COMP9601
Assignment 2 (individual assessment)
Due Date: 11 May, 11.59.59 pm

Question 1: (10%)
Is it possible to improve the CPU throughput by decreasing the average number of clock cycles per
instruction? What is the impact of decreasing this average number (cycle/instruction) by 30% on the
CPU performance? Explain your answer.

Question 2: (10%)
What is the maximum size of an addressable physical memory when the length of the physical address
is 16 bits and
a) the system is byte addressable?
b) the system is word addressable?

Question 3: (10%)
After storing the hexadecimal number 0F3E546A in the address range 134A-134D of a byte addressable
main memory, what is the value of each memory unit
a) when the little-endian format is used?
b) when the big-endian format is used?

Question 4: (20%)
For the postfix expression XY+YZ×+XZ+
a) write the assembly code can be used for implementation in the stack ISA.
b) write the assembly code can be used for the one-address ISA (like VSC) (by converting to an
infix expression).

Question 5: (10%)
In a byte-addressable system with 16-bit instruction, 12 registers and 2KB of main memory,
a) what is the maximum number of operation codes (opcodes) when each instruction has 2
operands (one memory and one register)?
b) what is the maximum number of operands when the total number of opcodes is 9?


Question 6: (20%)
Suppose the main memory of a byte-addressable system has the size of 16KB, the size of cache is 128
blocks, and the size of each block is 32 bytes. What is the filed format of the memory reference when
a) the direct cache mapping is used?
b) the fully associative cache mapping is used?
c) 4-way set associative cache mapping is used?

Question 7 (20%): In a byte-addressable system with a virtual address space of 32K and a physical
address space of 4K,
a) what are the formats of physical and virtual addresses?
b) what is the total number of entries in the page table?
c) what is the minimum number of entries with valid bit zero in the page table?

Submission Instructions
You should submit your answers in one PDF file that contains your full name and Unikey. For
each question, you must explain your solution and show how you can get the final answer.
Only the PDF file submitted on Canvas will be accepted for marking. All other file types
(including word files) will be considered as a missed submission (mark of 0). Late submission
penalty is 5% of the max marks per calendar day and after 10 calendar days late, a mark of 0
will be awarded. Please submit your PDF file with the following name format:
LastName_FirstName_Unikey.pdf