O-LevelComputer ScienceProgramming2210/12 · May/June 2025 · Q322 Marks

A programmer writes a program to store and sort all the data for the books in her home library.

(a)The programmer uses a high-level language to write the program. One reason for writing the program using a high-level language is that it is easier to read and write. Give two other reasons why the programmer chose to use a high-level language. 1 2[2]
(b)(i)The programmer uses an integrated development environment (IDE) to write the program. One function of the IDE is to provide a translator. Complete the statements about translators. Use the terms from the list. Some of the terms will not be used. You should only use a term once. all together all assembler binary error executable file executing interrupt line by line partial code some translating whole code A compiler translates the at once before it. A compiler produces an error report that displays errors. An interpreter translates and executes the code An interpreter stops execution when an is found and continues once it is corrected.[5]
(b)(ii)Give two other functions commonly found in an IDE. State the role of each function. Function 1 Role Function 2 Role[4]
(c)(i)The programmer wants to print a list of all her books on paper. Identify a suitable type of printer that she could use to print this list.[1]
(c)(ii)The programmer needs to connect the printer to her computer. The printer is on the same desk as her computer. Give a suitable method of data transmission that could be used to connect the computer to the printer. Explain your choice. Data transmission method Explanation[6]
(c)(iii)An even parity check is used to detect errors in the data after it has been transmitted to the printer. Describe how an even parity check detects an error.[4]

Mark scheme

Marking points from the official mark scheme (May/June 2025). The mark or mark type is shown in brackets.

[2] Any two from: • It is easier to debug. • Less likely to make errors. • The program is machine independent/portable
[5] One mark for each correct term in the correct place. A compiler translates the whole code at once before executing it. A compiler produces an error report that displays all errors. An interpreter translates and executes the code line by line. An interpreter stops execution when an error is found and continues once it is corrected.
[4] One mark for each correct function. One mark for each correct matching role description. Examples: • Code editor • Allows the programmer to write/change the program. • Run-time environment • Allows the user to run the code and see the output. • Error diagnostics • Features that can be used to find errors in the code • Auto-completion • A programmer starts to type a command word, and the IDE suggests option for completing it. • Auto-correction • If a programmer misspells a command word it is changed to the correct spelling • Prettyprint The command words/identifiers are given different colours
[1] Any one from: • Inkjet • Laser
[6] One mark from: Serial • Parallel One mark from: • Half-duplex • Full-duplex • Simplex Any four from (for descriptions matching transmission types given): serial • Serial would send bits in order // serial uses only one wire. • so won't be skewed // less likely to have errors • Serial transmission speed would be adequate. parallel • Parallel would transmit data faster. • as multiple bits are sent at the same time // ... as multiple wires are used. • For parallel, chance of skewing/errors would be low as short distance transmission only required. half/full duplex • To allow data to be sent in both directions • so any interrupts/notifications for errors can be sent back to the computer. simplex • Data only needs to be sent one direction // Data transmission doesn't need to be two-way. • as the printer may not need to send errors back to the computer
[4] • A parity bit is added to each byte. • ... to make the number of 1s/0s even // that will be 1 if the number of 1s/0s is odd // that will be 0 if the number of 1s/0s is even. • The number of 1s/0s in each byte is counted after transmission. • If any bytes have an odd number of 1s/0s an error is detected