Seeed_MCP9808.cpp

/*
    Seeed_MCP9808.cpp
    Driver for DIGITAL I2C HUMIDITY AND TEMPERATURE SENSOR

    Copyright (c) 2018 Seeed Technology Co., Ltd.
    Website    : www.seeed.cc
    Author     : downey
    Create Time: May 2018
    Change Log :

    The MIT License (MIT)

    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 THE
    AUTHORS OR COPYRIGHT HOLDERS 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.
*/


#include "Seeed_MCP9808.h"


/** @brief Set configuration of sensor.
    @param Register addr of sensor configuration.
    @param The value to set.
    @return 0 if success;

 * */
s32 MCP9808::set_config(u8 addr, u16 cfg) {
    return IIC_write_16bit(addr, cfg);
}

/** @brief Set upper limit of sensor.
    @param Register addr of upper limit.
    @param The value to set.
    @return 0 if success;
 * */
s32 MCP9808::set_upper_limit(u8 addr, u16 cfg) {
    return IIC_write_16bit(addr, cfg);
}

/** @brief Set lower limit of sensor.
    @param Register addr of lower limit.
    @param The value to set.
    @return 0 if success;
 * */
s32 MCP9808::set_lower_limit(u8 addr, u16 cfg) {
    return IIC_write_16bit(addr, cfg);
}

/** @brief Set critical limit of sensor.
    @param Register addr of critical limit.
    @param The value to set.
    @return 0 if success;
 * */
s32 MCP9808::set_critical_limit(u8 addr, u16 cfg) {
    return IIC_write_16bit(addr, cfg);
}

/** @brief Set resolution of sensor.range:0,0.25,0.125,0.0625
    @param Register addr of resolution.
    @param The value to set.
    @return 0 if success;
 * */
s32 MCP9808::set_resolution(u8 addr, u8 resolution) {
    return IIC_write_byte(addr, resolution);
}


/** @brief caculate u16 data to a float temp num;
    @param register addr of ambient temp.
    @param dst temp data.
 * */
s32 MCP9808::read_temp_reg(u8 addr, u16* temp) {
    IIC_read_16bit(addr, temp);
    return 0;
}


/** @brief caculate u16 data to a float temp num;
    @param u16-form data.
    @return float-form temp data.
 * */
float MCP9808::caculate_temp(u16 temp_value) {
    float temp = 0;
    u8 temp_upper = 0, temp_lower = 0;
    temp_upper = (u8)(temp_value >> 8);
    temp_lower = (u8)temp_value;
    if (temp_upper & SIGN_BIT) {
        temp_upper &= 0x0f;
        temp = 256 - (temp_upper * 16 + temp_lower * 0.0625);
        temp *= -1;
    }
    temp_upper &= 0x0f;
    temp = temp_upper * 16 + temp_lower * 0.0625;
    return temp;
}


/** @brief Get the temperature data from sensor,caculate,output a float num;
    @param dst data.

 * */
void MCP9808::get_temp(float* temp) {
    u16 temp_value = 0;
    read_temp_reg(AMBIENT_TEMPERATURE_ADDR, &temp_value);
    *temp = caculate_temp(temp_value);
}





/** @brief Init IIC ,set resolution of sensor.default is 0.0625
    @return 0 if success.

 * */
s32 MCP9808::init() {
    IIC_begin();

    //High accuracy cost more time,if you want to reducing time of running,try to change this setting.
    if (set_resolution(SET_RESOLUTION_ADDR, RESOLUTION_0_0625_DEGREE)) {
        return -1;
    }
    return 0;
}

MCP9808::MCP9808(u8 IIC_ADDR) {
    set_iic_addr(IIC_ADDR);
}


/**********************************************************************************************************/
/************************************************IIC PART************************************************/
/**********************************************************************************************************/



s32 MCP_IIC_OPRTS::IIC_write_byte(u8 reg, u8 byte) {
    Wire.beginTransmission(_IIC_ADDR);
    Wire.write(reg);
    Wire.write(byte);
    return Wire.endTransmission();
}


s32 MCP_IIC_OPRTS::IIC_write_16bit(u8 reg, u16 value) {
    Wire.beginTransmission(_IIC_ADDR);
    Wire.write(reg);

    Wire.write((u8)(value >> 8));
    Wire.write((u8)value);
    return Wire.endTransmission();
}




void MCP_IIC_OPRTS::IIC_read_byte(u8 reg, u8* byte) {
    Wire.beginTransmission(_IIC_ADDR);
    Wire.write(reg);
    Wire.endTransmission(false);

    Wire.requestFrom(_IIC_ADDR, (u8)1);
    while (1 != Wire.available());
    *byte = Wire.read();

}

void MCP_IIC_OPRTS::IIC_read_16bit(u8 start_reg, u16* value) {
    u8 val = 0;
    *value = 0;
    Wire.beginTransmission(_IIC_ADDR);
    Wire.write(start_reg);
    Wire.endTransmission(false);

    Wire.requestFrom(_IIC_ADDR, sizeof(u16));
    while (sizeof(u16) != Wire.available());
    val = Wire.read();
    *value |= (u16)val << 8;
    val = Wire.read();
    *value |= val;
}



void MCP_IIC_OPRTS::set_iic_addr(u8 IIC_ADDR) {
    _IIC_ADDR = IIC_ADDR;
}