Page 62 - Computer_Science_F5

(ii) Store: sw (store word), sb (store memory protection.
byte) (transfer data from registers (iii) Processor control: Instructions to
to memory) change processor modes or power Chapter One: Computer architecture

(iii) Move: mov (move data between management.
registers)
FOR ONLINE READING ONLY
(iv) Input/Output (I/O): in, out (transfer (e) Special instructions
data between CPU and external Some ISAs might include specialised
devices) instructions for specific purposes, such
as:
(c) Control flow instructions (i) Floating-point operations:

These instructions control the flow of Instructions for performing
program execution by allowing for calculations on floating-point
conditional branching and jumping to numbers (numbers with decimal
different parts of the code. Examples points).
include: (ii) String manipulation: Instructions for
(i) Branch: if, else, goto (conditional working with strings of characters
execution based on register values efficiently.
or conditions) (iii) Vector processing: Instructions for

(ii) Jump: jmp (unconditional jump to performing operations on multiple
a specific instruction address) data elements simultaneously.

(iii) Call: call (call a subroutine or
function) Exercise 1.12
(iv) Return: ret (return from a subroutine 1. The passage describes two main
or function)
approaches to instruction set design:
RISC and CISC. Create a table
(d) System control instructions comparing these two approaches.
These instructions interact with the Include details like design
operating system or manage system philosophy, instruction complexity,
resources. They are typically privileged efficiency considerations, and
instructions accessible only by the
operating system or specific programs. common applications.
2. Research a specific example of a
Examples include: modern CPU (Central Processing
(i) Interrupt handling: Instructions to Unit). Identify the ISA it uses (e.g.,
handle interrupts from devices or Intel x86, ARMv8) and explain
software. why this particular ISA might be
(ii) Memory management: Instructions chosen for that specific CPU.
for managing virtual memory or

53
Student’s Book Form Five

Computer Science Form 5.indd 53 23/07/2024 12:32