Edexcel GCSE Computer Science (1CP2) Exam Questions

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

• The interpreter executes each line as soon as it has been translated (1) so translation and execution happen together/at the same time (1)
• The compiler translates the whole program first (1) and the machine code is run later/separately (1)
• The interpreter translates the code and runs it while the program is running (1) whereas the compiler does not run the code it produces (1)
• The compiler produces translated code that is executed only after all the translation has finished (1) but the interpreter executes each line immediately (1)

Allow 'translates one line at a time' where it is linked to executing each line immediately.

Do not accept answers that only state that a compiler is faster/an interpreter is slower, without reference to when execution happens.

Do not accept answers that only give object code, error reporting or portability, without reference to when execution happens.

Do not accept the compiler executing the program as it translates it.

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

• The programmer can control/manipulate the hardware directly (1) because low-level instructions can access registers/memory addresses/hardware features (1)
• The code can be made to work efficiently with a specific device (1) because low-level languages are processor/chipset specific, so the instructions match that hardware (1)
• The code produced is fast to execute (1) because it is optimised for the specific processor/uses few instructions (1)
• The code produced is small (1) so it fits in the limited memory/ROM available in the device (1)

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

Fast execution and small code size are typical advantages of low-level languages; award them only where the linked reason relates to the device.

Do not accept 'it is easier to write/learn/understand' or 'it is faster to write' as a point or as the expansion, because low-level languages are not easier for these.

Do not accept 'it is close to the hardware' or 'it works with hardware' without expansion of what that allows the program to do.

Do not accept 'because it is low-level' as the expansion; the answer must say what the language/hardware allows.

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

• The same source code can be used on different processors (1) because a compiler/interpreter for each processor translates it into that processor's machine code/instructions (1)
• The program is machine/processor independent (1) because the code is translated into the machine code/instructions of each processor it is run on (1)
• A different compiler/interpreter is used for each type of processor (1) so the same source code can be translated into each processor's machine code/instructions (1)
• The program can be moved/copied to a computer with a different processor (1) because a compiler/interpreter that produces code for that processor exists (1)

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

Do not accept 'it is portable' without a linked reason about translation for different processors.

Do not accept 'it is easier to use/read/write' on its own without a linked reason about translation/processors.

Do not accept 'it is not written in binary'/'it is not machine code'/'it is not written in assembly language' as the reason without saying that the code is translated into each processor's machine code/instructions.

Do not accept the misconception that the program runs directly on any processor without being translated.