graphical interface for measuring and recording temperature with the ds18b20 digital output sensor

The article presents the authors’ two originalgraphical interfaces made in Borland Delphi anddesigned to measure and record (with the DS18B20sensor) a wide range of negative and positivetemperatures. The first interface allows the readingof a sensor’s unique code and then themeasurement and recording of temperature. Thesecond interface can work with a variable numberof such sensors once their unique code has beenentered.The interfaces have been conceived for thestudy of the slow variations of air temperatureinside chambers or wood, in timber freezing,heating or drying processes.To achieve the purpose we have alsoexperimented on other variants of temperaturesensors, but finally we have adopted the variantthat uses the DS18B20 digital output sensormanufactured by Dallas Company. This sensor hasthe following advantages:- a small size (it can be easily inserted into a 4mm diameter hole made in the wood piece);- it measures temperatures between -55°Cand +125°C;- it can relatively easily connect to the RS232serial port of a computer;- with only two wires one can ensure datainsertion and transmission from a numberof 4 ÷ 10 sensors of this type.