rt-thread/bsp/nuvoton/libraries/nu_packages/MAX31875/libraries/max31875_c.c

/*******************************************************************************
* 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 "max31875.h"
#include "max31875_c.h"

/******************************************************************************/
/*  C version for MAX31875 driver                                             */
/******************************************************************************/

/* @var max31875_write_address, max31875_read_address
 * @brief I2C address
 */
static uint32_t max31875_extended_format;

int max31875_init(uint8_t slave_address)
{
    max31875_extended_format = 0;
    return MAX31875_NO_ERROR;
}


/******************************************************************************/
int max31875_read_reg(uint16_t *value, char reg, S_MAX31875 *psObj)
{
    int32_t ret;
    char data[2] = {0, 0};
    max31875_raw_data tmp;

    if (reg <= MAX31875_REG_MAX)
    {
        /* write to the Register Select */
        ret = psObj->read(psObj->address, &reg, 1, data, 2);
        /* read the two bytes of data */
        if (ret == 0)
        {
            tmp.s_lm.msb = data[0];
            tmp.s_lm.lsb = data[1];
            *value = tmp.uwrd;
            return MAX31875_NO_ERROR;
        }
        else
        {
            //printf("%s: failed to write to Register Select: ret: %d\r\n", __func__, ret);
        }
    }
    else
    {
        //printf("%s: register address is not correct: register: %d\r\n",  __func__, reg);
    }
    return MAX31875_ERROR;
}

float max31875_read_reg_as_temperature(uint8_t reg, S_MAX31875 *psObj)
{
    max31875_raw_data tmp;
    float temperature;
    if (reg == MAX31875_REG_TEMPERATURE ||
            reg == MAX31875_REG_THYST_LOW_TRIP || reg == MAX31875_REG_TOS_HIGH_TRIP)
    {
        max31875_read_reg(&tmp.uwrd, reg, psObj);
        temperature = (float)tmp.s_ms.magnitude_bits;
        if (max31875_extended_format)
            temperature *= MAX31875_CF_EXTENDED_FORMAT;
        else
            temperature *= MAX31875_CF_NORMAL_FORMAT;
        if (tmp.s_ms.sign_bit)
            temperature = -temperature;
        return temperature;
    }
    else
    {
        //printf("%s: register is invalid, %d r\n", __func__, reg);
        return 0;
    }
}


/******************************************************************************/
int max31875_write_reg(uint16_t value, char reg, S_MAX31875 *psObj)
{
    int32_t ret;
    char cmd[3];
    max31875_raw_data tmp;

    if (reg >= MAX31875_REG_CONFIGURATION && reg <= MAX31875_REG_MAX)
    {
        cmd[0] = reg;
        tmp.uwrd = value;
        cmd[1] = tmp.s_lm.msb;
        cmd[2] = tmp.s_lm.lsb;
        ret = psObj->write(psObj->address, cmd, 3);
        if (ret == 0)
        {
            if (MAX31875_REG_CONFIGURATION == reg)
            {
                max31875_extended_format = 0;
                if (tmp.uwrd & MAX31875_CFG_EXTENDED_FORMAT)
                    max31875_extended_format = 1;
            }
            return MAX31875_NO_ERROR;
        }
        else
        {
            //printf("%s: I2C write error %d\r\n", __func__, ret);
            return MAX31875_ERROR;
        }
    }
    else
    {
        //printf("%s: register value invalid %x\r\n", __func__, reg);
        return MAX31875_ERROR;
    }
}


int max31875_write_cfg(uint16_t cfg, S_MAX31875 *psObj)
{
    return max31875_write_reg(cfg, MAX31875_REG_CONFIGURATION, psObj);
}


int max31875_write_trip_low(float temperature, S_MAX31875 *psObj)
{
    max31875_raw_data raw;
    raw.uwrd = 0;
    if (temperature < 0)
    {
        raw.s_ms.sign_bit = 1;
        temperature = -temperature;
    }
    if (max31875_extended_format)
        temperature /= MAX31875_CF_EXTENDED_FORMAT;
    else
        temperature /= MAX31875_CF_NORMAL_FORMAT;
    raw.s_ms.magnitude_bits = (uint16_t)temperature;
    return max31875_write_reg(raw.uwrd, MAX31875_REG_THYST_LOW_TRIP, psObj);
}


int max31875_write_trip_high(float temperature, S_MAX31875 *psObj)
{
    max31875_raw_data raw;
    raw.uwrd = 0;
    if (temperature < 0)
    {
        raw.s_ms.sign_bit = 1;
        temperature = -temperature;
    }
    if (max31875_extended_format)
        temperature /= MAX31875_CF_EXTENDED_FORMAT;
    else
        temperature /= MAX31875_CF_NORMAL_FORMAT;
    raw.s_ms.magnitude_bits = (uint16_t)temperature;
    return max31875_write_reg(raw.uwrd, MAX31875_REG_TOS_HIGH_TRIP, psObj);
}


float max31875_celsius_to_fahrenheit(float temp_c)
{
    float temp_f;
    temp_f = ((temp_c * 9) / 5) + 32;
    return temp_f;
}