MULTI-TASKING HARDWARE DESIGN: ELIMINATING OVERHEAD IN A MULTI-TASKING MICRO-CONTROLLER

摘要

Multi-tasking is normally a function of an operating system that requires significant overhead to switch between tasks. Embedded systems using microcontrollers typically rely on a Real-Time Operating System (RTOS) to provide multi-tasking capabilities. The implementation of multi-tasking hardware in a microcontroller significantly reduces the task-switching overhead and may eliminate the need for a RTOS. This paper describes the hardware design of a Multi-Tasking Micro-Controller Unit (MTMCU) and the improvements in both efficiency and simplicity over software implementations. In order to achieve hardware multi-tasking, the conc'ept of a Multi-Tasking Finite State Machine (MTFSM) is developed and explored. A general MTFSM-based design approach is developed and used to enhance a basic micro-controller design with multitasking capabilities. The enhanced design is then used to demonstrate the ability of a microprocessor to multi-task without the overhead required of software.