Design and implementation of a general : purpose transmitter based on microcontroller AT89C52

Abstract EN

-Design, implementation, and testing of a flexible and general-purpose transmitter is carried out.

A simple structure for the transmitter is defined to meet the hardware functional requirement of sensing the process variables, commanding actuators, and communicating with other control elements.

A personal computer represents a program development station and human interface to the transmitter so that it can be used to develop any application program of the RAM of a transmitter.

The basic hardware parts ot'the transmitter are the single chip microcontroller (AT89C52), the associated logic circuit, and iocai operator interaction panel.

However, the input and output structures may be changed according to the application requirements.

The hardware design is minimized to a single board.

The basic software functions comprise to two layers: the first is the system software, which turns the transmitter’s hardware into virtual high-level machinc.

It includes basic driver routines (AI/O, DI/O ...

etc) , control, and management software routines.

The second layer is the application layer, which depends on the transmitter’s basic system software.

Generally, the operating software of the transnmitter is designed as a single-user system consisting of two programs one is as a foreground program (interactive), which is interrupt driven, and the other is a background program which is the main program ofthe transmitter