Real time operating systems have become an integral part of the embedded systems software. They play crucial role in allocating the available constrained resources efficiently. The resource can be anything like ALU in the processor, networking hardware, memory etc. The user program is broken into tasks and they will be competing for the resources. But in software RTOS, the RTOS itself has few tasks along with the user tasks which are resource hungry. So the resources are not confined to the user programs which reduce the efficiency of the overall system. The idea of implementing the RTOS in hardware itself comes here. Only the user program is to be programmed. The efficiency has increased drastically with some limitations. Here, a typical basic processor is developed. How the software RTOS effects the efficiency is discussed. Then the same processor is added to the hardware OS kernel. Scope of hybridization of RTOS is given which increases the efficiency to greater extent. The concept of hybridization is provided with an example and a programming environment for such hybrid RTOS is emphasized.

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Real Time Operating System Hardware Kernel Hybrid Rtos Hardware Scheduler Hardware Semaphore Manager