For days now ..trying to get the temperature from a DS18B20. I need help...lol
There are many examples on how to search for wire but it’s not what I want to do. I want to get the temp with the address of the device. I want to insert the address myself in the code. I’m new here so it has to be simple no print function or complex stuff. I’d like to put the temperature is a variable like “temp1” there must be a simple way to do this...
Can someone guide me, please
Thanks
Julien
I'm trying to understand this code (example with the Dallas library)with no luck.
how to get temp with a know device address..insideThermometer and outsideThermometer
this is not very clear how to do it..
thanks for your help.
#include <OneWire.h>
#include <DallasTemperature.h>
// Data wire is plugged into port 2 on the Arduino
#define ONE_WIRE_BUS 2
#define TEMPERATURE_PRECISION 9
// Setup a oneWire instance to communicate with any OneWire devices (not just Maxim/Dallas temperature ICs)
OneWire oneWire(ONE_WIRE_BUS);
// Pass our oneWire reference to Dallas Temperature.
DallasTemperature sensors(&oneWire);
// arrays to hold device addresses
DeviceAddress insideThermometer, outsideThermometer;
void setup(void)
{
// start serial port
Serial.begin(9600);
Serial.println("Dallas Temperature IC Control Library Demo");
// Start up the library
sensors.begin();
// locate devices on the bus
Serial.print("Locating devices...");
Serial.print("Found ");
Serial.print(sensors.getDeviceCount(), DEC);
Serial.println(" devices.");
// report parasite power requirements
Serial.print("Parasite power is: ");
if (sensors.isParasitePowerMode()) Serial.println("ON");
else Serial.println("OFF");
// assign address manually. the addresses below will beed to be changed
// to valid device addresses on your bus. device address can be retrieved
// by using either oneWire.search(deviceAddress) or individually via
// sensors.getAddress(deviceAddress, index)
//insideThermometer = { 0x28, 0x1D, 0x39, 0x31, 0x2, 0x0, 0x0, 0xF0 };
//outsideThermometer = { 0x28, 0x3F, 0x1C, 0x31, 0x2, 0x0, 0x0, 0x2 };
// search for devices on the bus and assign based on an index. ideally,
// you would do this to initially discover addresses on the bus and then
// use those addresses and manually assign them (see above) once you know
// the devices on your bus (and assuming they don't change).
//
// method 1: by index
if (!sensors.getAddress(insideThermometer, 0)) Serial.println("Unable to find address for Device 0");
if (!sensors.getAddress(outsideThermometer, 1)) Serial.println("Unable to find address for Device 1");
// method 2: search()
// search() looks for the next device. Returns 1 if a new address has been
// returned. A zero might mean that the bus is shorted, there are no devices,
// or you have already retrieved all of them. It might be a good idea to
// check the CRC to make sure you didn't get garbage. The order is
// deterministic. You will always get the same devices in the same order
//
// Must be called before search()
//oneWire.reset_search();
// assigns the first address found to insideThermometer
//if (!oneWire.search(insideThermometer)) Serial.println("Unable to find address for insideThermometer");
// assigns the seconds address found to outsideThermometer
//if (!oneWire.search(outsideThermometer)) Serial.println("Unable to find address for outsideThermometer");
// show the addresses we found on the bus
Serial.print("Device 0 Address: ");
printAddress(insideThermometer);
Serial.println();
Serial.print("Device 1 Address: ");
printAddress(outsideThermometer);
Serial.println();
// set the resolution to 9 bit
sensors.setResolution(insideThermometer, TEMPERATURE_PRECISION);
sensors.setResolution(outsideThermometer, TEMPERATURE_PRECISION);
Serial.print("Device 0 Resolution: ");
Serial.print(sensors.getResolution(insideThermometer), DEC);
Serial.println();
Serial.print("Device 1 Resolution: ");
Serial.print(sensors.getResolution(outsideThermometer), DEC);
Serial.println();
}
// function to print a device address
void printAddress(DeviceAddress deviceAddress)
{
for (uint8_t i = 0; i < 8; i++)
{
// zero pad the address if necessary
if (deviceAddress[i] < 16) Serial.print("0");
Serial.print(deviceAddress[i], HEX);
}
}
// function to print the temperature for a device
void printTemperature(DeviceAddress deviceAddress)
{
float tempC = sensors.getTempC(deviceAddress);
Serial.print("Temp C: ");
Serial.print(tempC);
Serial.print(" Temp F: ");
Serial.print(DallasTemperature::toFahrenheit(tempC));
}
// function to print a device's resolution
void printResolution(DeviceAddress deviceAddress)
{
Serial.print("Resolution: ");
Serial.print(sensors.getResolution(deviceAddress));
Serial.println();
}
// main function to print information about a device
void printData(DeviceAddress deviceAddress)
{
Serial.print("Device Address: ");
printAddress(deviceAddress);
Serial.print(" ");
printTemperature(deviceAddress);
Serial.println();
}
void loop(void)
{
// call sensors.requestTemperatures() to issue a global temperature
// request to all devices on the bus
Serial.print("Requesting temperatures...");
sensors.requestTemperatures();
Serial.println("DONE");
// print the device information
printData(insideThermometer);
printData(outsideThermometer);
}
I suspect you are not getting a proper explanation of the system. You are not the first to suffer this. You need two programmes, one to get the addresses and the other to do the job using those addresses. Ditch that code and try this.
http://www.hacktronics.com/Tutorials/arduino-1-wire-tutorial.html
Have a positive means of identifying the sensors, like a mark on the plug, or a sticky label.
Thank You very much.
it working...i just have to figure a way to do all the reading and store them in an array....i will try to figure that out.
thanks again
Julien250:
..i just have to figure a way to do all the reading and store them in an array..
I wouldn't bother.
If you really feel you have to do this, there are already several examples available.