Software calibration: a view on a linear deviation concept

The development of a specialized circuit for measurement and recording (essentially a microcontroller with a masked ROM containing a specialized program) is described. The software calibration method is based on the assumption of a linear deviation from the nominal law. The purpose of this approach is to offer for loggers an architecture as universal as possible and also to simplify the task of the designer in charge of a new development. The example of a temperature and humidity recorder illustrates the features and limitations of the method, as well as some precautions to be taken. The work considered was carried out in the framework of a large project devoted to the design optimization of portable, autonomous micro-data-loggers recording various physical parameters