Development of an Arm Based Modbus RTU to TCP/IP Protocol Converter Using μC/OS II

In recent years, embedded technology has been rapidly developed and the embedded systems can adapt to strict demands of the supervisory control and data acquisition system in features, reliability, cost, size and power consumption etc. Using the embedded multi-MCU and high-speed dual-port RAM data sharing technology, communication protocol conversion equipment based on embedded multi- MCU and real-time multitasking operating system μC/OS-II has to be developed. With the help of RS232 or RS485 communication interfaces for lower machines such as data acquisition I/O modules, smart intelligent instruments and so on, the data is collected by this unit. Then, the data is transferred by Ethernet communication interface to remote monitoring systems such as Direct Attached Storage (DAS) or Distributed Control System (DCS). The functions of industrial communications network will be realized. Thus in this project the MODBUS/RTU to TCP/IP protocol conversion is focused mainly. The system has high reliability and real-time performance, and can facilitate the realization of data exchange, data sharing and information processing among embedded MCU’s.