/*

* Copyright 2012-2013 BrewPi/Elco Jacobs.

* Copyright 2013 Matthew McGowan.

*

* This file is part of BrewPi.

*

* BrewPi is free software: you can redistribute it and/or modify

* it under the terms of the GNU General Public License as published by

* the Free Software Foundation, either version 3 of the License, or

* (at your option) any later version.

*

* BrewPi is distributed in the hope that it will be useful,

* but WITHOUT ANY WARRANTY; without even the implied warranty of

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

* GNU General Public License for more details.

*

* You should have received a copy of the GNU General Public License

* along with BrewPi. If not, see <http://www.gnu.org/licenses/>.

*/

#include "Brewpi.h"

#include "OneWireTempSensor.h"

#include "DallasTemperature.h"

#include "OneWire.h"

#include "OneWireDevices.h"

#include "PiLink.h"

#include "Ticks.h"

#include "TemperatureFormats.h"

OneWireTempSensor::~OneWireTempSensor(){

delete sensor;

};

/**

* Initializes the temperature sensor.

* This method is called when the sensor is first created and also any time the sensor reports it's disconnected.

* If the result is TEMP_SENSOR_DISCONNECTED then subsequent calls to read() will also return TEMP_SENSOR_DISCONNECTED.

* Clients should attempt to re-initialize the sensor by calling init() again.

*/

bool OneWireTempSensor::init(){

// save address and pinNr for log messages

char addressString[17];

printBytes(sensorAddress, 8, addressString);

DEBUG_ONLY(uint8_t pinNr = oneWirePin);

bool success = false;

if (sensor==NULL) {

sensor = new DallasTemperature(oneWire);

if (sensor==NULL) {

logErrorString(ERROR_SRAM_SENSOR, addressString);

}

}

logDebug("init onewire sensor");

// This quickly tests if the sensor is connected and initializes the reset detection.

// During the main TempControl loop, we don't want to spend many seconds

// scanning each sensor since this brings things to a halt.

if (sensor && sensor->initConnection(sensorAddress) && requestConversion()) {

logDebug("init onewire sensor - wait for conversion");

waitForConversion();

temperature temp = readAndConstrainTemp();

DEBUG_ONLY(logInfoIntStringTemp(INFO_TEMP_SENSOR_INITIALIZED, pinNr, addressString, temp));

success = temp!=DEVICE_DISCONNECTED && requestConversion();

}

setConnected(success);

logDebug("init onewire sensor complete %d", success);

return success;

}

bool OneWireTempSensor::requestConversion()

{

bool ok = sensor->requestTemperaturesByAddress(sensorAddress);

setConnected(ok);

return ok;

}

void OneWireTempSensor::setConnected(bool connected) {

if (this->connected==connected)

return; // state is stays the same

char addressString[17];

printBytes(sensorAddress, 8, addressString);

this->connected = connected;

if(connected){

// TODO - fix the following to use the defined OneWire pin

// logInfoIntString(INFO_TEMP_SENSOR_CONNECTED, 0, addressString);

// logInfoIntString(INFO_TEMP_SENSOR_CONNECTED, this->oneWire->pinNr(), addressString);

}

else{

// TODO - fix the following to use the defined OneWire pin

// logWarningIntString(WARNING_TEMP_SENSOR_DISCONNECTED, 0, addressString);

// logWarningIntString(WARNING_TEMP_SENSOR_DISCONNECTED, this->oneWire->pinNr(), addressString);

}

}

temperature OneWireTempSensor::read(){

if (!connected)

return TEMP_SENSOR_DISCONNECTED;

temperature temp = readAndConstrainTemp();

requestConversion();

return temp;

}

temperature OneWireTempSensor::readAndConstrainTemp()

{

temperature temp = sensor->getTempRaw(sensorAddress);

if(temp == DEVICE_DISCONNECTED){

setConnected(false);

return TEMP_SENSOR_DISCONNECTED;

}

const uint8_t shift = TEMP_FIXED_POINT_BITS-ONEWIRE_TEMP_SENSOR_PRECISION; // difference in precision between DS18B20 format and temperature adt

temp = constrainTemp(temp+calibrationOffset+(C_OFFSET>>shift), ((int) MIN_TEMP)>>shift, ((int) MAX_TEMP)>>shift)<<shift;

return temp;

}