WipperSnapper_I2C_Driver_DS2484.h

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#ifndef WipperSnapper_I2C_Driver_DS2484_H
#define WipperSnapper_I2C_Driver_DS2484_H

#define DS18B20_FAMILY_CODE 0x28         
#define DS18B20_CMD_CONVERT_T 0x44       
#define DS18B20_CMD_MATCH_ROM 0x55       
#define DS18B20_CMD_READ_SCRATCHPAD 0xBE 

#include "WipperSnapper_I2C_Driver.h"
#include <Adafruit_DS248x.h>

/**************************************************************************/
/**************************************************************************/
class WipperSnapper_I2C_Driver_DS2484 : public WipperSnapper_I2C_Driver {

public:
  /*******************************************************************************/
  /*******************************************************************************/
  WipperSnapper_I2C_Driver_DS2484(TwoWire *i2c, uint16_t sensorAddress)
      : WipperSnapper_I2C_Driver(i2c, sensorAddress) {
    _i2c = i2c;
    _sensorAddress = sensorAddress;
  }

  /*******************************************************************************/
  /*******************************************************************************/
  ~WipperSnapper_I2C_Driver_DS2484() { delete _ds2484; }

  /*******************************************************************************/
  /*******************************************************************************/
  bool begin() {
    // initialize DS2484
    _ds2484 = new Adafruit_DS248x();
    if (!_ds2484->begin(_i2c, (uint8_t)_sensorAddress)) {
      WS_DEBUG_PRINTLN("Could not find DS2484");
      return false;
    }

    // check bus is okay
    if (!_ds2484->OneWireReset()) {
      WS_DEBUG_PRINTLN("Failed to do a OneWire bus reset");
      if (_ds2484->shortDetected()) {
        WS_DEBUG_PRINTLN("\tShort detected");
      }
      if (!_ds2484->presencePulseDetected()) {
        WS_DEBUG_PRINTLN("\tNo presense pulse");
      }
      return false;
    }

    // locate first DS18B20
    bool found_device = false;
    _ds2484->OneWireReset();
    _ds2484->OneWireSearchReset();
    while (!found_device && _ds2484->OneWireSearch(_rom)) {
      if (_rom[0] == DS18B20_FAMILY_CODE) {
        found_device = true;
      } else {
        WS_DEBUG_PRINT("Found unwanted device with family code: 0x");
        WS_DEBUG_PRINTHEX(_rom[0]);
        WS_DEBUG_PRINTLN(" expected 0x28"); // DS18B20_FAMILY_CODE
      }
    }

    if (!found_device) {
      WS_DEBUG_PRINTLN("Could not find DS18B20 attached to DS2484");
      return false;
    }

    WS_DEBUG_PRINTLN("DS2484 found");
    return true;
  }

  /*******************************************************************************/
  bool processTemperatureEvent(sensors_event_t *tempEvent) {
    if (!_ds2484->OneWireReset()) {
      WS_DEBUG_PRINTLN("Failed to do a OneWire bus reset");
      return false;
    }
    if (!_ds2484->presencePulseDetected()) {
      tempEvent->temperature = NAN;
      return true;
    }

    _ds2484->OneWireWriteByte(DS18B20_CMD_MATCH_ROM); // Match ROM command
    for (int i = 0; i < 8; i++) {
      _ds2484->OneWireWriteByte(_rom[i]);
    }

    // Start temperature conversion
    _ds2484->OneWireWriteByte(DS18B20_CMD_CONVERT_T); // Convert T command
    delay(750); // Wait for conversion (750ms for maximum precision)

    // Read scratchpad
    if (!_ds2484->OneWireReset()) {
      WS_DEBUG_PRINTLN(
          "Failed to do a OneWire bus reset after starting temp conversion");
      return false;
    }
    _ds2484->OneWireWriteByte(DS18B20_CMD_MATCH_ROM); // Match ROM command
    for (int i = 0; i < 8; i++) {
      _ds2484->OneWireWriteByte(_rom[i]);
    }
    _ds2484->OneWireWriteByte(
        DS18B20_CMD_READ_SCRATCHPAD); // Read Scratchpad command

    uint8_t data[9];
    for (int i = 0; i < sizeof(data) / sizeof(data[0]); i++) {
      _ds2484->OneWireReadByte(&data[i]);
    }

    // Calculate temperature
    int16_t raw = (data[1] << 8) | data[0];
    tempEvent->temperature = (float)raw / 16.0;
    return true;
  }

  /*******************************************************************************/
  /*******************************************************************************/
  bool getEventAmbientTemp(sensors_event_t *tempEvent) {
    return processTemperatureEvent(tempEvent);
  }

protected:
  Adafruit_DS248x *_ds2484; 
  uint8_t _rom[8];          
};

#endif // WipperSnapper_I2C_Driver_DS2484