uint8_t DallasTemperature::getResolution(const uint8_t* deviceAddress) {
// this model has a fixed resolution of 9 bits but getTemp calculates
// a full 12 bits resolution and we need 750ms convert time
if (isDS18S20Model(deviceAddress)) return 12;
ScratchPad scratchPad;
if (readScratchPadCRC(deviceAddress, scratchPad)) {
#if REQUIRESONLY12BITCONVERSION
return 12;
#else
switch (scratchPad[CONFIGURATION]) {
case TEMP_12_BIT:
return 12;
case TEMP_11_BIT:
return 11;
case TEMP_10_BIT:
return 10;
case TEMP_9_BIT:
return 9;
}
#endif
}
return 0;
}
bool DallasTemperature::setResolution(const uint8_t* deviceAddress, uint8_t newResolution) {
ScratchPad scratchPad;
if (readScratchPadCRC(deviceAddress, scratchPad)) {
// DS18S20 has a fixed 9-bit resolution
if (!isDS18S20Model(deviceAddress)) {
uint8_t resolution;
#if REQUIRESONLY12BITCONVERSION
resolution = TEMP_12_BIT;
#else
switch (newResolution) {
case 12:
resolution = TEMP_12_BIT;
break;
case 11:
resolution = TEMP_11_BIT;
break;
case 10:
resolution = TEMP_10_BIT;
break;
case 9:
default:
resolution = TEMP_9_BIT;
break;
}
#endif
scratchPad[CONFIGURATION] = resolution;
writeScratchPad(deviceAddress, scratchPad, false);
}
return true; // new value set
}
return false;
}
void DallasTemperature::setLowAlarmTemp(const uint8_t* deviceAddress, char celsius) {
// make sure the alarm temperature is within the device's range
if (celsius > 125) celsius = 125;
else if (celsius < -55) celsius = -55;
ScratchPad scratchPad;
if (readScratchPadCRC(deviceAddress, scratchPad)) {
scratchPad[LOW_ALARM_TEMP] = (uint8_t) celsius;
writeScratchPad(deviceAddress, scratchPad, true);
}
}
int16_t DallasTemperature::getTempRaw(const uint8_t* deviceAddress) {
ScratchPad scratchPad;
if (!readScratchPadCRC(deviceAddress, scratchPad)) {
return DEVICE_DISCONNECTED;
}
// return DEVICE_DISCONNECTED when a reset has been detected to force it to be reconfigured
if (detectedReset(scratchPad)) {
return DEVICE_DISCONNECTED;
}
return calculateTemperature(deviceAddress, scratchPad);
}
bool DallasTemperature::hasAlarm(const uint8_t* deviceAddress) {
ScratchPad scratchPad;
if (readScratchPadCRC(deviceAddress, scratchPad)) {
float temp = calculateTemperature(deviceAddress, scratchPad);
// check low alarm
if ((char) temp <= (char) scratchPad[LOW_ALARM_TEMP]) return true;
// check high alarm
if ((char) temp >= (char) scratchPad[HIGH_ALARM_TEMP]) return true;
}
// no alarm
return false;
}
bool DallasTemperature::initConnection(const uint8_t* deviceAddress) {
#if REQUIRESRESETDETECTION
ScratchPad scratchPad;
bool writeSettings = false;
if (isParasitePowered(deviceAddress)) {
return false;
}
// Reload settings from EEPROM so we can skip writing EEPROM if the values are already set
recallScratchpad(deviceAddress);
if (!readScratchPadCRC(deviceAddress, scratchPad)) {
return false;
}
#if REQUIRESONLY12BITCONVERSION
if(scratchPad[CONFIGURATION] != TEMP_12_BIT){
scratchPad[CONFIGURATION] = TEMP_12_BIT;
writeSettings = true;
}
#endif
// Make sure that HIGH_ALARM_TEMP is set to zero in EEPROM
// This value will be loaded on power on
if (scratchPad[HIGH_ALARM_TEMP]) { // conditional to avoid wear on eeprom.
scratchPad[HIGH_ALARM_TEMP] = 0;
writeSettings = true;
}
if (writeSettings){
writeScratchPad(deviceAddress, scratchPad, true); // save settings to eeprom
}
// Write HIGH_ALARM_TEMP again, but don't save to EEPROM, so that it reverts to 0 on reset
// from this point on, if we read a scratchpad with a 0 value in HIGH_ALARM (detectedReset() returns true)
// it means the device has reset or the previous write of the scratchpad above was unsuccessful.
// Either way, initConnection() should be called again
scratchPad[HIGH_ALARM_TEMP] = 1;
writeScratchPad(deviceAddress, scratchPad, false);
#endif
return true;
}
char DallasTemperature::getLowAlarmTemp(const uint8_t* deviceAddress) {
ScratchPad scratchPad;
if (readScratchPadCRC(deviceAddress, scratchPad)) return (char) scratchPad[LOW_ALARM_TEMP];
return DEVICE_DISCONNECTED_C;
}
