The objective of this BSc diploma work is to design a PIC microcontroller based access control system.
To determine the requirements, I have made a detailed description of these entrance systems: CRYPTEX, SIMPLEX and POPULUS.
The designed access control system has a main unit, and a reader unit. These units communicate with radio data transfer. The main unit connects to the system only, when it is connected to a PC which runs the control program. Without the main unit, the access control works based on the reader unit’s database.
The system performs its tasks with an element of PIC18F microcontroller family, with the RFM12B radio transceiver, with an EEPROM memory, with a clock IC and with an FTDI chip.
The hardware section gives a detailed description about the used devices. It accents the supply circuits, because the designed system has different needs.
The next chapter deals with the software architecture. Scheduling the time controlled and event initiated tasks is made by the „round robin architect with interrupts”. I took the SW apart, into different levels. Each level has more modules. This makes possible the dynamic SW developing.
One separated chapter deals with practical troubleshooting of the designed units. The measured results and the test cases are presented too.
The PC’s control program has an own chapter. It is a “How to”, describes the function of it, and the GUI.
The study ends with a summary of the former chapters and the development possibilities.
The circuits layout drawings, the datasheets of the used devices and the implemented SW code are attached to the study on a CD.