ITEC 625 Computer Systems Architecture Midterm Exam Answers
I. For each statement below, Explain Why it is True or False (2 points each, 1 point for correct answer of True or False, another 1 point for explanation)
1) Secondary storage is often equated with main memory in von Neumann architecture.
2) Program execution consists of repeating the process of instruction fetch and instruction execution.
3) Addition and subtraction can be performed on numbers in two’s complement notation by treating them as unsigned integers.
4) One drawback of sign-and-magnitude representation is that there are two representations of 0.
5) Both sign-and-magnitude representation and twos complement representation use the most significant bit as a sign bit
6) When you want to represent -0.0000000000001 as an 8-bit float point number but the float point system cannot represent it due to limit of bits, you have a negative overflow.
7) The value of an unsigned integer is interpreted as the magnitude of its underlying binary pattern.
8) RISC systems typically have a small ISA (fewer instructions) but make up for it with faster hardware.
9) ALU reads the instructions, and generates the necessary digital signals to operate the other components.
10) Superscalar architectures allow several instructions to be issued and completed per clock cycle.
II. Multiple Choices – Choose ONLY 1 Answer (2 points each, 20 points total)
III. Short Answers (2 points each, 12 points total)
IV. 2’s Complement (3 points each, 12 points total)
The following are 2’s complement numbers, note they are binary numbers of four bits. Calculate the number expressions, and tell whether there is an overflow. Use binary and decimal calculation to prove your answer.
V. For an m-bit binary integer number, what is the largest positive number and what is the smallest negative number (i.e. negative number with largest absolute value) that it can represent? Please prove your answer. (4 points)
VI. For the following IEEE 754 format numbers, write out the equivalent decimal numbers (Please show your calculation steps). (4 points each, total 8 points)
VII. Each row in the following table contains the same number in different number formats, namely binary, octal, decimal, and hexadecimal. Please fill out the missing numbers, and use 12-bit 2’s complement for negative binary values. (1 point for each answer in a blank space)
Using the Little Man Computer and Instruction Set, answer the following questions: