Revision 0:4a3d6ac5042d, committed 2019-01-26

Comitter:

phonemacro

Date:

Sat Jan 26 23:55:38 2019 +0000

Child:

1:bb6f11be119f

Commit message:

Initial commit for one-shot temperature readings.

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/max31723.cpp	Sat Jan 26 23:55:38 2019 +0000
@@ -0,0 +1,97 @@
+/*******************************************************************************
+* Copyright (C) 2019 Maxim Integrated Products, Inc., All Rights Reserved.
+*
+* Permission is hereby granted, free of charge, to any person obtaining a
+* copy of this software and associated documentation files (the "Software"),
+* to deal in the Software without restriction, including without limitation
+* the rights to use, copy, modify, merge, publish, distribute, sublicense,
+* and/or sell copies of the Software, and to permit persons to whom the
+* Software is furnished to do so, subject to the following conditions:
+*
+* The above copyright notice and this permission notice shall be included
+* in all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+* 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
+* Products, Inc. shall not be used except as stated in the Maxim Integrated
+* Products, Inc. Branding Policy.
+*
+* The mere transfer of this software does not imply any licenses
+* of trade secrets, proprietary technology, copyrights, patents,
+* trademarks, maskwork rights, or any other form of intellectual
+* property whatsoever. Maxim Integrated Products, Inc. retains all
+* ownership rights.
+*******************************************************************************
+*/
+#include "max31723.h"
+ 
+MAX31723::MAX31723(SPI &spi, DigitalOut &ce_pin) : m_spi(spi), m_chip_enable(ce_pin)
+{
+    m_chip_enable = 0;
+}
+ 
+int MAX31723::write_reg(uint8_t val, uint8_t reg)
+{
+    
+    m_chip_enable = 1;
+    m_spi.write(reg);
+    m_spi.write(val);
+    m_chip_enable = 0;
+    return MAX31723_NO_ERROR;
+}
+ 
+int MAX31723::read_reg(uint8_t &val, uint8_t reg)
+{
+    
+    m_chip_enable = 1;
+    m_spi.write(reg);
+    val = m_spi.write(0);
+    m_chip_enable = 0;
+    return MAX31723_NO_ERROR;
+}
+
+int MAX31723::perform_one_shot(uint8_t resolution)
+{
+    if (resolution <= MAX31723_CFG_RESOLUTION_12BIT)
+        write_reg(resolution | MAX31723_CFG_1SHOT | MAX31723_CFG_STANDBY,
+            MAX31723_REG_CFG | MAX31723_WRITE_MASK);
+    else
+        return MAX31723_ERROR;
+    return MAX31723_NO_ERROR;
+}
+
+float MAX31723::read_temp()
+{
+    uint8_t lsb, msb;
+    uint16_t raw_temp;
+    float temperature;
+    
+    read_reg(lsb, MAX31723_REG_TEMP_LSB);
+    read_reg(msb, MAX31723_REG_TEMP_MSB);
+
+    raw_temp =  int16_t((msb << 8) | (lsb));
+    raw_temp =  raw_temp >> 4;
+    temperature = raw_temp * 0.0625 ;
+    return temperature;
+}
+
+
+float MAX31723::celsius_to_fahrenheit(float temp_c)
+{
+    float temp_f;
+    temp_f = ((temp_c * 9)/5) + 32;
+    return temp_f;
+}
+
+MAX31723::~MAX31723(void) 
+{
+  //empty block
+}
+ 

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/max31723.h	Sat Jan 26 23:55:38 2019 +0000
@@ -0,0 +1,163 @@
+/*******************************************************************************
+* Copyright (C) 2018 Maxim Integrated Products, Inc., All Rights Reserved.
+*
+* Permission is hereby granted, free of charge, to any person obtaining a
+* copy of this software and associated documentation files (the "Software"),
+* to deal in the Software without restriction, including without limitation
+* the rights to use, copy, modify, merge, publish, distribute, sublicense,
+* and/or sell copies of the Software, and to permit persons to whom the
+* Software is furnished to do so, subject to the following conditions:
+*
+* The above copyright notice and this permission notice shall be included
+* in all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+* 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
+* Products, Inc. shall not be used except as stated in the Maxim Integrated
+* Products, Inc. Branding Policy.
+*
+* The mere transfer of this software does not imply any licenses
+* of trade secrets, proprietary technology, copyrights, patents,
+* trademarks, maskwork rights, or any other form of intellectual
+* property whatsoever. Maxim Integrated Products, Inc. retains all
+* ownership rights.
+*******************************************************************************
+* @file MAX31723.h
+*******************************************************************************
+*/
+#ifndef MAX31723_H
+#define MAX31723_H
+
+#include "mbed.h"
+
+#define MAX31723_NO_ERROR   0
+#define MAX31723_ERROR      -1
+
+#define MAX31723_WRITE_MASK             0x80
+
+#define MAX31723_REG_CFG                0x00
+#define MAX31723_REG_TEMP_LSB           0x01
+#define MAX31723_REG_TEMP_MSB           0x02
+
+/* Configuration, Status masks */
+#define MAX31723_CFG_CONTINUOUS         0x00
+#define MAX31723_CFG_STANDBY            0x01
+
+#define MAX31723_CFG_RESOLUTION_9BIT    0x00
+#define MAX31723_CFG_RESOLUTION_10BIT   0x02
+#define MAX31723_CFG_RESOLUTION_11BIT   0x04
+#define MAX31723_CFG_RESOLUTION_12BIT   0x06
+
+#define MAX31723_CFG_TM_MODE_INTERRUPT  0x08
+#define MAX31723_CFG_1SHOT              0x10
+#define MAX31723_CFG_NVB_NVRAM_BUSY     0x20
+#define MAX31723_CFG_MEMW_CFG_WR_EEPROM 0x40
+
+#define MAX31723_CONV_TIME_MSEC_9BIT    .025
+#define MAX31723_CONV_TIME_MSEC_10BIT   .050
+#define MAX31723_CONV_TIME_MSEC_11BIT   .100
+#define MAX31723_CONV_TIME_MSEC_12BIT   .200
+
+/**
+* @brief 9-bit to 12bit device temperature sensor with digital-to-analog converters (DACs)
+*        for the MAX31723, MAX5214.
+* @version 1.0000.0000
+*
+* @details The MAX31722/MAX31723 provides device temperature readings
+* for thermostats and thermometers. Communications may be either SPI or
+* 3-wire. There are two operating modes available: comparator or interrupt.
+* Temperature limits may be stored in NVRAM so that the TOUT_N pin can be 
+* triggered when the limits are exceeded while in the comparator mode.
+* Typically applications are for temperature sensitive systems.
+*
+*/
+
+class MAX31723{
+    public:
+    
+    /**************************************************************
+    * @brief Constructor for MAX31723 Class.  
+    * 
+    * @details Requires an existing SPI object as well as a DigitalOut object. 
+    * The DigitalOut object is used for a chip enable signal
+    *
+    * On Entry:
+    *     @param[in] spi - pointer to existing SPI object
+    *     @param[in] ce_pin - pointer to a DigitalOut pin object
+    *     @param[in] ic_variant - which type of MAX521x is used
+    *
+    * On Exit:
+    *
+    * @return None
+    ***************************************************************
+    */
+    MAX31723(SPI &spi, DigitalOut &ce_pin); 
+
+    /** 
+     * @brief Write a value to a register
+     * @param val - 8-bit value to write to the register
+     * @param reg - register address
+     * @return 0 on success, negative number on failure
+     */
+    int write_reg(uint8_t val, uint8_t reg);
+
+    /** 
+     * @brief Read a value from a register
+     * @param val - 8-bit value read from the register
+     * @param reg - register address
+     * @return 0 on success, negative number on failure
+     */
+    int read_reg(uint8_t &val, uint8_t reg);
+
+    /** 
+     * @brief Write a value to a register
+     * @param val - 8-bit value to write to the register
+     * @param reg - register address
+     * @return temprature in degrees celsius
+     */
+    float read_temp();
+
+    /** 
+     * @brief Configures the device to perform a one-shot temperature reading
+     *        and places the device in standby mode.
+     * @param resolution - the resolution of the calculation is set to this
+     * @return 0 on success, negative number on failure
+     */
+    int perform_one_shot(uint8_t resolution);
+
+    /** 
+     * @brief Converts Celcius degrees to Fahrenheit
+     * @param temp_c - the temperature in Celsius degrees
+     * @return 0 on success, negative number on failure
+     */
+    float celsius_to_fahrenheit(float temp_c);
+
+
+    /************************************************************
+     * @brief Default destructor for MAX31723 Class.  
+     *
+     * @details Destroys SPI object if owner 
+     *
+     * On Entry:
+     *
+     * On Exit:
+     *
+     * @return None
+     *************************************************************
+     */
+    ~MAX31723();
+    private:
+    // SPI object
+    SPI &m_spi;
+    // chip enable pin
+    DigitalOut &m_chip_enable;
+};
+
+#endif
\ No newline at end of file