GY-63_MS5611/libraries/DS18B20/DS18B20.cpp

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//
// FILE: DS18B20.cpp
// AUTHOR: Rob.Tillaart@gmail.com
// VERSION: 0.1.0
// DATE: 2017-07-25
//
// PUPROSE: library for DS18B20 temperature sensor with minimal footprint
//
// HISTORY:
// 0.1.0 = 2017-07-25 initial version
#include "Arduino.h"
#include "DS18B20.h"
// OneWire commands
#define STARTCONVO 0x44
#define READSCRATCH 0xBE
#define WRITESCRATCH 0x4E
// 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 // 9 bit
#define TEMP_10_BIT 0x3F // 10 bit
#define TEMP_11_BIT 0x5F // 11 bit
#define TEMP_12_BIT 0x7F // 12 bit
DS18B20::DS18B20(OneWire* _oneWire)
{
_wire = _oneWire;
}
bool DS18B20::begin(void)
{
_wire->reset_search();
_wire->search(deviceAddress);
return (_wire->crc8(deviceAddress, 7) == deviceAddress[7]);
}
void DS18B20::readScratchPad(uint8_t *scratchPad, uint8_t fields)
{
_wire->reset();
_wire->select(deviceAddress);
_wire->write(READSCRATCH);
for(uint8_t i=0; i < fields; i++)
{
scratchPad[i] = _wire->read();
}
_wire->reset();
}
bool DS18B20::isConversionComplete(void)
{
return (_wire->read_bit() == 1);
}
void DS18B20::requestTemperatures(void)
{
_wire->reset();
_wire->skip();
_wire->write(STARTCONVO, 0);
}
float DS18B20::getTempC(void)
{
ScratchPad scratchPad;
readScratchPad(scratchPad, 2);
int16_t rawTemperature = (((int16_t)scratchPad[TEMP_MSB]) << 8) | scratchPad[TEMP_LSB];
float temp = 0.0625 * rawTemperature;
if (temp < -55) return DEVICE_DISCONNECTED;
return temp;
}
void DS18B20::setResolution(uint8_t newResolution)
{
_wire->reset();
_wire->select(deviceAddress);
_wire->write(WRITESCRATCH);
// two dummy values for LOW & HIGH ALARM
_wire->write(0);
_wire->write(100);
switch (newResolution)
{
case 12:
_wire->write(TEMP_12_BIT);
break;
case 11:
_wire->write(TEMP_11_BIT);
break;
case 10:
_wire->write(TEMP_10_BIT);
break;
case 9:
default:
_wire->write(TEMP_9_BIT);
break;
}
_wire->reset();
}
// END OF FILE