Abstract: In order to solve the problem of bad compatibility between monitoring and control network of coal mine and the third party equipments,the paper proposed a design scheme of embedded multi-bus communication protocol converter.It expounded contents of software part of the scheme emphatically,namely implementation of porting μC/OS-Ⅱ real-time operating system to AT91M40800,and pointed out the problems that should be paid attention to in the porting process as well as solution methods.At last it programmed testing codes.The software had been ported in the circuit board developed by our research group,the running application showed that the system is steady and reliable under multi-task environment.