Inherent characteristic of an embedded system is it is tightly constrained system. To meet such design and implementation challenge, special purpose hardware and software is needed. In this scenario, ARM processor architecture along with RTOS provides best possible choice for system design and implementations. In most of the industrial applications, MODBUS protocol is commonly employed for communication among various devices. The work described in this paper consists of realization of MODBUS protocol using µCOS-II RTOS on ARM 7 processor (LPC 2148). The protocol has been implemented and system is tested successfully. The paper also presents the test results of the work carried out.

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ARM RTOS MODBUS