the search() function searches for devices on the 1 Wire bus
Once all the devices have been found, the reset_search() function is used to restart the process. With the search() function, we search for all the devices on the bus and print the temperature data on the serial monitor in the manner known from the previous example. In the loop() cycle, we use the search(addr) function of the OneWire library to find the devices on the 1 Wire bus. The address of the found device is stored in the search() function parameter, in the addr array. To use multiple DS18B20 sensors, we need to know each sensor’s unique address. This is important because when using 1 Wire communication the Arduino needs to know which sensor it is polling. DS18B20 sensors have a unique 64-bit address that is assigned to the sensors at the factory. To get unique addresses, we use the search() function of the OneWire library in the following example. The above code can only be used to query a single DS18B20. Let’s see what happens if we want to connect several sensors to the 1 Wire bus. Then we print the temperature on the serial monitor the measured temperature can be found in this memory area the measurement takes a maximum of 750ms. According to the data sheet, with a resolution of 12 bits, During the measurement, the ds18b20 is busy and does not accept commands Waiting for the measurement to finish. the sensing device is powered by parasitic power. Adding a second parameter indicates that The Convert T command starts the temperature conversion. This command can only be used if there is only one DS18B20 on the bus. unique 48-bit serial number, and 8-bit CRC. This command allows the bus master to read 1 Wire bus reset,this is required before starting communication And you also need an array to read the ROM We create an array for the data read from Scratchpad Arduino pin 10 is the data line of the 1 Wire bus
In the following example, we read a DS18B20 temperature sensor with Arduino on the 1 Wire bus.
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