嵌入式微处理器NCS多任务管理单元MTU的研究

STUDY ON MULTITASK MANAGEMENT UNIT MTU OF EMBEDDED MICROPROCESSOR NCS

确立了多任务管理单元 MTU的设计方案 ,探讨了多任务管理的定义、数据结构 ,给出了微处理器多任务切换算法 ,提出了多任务管理单元 MTU细胞群结构。细胞群结构由细胞组成 ,每个细胞可进行一种测试并输出测试的布尔值给微程序控制器来控制微程序的转移。多任务管理单元 MTU的 RTL级 VHDL描述经 EDA工具 MENTOR GRAPHICS的综合与仿真验证了多任务管理单元 RTL级 VHDL描述的正确性与有效性。

Multitask management unit (MTU) is a test unit which implements multitask management in a protected mode in microprocessors, and provides hardware support for tasks switch in microprocessor level. Firstly, a scheme for MTU is established, based on the scheme tasks switch algorithm given to switch tasks. Secondly, by analyzing the data structure and definition for multitask management, a kind of cell group architecture for MTU is put forward. The architecture consists of cells, each of which processes a kind of test and outputs Boolean value to microprogram controller. So an aim is achieved that the Boolean value of cell test in MTU may control microprogram branch. At last, the VHDL description of RTL level of MTU has been synthesized and simulated successfully in MENTOR GRAPHICS of EDA tools and its results of simulation prove MTU valid.