Page 65 - Computer_Science_F5

Computer Science 2. ARMv8 (AArch64): 3. x86 (Complex Instruction Set
Computing):
(a) Instruction: ldr x0, [x1]
(a) Instruction: mov eax, [ebx + 4]
(b) This instruction retrieves the
(b) Explanation: This instruction
data from the memory location
combines memory addressing
whose address is stored in x1
FOR ONLINE READING ONLY
and loads it in register x0.
from the memory location
(i) ldr: This specifies the and data. It fetches the value
operation (load). calculated by adding 4 to the

(ii) x0: This is the destination address stored in register ebx
register where the loaded and places it in register eax.
data will be stored. (i) mov: This specifies the
(iii) [x1]: This indicates the operation (move).
memory location to be (ii) eax: This is the destination
loaded. The value in register.
register x1 acts as the (iii) [ebx + 4]: This indicates
base address for memory the memory location to
access. be accessed.

Activity 1.14:

Simulation to explore how computer memory is utilised using CPU simulator
Aim:
To enhance individual knowledge and comprehension of computer memory
utilization in a practical and interactive manner

Materials:
Computer, CPU simulator software or Internet.

Instructions:
Create a program and instructions to add two numbers. The first number should
be stored in a register R00, the second number should be stored in register R01,
and the results should be stored in register R02. All instructions should appear in
the CPU instructions memory (RAM).

Step 1: Understand the components of the CPU simulator

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for Advanced Secondary Schools

Computer Science Form 5.indd 56 23/07/2024 12:32