Minufiya University Faculty of Electronic Engineering Computer Science and Engineering

‫ﺟﺎﻣﻌ ﺔ اﻟﻤﻨﻮﻓﻴ ﺔ‬

Computer Architecture Third Year First Semester (2011-2012)

Sheet: 2 [1] What are the differences between Hardwired and Hardware/software approaches? [2] What are the main components of the CPU? Briefly describe the functions of each component. [3] Show the internal structure of the CPU? [4] What are the categories of the CPU registers? Who can access each category? [5] What are the roles of the CPU registers? [6] What are the categories of user-visible registers? Describe the functions of each category. [7] What are the different types of address registers? Describe the function of each type. [8] List the different types of control and statues registers and briefly describe the function of each type. [9] What is the status register? Write a short description of the main flags in a status register and the function of each flag. [10] Consider a hypothetical CPU that generates a 24-bit address (that is, the program counter and the address bus are 24-bits wide) and has a 16-bit data bus. (a) What is the maximum memory data space that the CPU can access directly if it is connected to a “16-bit memory”? (b) What amount of memory data space (in part a), if this memory is “byte addressable”? (c) What is the maximum memory data space that the CPU can access directly if it is connected to an “8-bit memory”? (d) Would it be possible to connect a “32-bit memory’ to this CPU/bus arrangement? If yes, describe how to do it. If no, describe why not. (e) What architectural features would be needed to allow this CPU to access a separate “I/O address space”? (f) Describe two approaches to provide the control signals for part (e). [11] Briefly describe the main registers of the microprocessors 8086, 80386 and MC 68000. [12] What is the function of the following registers: PC, IR, MAR, MBR, I/O AR, I/O BR and DR? [13] What are the general categories of functions specified by computer instructions?

[14] Briefly describe the different phases of an instruction cycle. [15] Briefly describe the possible states that define an instruction cycle. [16] The hypothetical machine of Figure 2.4 has two I/O instructions: 0011 = Load AC from I/O 0111 = Store AC to I/O In these cases, the 12-bit address identifies a particular I/O device. Show the program execution (using the format of Figure 2.5) for the following program: 1. Load AC from device 5. 2. Add contents of memory location 940. 3. Store AC to device 6. Assume that the next value retrieved from device 5 is 3 and that location 940 contains a value of 2. [17] What are the different classes of Interrupts? [18] By using a simple example of printing data, show the timing diagram that describes the effect of interrupts on processing efficiency. [19] Briefly describe the different phases of an instruction cycle with interrupts. [20] Briefly describe the possible states that define an instruction cycle with interrupts. [21] By using state diagram, show how the indirect cycle can be included in the instruction cycle. [22] What is the main purpose of pipelining? Show the timing diagram of 6 stage pipelines.

« With my best wishes » Dr. Gamal M. Attiya