jwilleke / DFRobot-DS18B20

A test and example Arduino code for DS18B20 Temperature Sensor

DS18B20 Temperature Sensor

Code use [OneWire]

Dallas Temperature Control Library vs DFRobot

We found the DallasTemperature-DS18B20 which uses the Dallas Temperature Control Library has more features and seems to be easier to use.

Device

We used this Gravity: Waterproof DS18B20 Temperature Sensor Kit

We statred with the code

SKU:DFR0198 Waterproof DS18B20 Sensor Wiki and added few things like getTempF(celsius) tp get Fahrenheit from Celsius value.

Expected Output

24.00 Celsius 75.20 Fahrenheit
24.00 Celsius 75.20 Fahrenheit
23.94 Celsius 73.40 Fahrenheit
23.87 Celsius 73.40 Fahrenheit
23.81 Celsius 73.40 Fahrenheit
23.75 Celsius 73.40 Fahrenheit

Arduino can not deal with high precision numbers

The float data type has only 6-7 decimal digits of precision. That means the total number of digits, not the number to the right of the decimal point. Unlike other platforms, where you can get more precision by using a double (e.g. up to 15 digits), on the Arduino, double is the same size as float.

We have been aunable to get any Celsius to Fahrenheit calculations to be accurate.