Hardware Implementation Of Real Time Operating System Task Scheduling Algorithm

Real-time operating system plays an important role in the embedded systems, controls the work and operation of the whole system. The merits of a performance of real-time operating system have a direct impact on all the performance of the system.Existing real-time operating system kernel is the software that is added to applications. It not only increases the amount of storage space, increases applications of additional load.especially in a strong real-time occasion. Response to processing tasks within the time limit has become a basic requirement for real-time operating system.Overhead for real-time operating system cause the application to reduce the enforceability.Only improving scheduling algorithms can not make real-time increased significantly. So this paper proposed hardware real-time operating system FPGA-based design. Real-time operating system kernel is hardened to the FPGA platform. As a separate hardware module execute in parallel with the processor.Established by the interrupt controller, input/output registers and real-time task management module of the overall structure of the hardware real-time operating system. The main working process: Through the data bus to send the appropriate commands and parameters to a specific hardware logic unit input registers, hardware logic units take appropriate actions, and the results are sent to the corresponding output registers for the CPU to read.In this paper, embedded real time operating systemμC/OS-Ⅱuses as the research object. Modify theμC/OS-Ⅱin the data structure by the software.According to the parallelism features of the hardware logic, build each module of the hardware logical structure. The whole design utilizes VHDL hardware description language to describe each function module.Using Xilinx's ISE 8.2 software to analysis system debugging, to complete function simulation.In this paper, design and implement the hardware logic for the task management module and the semaphore management module. Task management module improves and hardens theμC/OS-Ⅱtask scheduling algorithm.Based on the uC/OS-Ⅱkernel original priority-based preemptive scheduling algorithm. Extend the same priority task scheduling algorithm.Remove the requirement for each task of the original system having a different priority. Use hardware logic to implement the real-time operating system task management module, deterministic and real-time are improved significantly. Give full play to the potential multi-task parallelism. Analysis and improve the semaphore management and application ofμC/OS-Ⅱ. Design and implement the hardware logic for semaphore management module.Reduce the overhead for frequently look-up table and access memory. Make scheduling function of real-time operating system from pure software into hardware to implement, it greatly improves real-time and processing of the real-time operating system.