Edexcel GCSE Computer Science (1CP2) Exam Questions

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

• The program (and its data) is copied/loaded from secondary storage into main memory/RAM (1) so that the CPU can fetch/execute its instructions (1)
• An area of main memory is allocated/reserved for the program (1) that is large enough to hold the program and its data (1)
• The operating system checks that there is enough free main memory (1) before the program can be started/loaded, otherwise it cannot run/an error is reported (1)
• The operating system keeps a record of the memory addresses used by the program (1) so that its instructions and data can be found when it runs (1)

Allow 'loaded into RAM', 'stored in memory' and 'put into main memory' as equivalent to copied into main memory.

A single statement that the program is loaded/stored in main memory, with no linked development, can be given one mark only.

Do not accept descriptions of the CPU fetching/executing instructions that do not refer to the operating system loading or allocating memory.

Do not accept responses about virtual memory (moving processes to secondary storage) or about which process runs next on the CPU.

Do not accept the program being run from secondary storage/hard disk.

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

• The memory can be reused/allocated to another program (1) so other programs have enough main memory to run (1)
• Freeing the memory stops main memory becoming full (1) so the computer can load/run new programs (1)
• The closed program's data is no longer needed (1) so keeping it would waste main memory (1)
• The operating system can give the freed memory to a program that needs more (1) so that program can continue to run (1)

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

Do not accept 'to make the computer faster' on its own without saying how freeing memory helps.

Do not accept 'to delete the program' or 'to save the program' because closing a program does not remove it from secondary storage.

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

• The operating system uses the printer's device driver to communicate with the printer (1) so the print job is sent as commands the printer can carry out (1)
• The operating system holds print jobs in a queue/buffer (1) because the computer sends data faster than the printer can print it (1)
• The operating system reports the printer's status to the user (1) so the user knows what to do when there is a problem such as the paper running out (1)
• The operating system handles interrupts/signals from the printer (1) so a problem such as a paper jam is dealt with while other programs carry on running (1)

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

Allow a point about the operating system loading/installing the device driver for a new printer (1) provided the second mark gives a reason that is not the same as the driver communication point, e.g. so the new printer can be used/controlled by the operating system (1)

Award 1 mark for stating that print jobs are held in a queue/a buffer; the second mark needs the linked reason that the printer prints more slowly than data is sent.

Do not accept restating the question, e.g. 'it manages the printer' or 'it controls the peripherals', without saying how or why.

Do not accept 'it lets the printer connect to the computer' or 'it stops the printer being damaged' without a linked reason.

Do not accept 'it makes the printer print faster' as the operating system cannot increase the printer's speed.