Edexcel GCSE Computer Science (1CP2) Exam Questions

Award up to two marks for a linked description such as:

• Stores programs (including the operating system) and data that are not currently in use (1) so that they can be loaded into RAM/main memory when needed (1)
• Keeps files/programs/data when the power is turned off (1) which happens because it is non-volatile (1)
• Stores files/data for backup or archiving (1) so that they can be recovered if the originals are lost/corrupted (1)

A correct role on its own earns one mark; the second mark requires a linked development.

Accept either order if both the role and the link are given.

Do not accept 'it is non-volatile' on its own, unless it is linked to keeping data when the power is turned off.

Do not accept answers that only name a storage type (magnetic, optical, solid state) without describing a role.

Do not accept responses that describe primary storage/RAM, e.g. storing the data/instructions the CPU is currently working on, or that secondary storage makes the computer run faster.

Award up to two marks for a linked explanation such as:

• The pits and lands on a Blu-ray disc are smaller/closer together (1) because the blue laser has a shorter wavelength than the infrared laser used by a CD (1)
• More pits and lands can be stored in the same length of track (1) because the blue laser has a shorter wavelength, so it can focus on a smaller area/read smaller details (1)
• A blue laser can focus on a smaller area (1) so smaller pits and lands can be used, allowing more data to be stored on the disc (1)

For both marks, the expansion must follow/associate with the statement.

Do not accept 'a Blu-ray is newer/better' or 'a Blu-ray has more space/bigger storage' without a linked reason about the laser/pits and lands.

Do not accept answers about read/write speed, for example 'a Blu-ray spins faster', because the question asks about the amount of data stored, not how quickly it is read.

Do not award 'a Blu-ray disc can have more layers' on its own as the reason; it must be linked to the smaller pits and lands/shorter wavelength of the laser.

Do not accept 'red laser' for a CD; a CD uses an infrared laser (red is used by DVD).

Indicative content

What an embedded system is

• An embedded system is a computer system that forms part of a larger device, such as the fitness tracker.
• It performs a single, dedicated or specific task rather than being a general purpose computer.
• It is often built around a microcontroller, which contains the processor, RAM and ROM on a single chip.
• Its software is held in ROM so the tracker can run its program as soon as it is switched on.

Functions in the tracker

• Monitoring the heart rate using a sensor and processing the readings so that they can be displayed on the screen.
• Counting steps using an accelerometer and using the count to calculate the distance walked or the calories burned.
• Tracking sleep by monitoring the wearer's movement during the night.
• Controlling the touch screen so that the user can move between displays.
• Managing the battery, for example stopping the charging when the battery is full and saving power when the tracker is idle.
• Sending the collected data to a smartphone using Bluetooth so that it can be viewed in an app. Accept any other specific function of the fitness tracker that an embedded system could control.

Why an embedded system is suitable for this device

• It has low power consumption, so the battery lasts longer between charges, which matters for a device that is worn all day.
• It is small and light, so it can be fitted into a wristband.
• Its dedicated function means it does not need a full operating system, so it is reliable and does not need restarting.
• The program is small and stored in ROM, so the tracker needs only a small amount of memory.
• It can be optimised for its specific tasks, so it responds quickly to the readings from its sensors.
• The low cost per unit keeps the tracker affordable for the customer.

Levels

• Level 0 (0 marks): No rewardable content.
• Level 1 (1–2 marks): Basic, independent points are made, showing elements of understanding of key concepts/principles of computer science. (AO1) The discussion will contain basic information with little linkage between points made or application to the context. (AO2)
• Level 2 (3–4 marks): Demonstrates adequate understanding of key concepts/principles of computer science. (AO1) The discussion shows some linkages and lines of reasoning with some structure and application to the context. (AO2)
• Level 3 (5–6 marks): Demonstrates comprehensive understanding of key concepts/principles of computer science to support the discussion being presented. (AO1) The discussion is well developed, with sustained lines of reasoning that are coherent and logically structured, and which clearly apply to the context. (AO2)

Additional guidance

• Level 3 responses must cover what an embedded system is, the functions it performs in the tracker and why it is suitable for the tracker.
• Do not award installing new software/apps, functions the tracker does not perform (such as playing music) or 'it is like a phone'.