Edexcel GCSE Computer Science (1CP2) Exam Questions

• 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 one mark for any of the following up to a maximum of three marks:

• The address (of the next instruction) is sent from the CPU to main memory / placed on the address bus (1)
• The (next) instruction is fetched/read from main memory (RAM) (1)
• The instruction is brought/copied into the CPU / received into the MDR (1)
• The program counter (PC) is incremented/updated to hold the address of the next instruction (1)

Allow 'the PC/MAR is placed on the address bus' for the address being sent to main memory.

Allow 'the MDR receives the instruction' for the instruction being brought into the CPU.

Do not award a second mark for the instruction being fetched from main memory and the instruction being brought into the CPU; these are the same point.

Do not award 'the instruction is transferred along the data bus' on its own; this is the same point as the instruction being fetched from main memory.

Do not accept answers about decoding the instruction, e.g. 'the instruction is fetched from RAM and decoded', as decoding happens in the decode stage.

Do not accept answers about the execute stage, e.g. 'the ALU carries out the calculation' or 'the result of a calculation is stored in a register', as these happen in the execute stage.

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

• A binary digit (1)
• Has the value 0 or 1 (1)
• The smallest unit of data storage (1)
• A single 0 or 1 (1)

Allow binary digit/binary place value for binary digit

Allow a single binary digit for a single 0 or 1

Do not accept a group of 8 bits/half a nibble of 4 bits, which describe a byte or a nibble

Do not accept a binary number/binary on its own

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

• Updates/changes the location/path stored for the file (1) so the file can be found in its new folder/location (1)
• Removes the file's entry/reference from the old folder (1) so the file no longer appears/is listed there (1)
• Adds/creates an entry/reference for the file in the new folder (1) so the file appears/is listed in its new location (1)
• Updates the folder/directory listing/structure (1) to show the file's new location/path (1)

Do not accept descriptions of copying the file or leaving a duplicate in the old folder.

Do not accept deleting and recreating the file, or moving the file's data to a different physical location on the disk; the marks are for updating the folder/directory structure.