Subject: Microprocessor and Microcontroller

[7] (b) Suppose, Pentium IV microprocessor operates in protected mode on Windows OS. To perform read or write operation every microprocessor needs to calculate physical address of RAM/ROM & in protected mode the segment register and descriptor table are used for this purpose. Now consider the following scenario: 1. Define a segment (DS/CS/SS/ES) limit so that system use maximum 1MB area of the RAM. 2. You must define descriptor privilege level of access right portion so that segment access will be granted. 3. Set a bit of access right portion that ensure CS (code segment) has valid address & limit. Also ensure descriptor describes code segment portion. 4. Here, confirm that code segment working through the privilege level that was previously defined as well as define a bit in access right portion that ensures if necessary code segment may be read. 5. You must define a bit in the descriptor so that segment extension feature will be accepted. 6. There will be a bit in the descriptor, which will ensure that microprocessor used 32-bit instructions mode because of working in Windows OS. Page 2 7. For the confirmation of Pentium IV working with 32-bit compatibility mode, there also define a bit in the descriptor. Also, ensure that code segment (CS) is available. Your task is to define 64 bits of the descriptor format used for Pentium IV microprocessor. Also, analyze the details of each bit so that above operations will perform correctly