X86 System Protection Mode To Achieve Optimized

Protected mode is a particular protect strategy in Intel (IA-32), it's also introduced by commerce processor rarely. Researching and implementing the protected mode is one of the difficulties in compatible micro-processor design. The work of this thesis is supported by the National Advanced Research Project.The author took part in the design of embedded micro-processor "Longtium C2".This paper analysed the fuction of IA-32 protected mode, confirmed the function that LongtiumC2 would implement, designed the implement stategy of the protected mode, implemented the LongtiumC2 and completed the verification of protected modeThe research work of this paper mainly includes:1. Studied the fuction of IA-32 protected mode, including three working modes, address transform mechanism, task management mechanism and exception debugging mechanism.Comfirmed the fuction of LongtiumC2 protected mode.2. Analysed the microoperation of the 486 protected mode instructions, comfirmed the protected mode instruction implement method and processor's pipeline architecture.3. Took part in LongtiumC2's architecture and pipeline design, divided the protected mode functions into the functional modules, designed the microinstruction's format.4. Basing on the fuction of pipeline and the format of microinstruction, transformed and optimized the instruction's microoperations into the microinstructions, and studied the key arithmetic of the instructions.5. Designed the test strategy for testing the protected mode, build the protected mode test envirment and programmer model, studied how to coverage full fuctions .Wrote DOS test programmes.The dissertation does some research about 32-bit embedded micro- processor architecture supporting protected mode, The research work offers design considerations and technological reserves for higher performance microprocessor designs with x86 architectures...