Definitive 20-Question Sequence | Grade 9 Benchmarking
Continuous Improvement: Action Plan
Question 1
3 Marks
Define the purpose of the following registers:
Mark Keys
PC: Next address | ACC: Results of calculations | MDR: Raw data/instruction.
Question 2
2 Marks
Identify two primary functions of the Control Unit (CU) .
CU Key
1. Decodes instructions [1]. 2. Coordinates / sends timing signals to hardware [1].
Question 3
2 Marks
State the role of the ALU and identify one operation it performs.
ALU Key
Performs mathematical calculations [1] and logical comparisons (e.g. AND/OR/NOT) [1].
Question 4
2 Marks
Explain the function of Cache memory in the CPU.
Cache Key
Provides fast access to frequently used data [1], reducing the need to fetch from the slower RAM [1].
Question 5
2 Marks
Describe what happens during the Decode stage of the FDE cycle.
Cycle Key
The Control Unit (CU) [1] interprets/understands the instruction to determine what action is required [1].
Question 6
2 Marks
Contrast the MAR and MDR .
Register Key
MAR stores the address (location) [1]. MDR stores the actual data/instruction [1].
Question 7
2 Marks
Define Clock Speed and identify its unit of measurement.
Performance Key
The number of cycles per second [1]. Measured in Hertz (Hz) [1].
Question 8
2 Marks
Explain why having more Cores can improve performance.
Performance Key
Allows multiple instructions to be processed simultaneously / at the same time [1] across independent processors [1].
Question 9
2 Marks
How does increasing Cache Size affect CPU performance?
Performance Key
More frequently used data can be stored for fast access [1], reducing time wasted fetching from RAM [1].
Question 10
2 Marks
State what happens to the Program Counter (PC) at the start of every Fetch cycle.
Cycle Key
It is incremented (increased by 1) [1] to point to the address of the next instruction [1].
Question 11
2 Marks
Define an Embedded System .
Embedded Key
A computer system with a single, dedicated function [1] built within a larger device [1].
Question 12
2 Marks
Identify two benefits of using Embedded Systems over general-purpose computers.
Embedded Key
Cheaper to produce, more reliable, power efficient, and compact size.
Question 13
2 Marks
AO3 Evaluation: Explain why doubling the number of cores does not always double the CPU speed.
Performance Evaluated
Software/Algorithm may not be written to use multiple cores [1]. Some tasks are sequential and must wait [1].
Question 15
2 Marks
Describe the relationship between RAM and the MAR during a Fetch.
Logic Key
The address in the MAR is sent to RAM [1] to locate/select the specific cell to be fetched [1].
Question 16
1 Mark
Identify which component of the CPU carries out mathematical and logical comparisons.
Solution
ALU (Arithmetic Logic Unit).
Question 17
1 Mark
Identify the component that sends signals to the rest of the CPU to coordinate the cycle.
Solution
Control Unit (CU).
Question 18
2 Marks
State one advantage of Level 1 Cache over Level 3 Cache .
Cache Evaluated
Level 1 is significantly faster and has lower latency as it is closer/integrated into the core [1].
Question 19
2 Marks
Identify two examples of embedded systems found in a modern home.
Examples
Microwave, Washing machine, Dishwasher, Smart thermostat.
Question 20
2 Marks
Final AO3 Assessment: A student replaces a 3.0GHz processor with a 2.5GHz quad-core processor. Explain if this is definitely an upgrade.
Evaluation
Not necessarily [1]. While it has more cores for multitasking, the clock speed per core is slower [1], which may hinder single-threaded apps.
Question 21
3 Marks
[AO2 Application] Component Scenario Match: Match the CPU component to the specific software event it handles.
Examiner Key
ALU (Logic calculation) | CU (Coordination) | Cache (High-speed storage of data).
Question 22
2 Marks
[Danger Zone] CPU Access: Explain why the CPU does not fetch instructions directly from the Secondary Storage (HDD/SSD) during the FDE cycle.
Examiner Key
Secondary storage is significantly too slow for the CPU's processing speed [1]. Instructions must first be loaded into RAM (Main Memory) for the CPU to fetch them [1].
Generate 1.1 Action Plan