightness += ( uint32_t ) f_temp;
            
            if ( un_brightness > MAX_BRIGHTNESS )
            {
                un_brightness = MAX_BRIGHTNESS;
            }
        }
      
        if ( ( OXIMETER5_OK == oximeter5_get_oxygen_saturation( &aun_ir_buffer[ 0 ], 100, &aun_red_buffer[ 0 ], &n_spo2 ) ) )
        {
            if ( aun_ir_buffer[n_cnt] > 10000  ) 
            {
                log_printf( &logger, "\tIR    : %lu \r\n", aun_ir_buffer[ n_cnt ] );
                log_printf( &logger, "\tRED   : %lu \r\n", aun_red_buffer[ n_cnt ] ); 
                log_printf( &logger, "- - - - - - - - - - - - - - -\r\n" );
                log_printf( &logger, "\tSPO2  : %d %%\r\n", ( uint16_t ) n_spo2 );
                log_printf( &logger, "-----------------------------\r\n" );
                Delay_ms( 100 );       
            }
            else
            {
                Delay_ms( 10 );      
            }
        }
    }
}

void main ( void ) 
{
    application_init( );

    for ( ; ; ) 
    {
        application_task( );
    }
}

// ------------------------------------------------------------------------ END

Additional Support

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