The Design And Realization Of Embedded Programming Logical Controller Based On ATMEGA169

This paper is designed a system based on AVR microcontroller ATMEGA169, it integrated use of embedded microcontroller technology, the traditional PLC technology and computer technology. The system is not only completed the basis of the traditional PLC functions, but also have a compact structure and low cost, it can satisfy the user's individual requirements.The paper mainly include three parts: general design of embedded PLC, hardware circuit design and software design. Firstly, the general design, The paper proposed overall structure of the embedded PLC system design based on the full study of traditional PLC internal structure and working principle. Secondly, the hardware circuit design with ATMEGA169 as the core, it integrated the common sensors signal transmitter circuit in the core control circuit board and it designed more multi-channel analog acquisition; And the communication module of the system introducted the reliable CAN interface, using Modbus protocol, improve the system of communication distance, speed and reliability. The HCI module could achieve a real-time monitoring and controlling of the system with the methods of combined using button, LED and LCD. Thirdly, the SCM system program design, it uses modular design method. The system program module consists of the main program design, I/O module program design, HCI module program design, fault detection program design and the communication program design; Finally, The paper designed a ladder diagram integrated development environment based on Borland C++ Builder platform, with this design the ladder diagram can realize the functions of draw, edit, save and compile. It's a useful try and explore to improve the standardization and generic of ladder software.This paper completed the production of circuit boards, and completed the main module debug of systems hardware and software, it verification the reasonable and feasible of the Embedded PLC system design. The research of this paper settle the foundation for the new embedded PLC technology with independent property rights .