DallasTemperature.h

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#ifndef DallasTemperature_h
#define DallasTemperature_h

#define DALLASTEMPLIBVERSION "3.7.2" 

// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.

#ifndef REQUIRESNEW
#define REQUIRESNEW                                                            \
  false 
#endif

#ifndef REQUIRESALARMS
#define REQUIRESALARMS                                                         \
  true 
#endif

#include <OneWire.h>
#include <inttypes.h>

// Model IDs
#define DS18S20MODEL 0x10  
#define DS18B20MODEL 0x28  
#define DS1822MODEL 0x22   
#define MAX31850MODEL 0x3B 

// OneWire commands
#define STARTCONVO                                                             \
  0x44 
#define COPYSCRATCH 0x48     
#define READSCRATCH 0xBE     
#define WRITESCRATCH 0x4E    
#define RECALLSCRATCH 0xB8   
#define READPOWERSUPPLY 0xB4 
#define ALARMSEARCH 0xEC     

// Scratchpad locations
#define TEMP_LSB 0        
#define TEMP_MSB 1        
#define HIGH_ALARM_TEMP 2 
#define LOW_ALARM_TEMP 3  
#define CONFIGURATION                                                          \
  4 
#define INTERNAL_BYTE 5 
#define COUNT_REMAIN                                                           \
  6 
#define COUNT_PER_C 7 
#define SCRATCHPAD_CRC 8 

// Device resolution
#define TEMP_9_BIT 0x1F  
#define TEMP_10_BIT 0x3F 
#define TEMP_11_BIT 0x5F 
#define TEMP_12_BIT 0x7F 

// Error Codes
#define DEVICE_DISCONNECTED -127 

typedef uint8_t DeviceAddress[8]; 

class DallasTemperature {
public:
  DallasTemperature(OneWire *);

  void begin(void);

  uint8_t getDeviceCount(void);

  bool isConversionComplete(void);

  bool validAddress(uint8_t *);

  bool getAddress(uint8_t *, const uint8_t);

  bool isConnected(uint8_t *);

  bool isConnected(uint8_t *, uint8_t *);

  void readScratchPad(uint8_t *, uint8_t *);

  void writeScratchPad(uint8_t *, const uint8_t *);

  bool readPowerSupply(uint8_t *);

  uint8_t getResolution();

  void setResolution(uint8_t);

  uint8_t getResolution(uint8_t *);

  bool setResolution(uint8_t *, uint8_t);

  void setWaitForConversion(bool);
  bool getWaitForConversion(void);

  void setCheckForConversion(bool);
  bool getCheckForConversion(void);

  void requestTemperatures(void);

  bool requestTemperaturesByAddress(uint8_t *);

  bool requestTemperaturesByIndex(uint8_t);

  float getTempC(uint8_t *);

  float getTempF(uint8_t *);

  float getTempCByIndex(uint8_t);

  float getTempFByIndex(uint8_t);

  bool isParasitePowerMode(void);

  bool isConversionAvailable(uint8_t *);

#if REQUIRESALARMS

  typedef void AlarmHandler(uint8_t *);

  // sets the high alarm temperature for a device
  // accepts a char.  valid range is -55C - 125C
  void setHighAlarmTemp(uint8_t *, const char);

  // sets the low alarm temperature for a device
  // accepts a char.  valid range is -55C - 125C
  void setLowAlarmTemp(uint8_t *, const char);

  // returns a signed char with the current high alarm temperature for a device
  // in the range -55C - 125C
  char getHighAlarmTemp(uint8_t *);

  // returns a signed char with the current low alarm temperature for a device
  // in the range -55C - 125C
  char getLowAlarmTemp(uint8_t *);

  // resets internal variables used for the alarm search
  void resetAlarmSearch(void);

  // search the wire for devices with active alarms
  bool alarmSearch(uint8_t *);

  // returns true if ia specific device has an alarm
  bool hasAlarm(uint8_t *);

  // returns true if any device is reporting an alarm on the bus
  bool hasAlarm(void);

  // runs the alarm handler for all devices returned by alarmSearch()
  void processAlarms(void);

  // sets the alarm handler
  void setAlarmHandler(AlarmHandler *);

  // The default alarm handler
  static void defaultAlarmHandler(uint8_t *);

#endif

  static float toFahrenheit(const float);

  static float toCelsius(const float);

#if REQUIRESNEW

  // initalize memory area
  void *operator new(unsigned int);

  // delete memory reference
  void operator delete(void *);

#endif

private:
  typedef uint8_t ScratchPad[9];

  // parasite power on or off
  bool parasite;

  // used to determine the delay amount needed to allow for the
  // temperature conversion to take place
  uint8_t bitResolution;

  // used to requestTemperature with or without delay
  bool waitForConversion;

  // used to requestTemperature to dynamically check if a conversion is complete
  bool checkForConversion;

  // count of devices on the bus
  uint8_t devices;

  // Take a pointer to one wire instance
  OneWire *_wire;

  // reads scratchpad and returns the temperature in degrees C
  float calculateTemperature(uint8_t *, uint8_t *);

  void blockTillConversionComplete(uint8_t *, uint8_t *);

#if REQUIRESALARMS

  // required for alarmSearch
  uint8_t alarmSearchAddress[8];
  char alarmSearchJunction;
  uint8_t alarmSearchExhausted;

  // the alarm handler function pointer
  AlarmHandler *_AlarmHandler;

#endif
};
#endif