Edexcel GCSE Computer Science (1CP2) Exam Questions

• A Desktop computer (1)
• The only correct answer is A. The correct answer is Desktop computer.
• B is not correct because a microwave oven uses an embedded system, built into it, to control a dedicated function
• C is not correct because a washing machine uses an embedded system, built into it, to control a dedicated function
• D is not correct because a traffic light uses an embedded system, built into it, to control a dedicated function

Award one mark for any of the following up to a maximum of two marks:

• Program instructions are stored in main memory/RAM (1)
• The data used by the program is stored in main memory/RAM (1)
• The CPU fetches/reads instructions from main memory to execute them (1)
• The program can be run without the instructions being input again (1)

Allow 'the program is stored in memory' for one mark.

Do not accept answers about programs being stored on secondary storage, such as a hard disk or USB memory stick.

Do not accept answers that only describe the von Neumann architecture (e.g. having a CPU and memory) without stating that instructions are stored in main memory.

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

• The file's entry is removed from the folder/directory (1) so the file no longer appears in the list of files/is no longer listed (1)
• The (disk) space used by the file is marked as free/available/unused (1) so another file can be saved/stored in that space (1)
• The file's data/contents are not erased/removed (1) so the file may still be recovered until the space is overwritten (1)

A point stated without development, e.g. 'the file is removed from the folder', earns one mark only.

For the first mark, accept that the file's entry is removed from the folder/directory; the second mark must state that the file no longer appears/is listed.

Do not accept 'stays on disk' alone for the third point; accept 'data is not erased' or 'contents remain'.

Do not accept 'the file is wiped from the disk straight away' or 'the data is destroyed and can never be recovered'.

Do not accept 'the file is moved to the recycle bin/bin' or 'the file is deleted from the hard drive' on its own, as this does not describe what happens to the file or the disk space.

Do not accept responses about moving the file to another folder.

Indicative content

Machine independence

• A high-level language is machine independent, so the same source code can be run on different types of computer with few or no changes.
• The company can write the program once and sell it to users with different computers, without rewriting the code for each type of computer.
• Only one version of the program needs to be written and maintained, so development takes the company less time.

Processor specificity

• A low-level language is processor-specific, so a program written for one processor will not run on a different processor without being rewritten.
• Assembly language instructions depend on the instruction set of the particular processor, so the company would need a separate version of the program for each type of computer.
• Writing a separate low-level version for every type of computer would take the company much longer than writing one high-level program.
• Low-level code gives direct control of the hardware of one processor, so it is better suited to device drivers than to a program that must run on many different computers.

Translation

• High-level source code is translated for each type of computer by a compiler or an interpreter, so one version of the source code is enough for all the users.
• Assembly language is translated into machine code by an assembler, and the assembler produces machine code for one specific processor only.
• Machine code is already in a form that one particular processor can execute directly, but the same machine code will not run on a different processor.
• Each high-level statement translates into several machine code instructions, so the programmer does not need to know the instruction set of the processor.

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 both high-level machine independence and low-level processor specificity, with the effect on the company's decision.
• Do not award low-level language, assembly language or machine code as portable, or 'high-level languages are written in English/like English' as a reason for machine independence.