Abstract: Currently the programming method of single-chip microcontroller really faced big challenge owing to more and more complex requirement of application,therefore it is a better choice using this programming method under supporting of real-time operating system than conventional programming method.This paper researched corresponding programming method of the embedded application and working process of RTX51 Tiny,which is a real-time multitask operating system.In addition gives application instance and problems which should be paid attention to during development.