Edexcel GCSE Computer Science (1CP2) Exam Questions

• A Decodes instructions (1)
• The only correct answer is A. The correct answer is Decodes instructions.
• B is not correct because the arithmetic logic unit performs arithmetic operations
• C is not correct because main memory stores data and instructions
• D is not correct because registers temporarily store data being processed

• C 128 (1)
• The only correct answer is C. The correct answer is 128.
• A is not correct because 6 bits give only 64 different combinations
• B is not correct because 127 is the largest 7-bit value, not the number of characters that 7 bits can represent
• D is not correct because 256 characters need 8 bits, as used by 8-bit extended ASCII

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

• Data/packets are delivered to the correct device (1) because the IP address identifies that device on the internet (1)
• A reply is sent back to the device that made a request (1) because the sender's IP address is used as the destination address for the reply (1)
• Routers can forward packets to the right device (1) because each packet's destination IP address matches only one device (1)
• A device can be contacted by other devices (1) because other devices use its IP address to send data to it (1)

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

Allow 'so the router knows where to send data' only when expanded to say the IP address identifies the destination device / is used by routers to forward the packet to that device.

Do not accept 'so it can connect to the internet' / 'so it can access the internet' without saying how the address is used to identify the device or deliver data to it.

Do not accept 'so the device can be identified' on its own without saying what the identification is used for, e.g. delivering data or returning a reply.

Do not award a mark for restating that an IP address is unique / every device has a different address.

Indicative content

What a device driver is and how the operating system uses it

• A device driver is a program that controls a peripheral device such as a graphics tablet by communicating with the operating system.
• The driver translates instructions from the operating system into signals that the graphics tablet understands, and passes the artist's pen movements back to the operating system.
• The operating system loads the driver into memory when the tablet is connected, so that it can then send data to the tablet and receive input from it.
• Without a driver the operating system cannot control the tablet, so the tablet does not work.

Why each peripheral needs its own driver

• Every make and model of peripheral uses its own set of commands, so a driver is written for that particular device.
• The drivers already installed for the studio's older tablets do not work with the new model, even though both are graphics tablets.
• An operating system includes drivers for many common devices, but it does not have one for a brand new model.
• The correct driver means the pen movements are received by the computer in the form the drawing program expects.

What must be done before an artist can use a new tablet

• The new tablet is supplied with its driver on a disc or as a download, and it must be installed on each computer.
• The operating system may need to be updated so that it recognises the new model.
• The driver must be enabled or selected for the tablet once it is installed.
• Drivers are updated later to fix faults or to improve performance.
• If the correct driver is not installed, the tablet does not work or some of its features are not available.

Additional guidance

• Level 3 responses must explain why a driver is specific to a device and what must be done before an artist can use a new tablet, as well as describing what a driver is, all applied to the studio.
• Responses that only state what a driver is, or that state a driver must be installed without explaining why the tablet needs its own driver, are limited to Level 1.
• Accept 'software', 'program' or 'set of instructions' for a driver.
• Do not accept a device driver described only as a cable or a physical connection.
• Do not accept the claim that all drivers are already built into the operating system, or that one driver works for every graphics tablet.

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)