Sample host software for the Maxim Integrated MAX31875 Low Power Small Package Temperature Sensor. Hosted on the MAX32630FTHR. The MAX31875 may be used in wearables, thermostats, thermometers, and hardware temperature supervisors.

Dependencies:   MAX31875_Temperature_Sensor_Low_Power max32630fthr USBDevice

main.cpp

Committer:
phonemacro
Date:
17 months ago
Revision:
0:77036686489d

File content as of revision 0:77036686489d:

/*******************************************************************************
* Copyright (C) 2019 Maxim Integrated Products, Inc., All Rights Reserved.
*
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*
* The above copyright notice and this permission notice shall be included
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* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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* IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
* OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* Except as contained in this notice, the name of Maxim Integrated
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* Products, Inc. Branding Policy.
*
* The mere transfer of this software does not imply any licenses
* of trade secrets, proprietary technology, copyrights, patents,
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* property whatsoever. Maxim Integrated Products, Inc. retains all
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*******************************************************************************
*/
#include "mbed.h"
#include "max32630fthr.h"
#include "max31875.h"
#include "USBSerial.h"
 
MAX32630FTHR pegasus(MAX32630FTHR::VIO_1V8); 
 
DigitalOut rLED(LED1);
DigitalOut gLED(LED2);
DigitalOut bLED(LED3);
 
I2C i2cBus(P3_4, P3_5);

// main() runs in its own thread in the OS
// (note the calls to Thread::wait below for delays)
/**
* @brief Sample main program for MAX31875
* @version 1.0000.0000
*
* @details Sample main program for MAX31875
* The prints are sent to the terminal window (9600, 8n1).
* The program sets the GPIOs to 1.8V and the program
* configures the chip and reads temperatures.
* To run the program, drag and drop the .bin file into the 
* DAPLINK folder. After it finishes flashing, cycle the power or 
* reset the Pegasus (MAX32630FTHR) after flashing by pressing the button on
* the Pegasus next to the battery connector or the button
* on the MAXREFDES100HDK.
*/
int main()
{
    uint32_t i;
    float temperature;
    uint16_t cfg;
    DigitalOut rLED(LED1, LED_OFF);
    DigitalOut gLED(LED2, LED_OFF);
    DigitalOut bLED(LED3, LED_OFF);
    gLED = LED_ON;
    printf("MAX31875 Small Package Temperature Sensor example source code.\r\n");
    printf("\r\n");

    MAX31875 temp_sensor(i2cBus, MAX31875_I2C_SLAVE_ADR_R0);
    i2cBus.frequency(1000000);
   
    /* Configure for fault filter 1, comparator, continuous,
     * normal format, 8 sps, 12 bit resolution
     */
    temp_sensor.write_cfg(uint16_t(MAX31875_CFG_FAULT_FILTER_1 | 
        MAX31875_CFG_COMPARATOR_MODE | MAX31875_CFG_CONTINUOUS | 
        MAX31875_CFG_NORMAL_FORMAT | MAX31875_CFG_CONV_RATE_8 | 
        MAX31875_CFG_RESOLUTION_12BIT));
    for (i = 0; i < 10; i++) {
        wait(MAX31875_WAIT_CONV_RATE_8);
        temperature = temp_sensor.read_reg_as_temperature(MAX31875_REG_TEMPERATURE);
        printf("Temperature = %3.4f Celsius, %3.4f Fahrenheit\r\n", 
            temperature, temp_sensor.celsius_to_fahrenheit(temperature));
    }
    temp_sensor.read_reg(&cfg, MAX31875_REG_CONFIGURATION);
    printf("Configuration Register = 0x%04Xh \r\n", cfg);

    printf("\r\n");


    /* Configure for fault filter 4, interrupt, shutdown,
     * extended format, 0.25 sps, 10 bit resolution, start one-shot
     */
    for (i = 0; i < 5; i++) {
        temp_sensor.write_cfg(uint16_t(MAX31875_CFG_FAULT_FILTER_4 | 
            MAX31875_CFG_INTERRUPT_MODE | MAX31875_CFG_SHUTDOWN |
            MAX31875_CFG_EXTENDED_FORMAT| MAX31875_CFG_CONV_RATE_0_25 | 
            MAX31875_CFG_RESOLUTION_10BIT | MAX31875_CFG_ONE_SHOT_START));
        wait(MAX31875_WAIT_CONV_RATE_0_25);
        temperature = temp_sensor.read_reg_as_temperature(MAX31875_REG_TEMPERATURE);
        printf("Temperature = %3.4f Celsius, %3.4f Fahrenheit\r\n", 
            temperature, temp_sensor.celsius_to_fahrenheit(temperature));
    }
    temp_sensor.read_reg(&cfg, MAX31875_REG_CONFIGURATION);
    printf("Configuration Register = 0x%04Xh \r\n", cfg);

    printf("\r\n\r\n");
#if 0
    temp_sensor.write_trip_low(3.0625f);
    temp_sensor.read_reg(&cfg, MAX31875_REG_CONFIGURATION);
    temperature = temp_sensor.read_reg_as_temperature(MAX31875_REG_THYST);
    printf("Thyst Temperature = %3.4f Celsius, %3.4f Fahrenheit\r\n", 
            temperature, temp_sensor.celsius_to_fahrenheit(temperature));

    temp_sensor.write_trip_high(129.0625f);
    temperature = temp_sensor.read_reg_as_temperature(MAX31875_REG_TOS);
    printf("TOS Temperature = %3.4f Celsius, %3.4f Fahrenheit\r\n", 
            temperature, temp_sensor.celsius_to_fahrenheit(temperature));
    printf("\r\n\r\n");
#endif
    while (true) {  // Blink the green LED 
        gLED = !gLED;
        wait(0.5);
    }
}