ATY_LIB/SHT3X_ATY.c

/**
* @file SHT3X_ATY.c
*
* @param Project DEVICE_GENERAL_ATY_LIB
*
* @author ATY
*
* @copyright
*       - Copyright 2017 - 2023 MZ-ATY
*       - This code follows:
*           - MZ-ATY Various Contents Joint Statement -
*               <a href="https://mengze.top/MZ-ATY_VCJS">
*                        https://mengze.top/MZ-ATY_VCJS</a>
*           - CC 4.0 BY-NC-SA -
*               <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/">
*                        https://creativecommons.org/licenses/by-nc-sa/4.0/</a>
*       - Your use will be deemed to have accepted the terms of this statement.

*
* @brief Familiar functions of SHT3X tem&hum transistor for all devices
*
* @version
*       - 1_01_200318 > ATY
*           -# Preliminary version, first Release
********************************************************************************
*/

#ifndef __SHT3X_ATY_C
#define __SHT3X_ATY_C

#include "SHT3X_ATY.h"

/******************************* For user *************************************/

/******************************************************************************/

float temperatureSHT3X = 0.0;
float humiditySHT3X = 0.0;
/*  0: 0-65T, 10-90H, Best accuracy
    1: -40-0/65-120T, 0-10/90-100H, not good accuracy, warning
    2: out of limit data, error
*/
uint8_t warningFlag = 0;


/**
 * @brief   calc crc with SHT3X data
 * @param   sht3xData data to calc
 * @param   nbrOfBytes length of data to calc
 * @return  uint8_t crc value
 */
uint8_t SHT3X_CalcCrc(uint8_t* sht3xData, uint8_t nbrOfBytes)
{
    uint8_t bit_t;          // bit mask
    uint8_t crc = 0xFF;     // calculated checksum
    uint8_t byteCtr;        // byte counter

    // calculates 8-Bit checksum with given polynomial
    for(byteCtr = 0; byteCtr < nbrOfBytes; byteCtr++)
    {
        crc ^= sht3xData[byteCtr];
        for(bit_t = 8; bit_t > 0; --bit_t)
        {
            if(crc & 0x80)
                crc = (crc << 1) ^ POLYNOMIAL;
            else
                crc = (crc << 1);
        }
    }
    return crc;
}

/**
 * @brief   check crc with SHT3X data
 * @param   sht3xData data to check
 * @param   nbrOfBytes length of data to check
 * @param   checksum compare value with calculated crc
 * @return  !0: wrong, 0: success
 */
uint8_t SHT3X_CheckCrc(uint8_t* sht3xData, uint8_t nbrOfBytes, uint8_t checksum)
{
    // calculates 8-Bit checksum
    uint8_t crc = SHT3X_CalcCrc(sht3xData, nbrOfBytes);

    if(crc != checksum)
        return 1;
    else
        return 0;
}

/**
 * @brief   write command to SHT3X
 * @param   cmd command to send
 */
void SHT3X_WriteCommand(sht3xCommands cmd)
{
    uint8_t cmd_t[2];
    cmd_t[0] = cmd >> 8;
    cmd_t[1] = cmd & 0xFF;
    I2C_Write(SHT3X_ADDR, cmd_t, 2);
}

/**
 * @brief   start periodic measurment
 * @param   repeatability repeatability
 * @param   frequency frequency
 * @note    use depending on the required repeatability and frequency,
 *          the corresponding command
 */
void SHT3X_StartPeriodicMeasurment(sht3xRepeatability repeatability, sht3xFrequency frequency)
{
    switch(repeatability)
    {
        case REPEATAB_LOW: // low repeatability
            switch(frequency)
            {
                case FREQUENCY_HZ5:  // low repeatability,  0.5 Hz
                    SHT3X_WriteCommand(CMD_MEAS_PERI_05_L);
                    break;
                case FREQUENCY_1HZ:  // low repeatability,  1.0 Hz
                    SHT3X_WriteCommand(CMD_MEAS_PERI_1_L);
                    break;
                case FREQUENCY_2HZ:  // low repeatability,  2.0 Hz
                    SHT3X_WriteCommand(CMD_MEAS_PERI_2_L);
                    break;
                case FREQUENCY_4HZ:  // low repeatability,  4.0 Hz
                    SHT3X_WriteCommand(CMD_MEAS_PERI_4_L);
                    break;
                case FREQUENCY_10HZ: // low repeatability, 10.0 Hz
                    SHT3X_WriteCommand(CMD_MEAS_PERI_10_L);
                    break;
                default:
                    break;
            }
            break;

        case REPEATAB_MEDIUM: // medium repeatability
            switch(frequency)
            {
                case FREQUENCY_HZ5:  // medium repeatability,  0.5 Hz
                    SHT3X_WriteCommand(CMD_MEAS_PERI_05_M);
                    break;
                case FREQUENCY_1HZ:  // medium repeatability,  1.0 Hz
                    SHT3X_WriteCommand(CMD_MEAS_PERI_1_M);
                    break;
                case FREQUENCY_2HZ:  // medium repeatability,  2.0 Hz
                    SHT3X_WriteCommand(CMD_MEAS_PERI_2_M);
                    break;
                case FREQUENCY_4HZ:  // medium repeatability,  4.0 Hz
                    SHT3X_WriteCommand(CMD_MEAS_PERI_4_M);
                    break;
                case FREQUENCY_10HZ: // medium repeatability, 10.0 Hz
                    SHT3X_WriteCommand(CMD_MEAS_PERI_10_M);
                    break;
                default:
                    break;
            }
            break;

        case REPEATAB_HIGH: // high repeatability
            switch(frequency)
            {
                case FREQUENCY_HZ5:  // high repeatability,  0.5 Hz
                    SHT3X_WriteCommand(CMD_MEAS_PERI_05_H);
                    break;
                case FREQUENCY_1HZ:  // high repeatability,  1.0 Hz
                    SHT3X_WriteCommand(CMD_MEAS_PERI_1_H);
                    break;
                case FREQUENCY_2HZ:  // high repeatability,  2.0 Hz
                    SHT3X_WriteCommand(CMD_MEAS_PERI_2_H);
                    break;
                case FREQUENCY_4HZ:  // high repeatability,  4.0 Hz
                    SHT3X_WriteCommand(CMD_MEAS_PERI_4_H);
                    break;
                case FREQUENCY_10HZ: // high repeatability, 10.0 Hz
                    SHT3X_WriteCommand(CMD_MEAS_PERI_10_H);
                    break;
                default:
                    break;
            }
            break;
        default:
            break;
    }
}

/**
 * @brief   calc real value from 16 bit data
 * @param   temperature temperature 16 bit origin value
 * @param   humidity humidity 16 bit origin value
 */
void SHT3X_ValuePorcess(uint16_t* temperature, uint16_t* humidity)
{
    temperatureSHT3X = -45 + 175 * (1.0 * (*temperature) / 65535);
    humiditySHT3X = 100 * (1.0 * (*humidity) / 65535);
    warningFlag = 0;
    if(temperatureSHT3X < 0 || temperatureSHT3X>65)
        warningFlag = 1;
    else if(temperatureSHT3X < -40)
    {
        warningFlag = 2;
        temperatureSHT3X = -40;
    }
    else if(temperatureSHT3X > 120)
    {
        warningFlag = 2;
        temperatureSHT3X = 120;
    }
    if(humiditySHT3X < 10 || humiditySHT3X>90)
        warningFlag = 1;
    else if(humiditySHT3X < 0)
    {
        warningFlag = 2;
        humiditySHT3X = 0;
    }
    else if(humiditySHT3X > 100)
    {
        warningFlag = 2;
        humiditySHT3X = 100;
    }
}

/**
 * @brief   read all data from SHT3X
 * @param   temperature temperature 16 bit origin value
 * @param   humidity humidity 16 bit origin value
 */
void SHT3X_ReadDataAndCrc(uint16_t* temperature, uint16_t* humidity)
{
    uint8_t bytes[6]; // read 2 data array and 1 checksum byte

    // read two data bytes and one checksum byte
    I2C_Read(SHT3X_ADDR, bytes, 6);

    // verify checksum then combine the two bytes to a 16-bit value
    if(!SHT3X_CheckCrc(bytes, 2, bytes[2]))
        *temperature = (bytes[0] << 8) | bytes[1];
    // else
    //     *temperature = 0;
    if(!SHT3X_CheckCrc(bytes + 3, 2, bytes[5]))
        *humidity = (bytes[3] << 8) | bytes[4];
    // else
    //     *humidity = 0;
    SHT3X_ValuePorcess(temperature, humidity);
}


/**
 * @brief   read data and calc real value
 */
void SHT3X_ReadMeasurementBuffer(void)
{
    uint16_t hexValueTemp = 0;
    uint16_t hexValueHumi = 0;

    SHT3X_WriteCommand(CMD_FETCH_DATA);
    SHT3X_ReadDataAndCrc(&hexValueTemp, &hexValueHumi);
}

/**
 * @brief   start measurement in clock stretching mode
 * @param   repeatability repeatability
 * @note    use depending on the required repeatability, the corresponding command
 */
void SHT3X_GetTempAndHumiClkStretch(sht3xRepeatability repeatability)
{
    uint16_t hexTempValue = 0;
    uint16_t hexHumiValue = 0;

    switch(repeatability)
    {
        case REPEATAB_LOW:
            SHT3X_WriteCommand(CMD_MEAS_CLOCKSTR_L);
            break;
        case REPEATAB_MEDIUM:
            SHT3X_WriteCommand(CMD_MEAS_CLOCKSTR_M);
            break;
        case REPEATAB_HIGH:
            SHT3X_WriteCommand(CMD_MEAS_CLOCKSTR_H);
            break;
        default:
            break;
    }
    SHT3X_ReadDataAndCrc(&hexTempValue, &hexHumiValue);
}

/**
 * @brief   init SHT3X, check device
 * @note    put at main init
 */
void SHT3X_InitBegin(void)
{
    uint8_t i = 0;

    SHT3X_StartPeriodicMeasurment(REPEATAB_HIGH, FREQUENCY_10HZ);
    for(i = 0; i < 9; i++)
    {
        DelayMs(110);
        SHT3X_ReadMeasurementBuffer();
        // SHT3X_GetTempAndHumiClkStretch(REPEATAB_LOW);

    }
    // SHT3X_StartPeriodicMeasurment(REPEATAB_LOW, FREQUENCY_HZ1);
    SHT3X_StartPeriodicMeasurment(REPEATAB_HIGH, FREQUENCY_10HZ);
}


// void main()
// {
//     SHT3X_InitBegin();
//     while(1)
//     {
//         SHT3X_ReadMeasurementBuffer();
//         UartSendStr("\r\nHT: ");
//         UartSendStr(TemperatureStr);
//         UartSendStr(" - ");
//         UartSendStr(HumidityStr);
//         DelayMs(2000);
//     }
// }

    // // declare 5byte group, last with '\0' for show
    // uint8_t Temperature[5] = {0, 0, '.', 0};
    // uint8_t Humidity[5] = {0, 0, '.', 0};
    // uint8_t TemperatureStr[5] = {0, 0, '.', 0};
    // uint8_t HumidityStr[5] = {0, 0, '.', 0};
    // uint8_t temperatureHexI = 0;    // integer
    // uint8_t temperatureHexD = 0;    // decimal
    // uint8_t humidityHexI = 0;
    // uint8_t humidityHexD = 0;
    // temperature = ((uint8_t)decTempValue << 8) + ((uint16_t)(decTempValue * 100) % 100);
    // humidity = ((uint8_t)decHumiValue << 8) + ((uint16_t)(decHumiValue * 100) % 100);

    // temperatureHexI = temperature >> 8;
    // temperatureHexD = temperature;
    // humidityHexI = humidity >> 8;
    // humidityHexD = humidity;
    // // todo higher than 100 or below 0
    // // todo only get origin data, do not change type here
    // // todo AHT20 deal the same, and change I2C function to standard
    // // if()
    // Temperature[0] = temperatureHexI / 10;
    // Temperature[1] = temperatureHexI % 10;
    // Temperature[3] = temperatureHexD / 10;
    // Humidity[0] = humidityHexI / 10;
    // Humidity[1] = humidityHexI % 10;
    // Humidity[3] = humidityHexD / 10;
    // TemperatureStr[0] = Temperature[0] + '0';
    // TemperatureStr[1] = Temperature[1] + '0';
    // TemperatureStr[3] = Temperature[3] + '0';
    // HumidityStr[0] = Humidity[0] + '0';
    // HumidityStr[1] = Humidity[1] + '0';
    // HumidityStr[3] = Humidity[3] + '0';



#endif /* __SHT3X_ATY_C */

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