Computer Science 0478/13 May/June 2023

Convert the binary number 10101110 to denary.

Answer explanation

To convert the binary number 10101110 to denary, we use the formula: (1*2^7) + (0*2^6) + (1*2^5) + (0*2^4) + (1*2^3) + (1*2^2) + (1*2^1) + (0*2^0) = 174

Convert the binary number 10101110 to hexadecimal.

Answer explanation

To convert binary to hexadecimal, group the binary number into sets of 4 starting from the right (1010 1110). Convert each group to its hexadecimal equivalent (A E), giving the final result AE.

Give the 8-bit binary number that would be stored after a logical left shift of three places.

Answer explanation

The 8-bit binary number after a logical left shift of three places would be '00000000' as each bit is shifted three positions to the left, filling the empty spaces with zeros.

Add the two 8-bit binary numbers 11101110 and 00110001 using binary addition. Give your answer in binary.

Answer explanation

To add 11101110 and 00110001, perform binary addition: 11101110 + 00110001 = 100111011. The answer in binary is 100111011.

Calculate the least number of bits that can be used to store the denary number 301.

Answer explanation

To store the denary number 301, we need at least 9 bits (2^8 = 256, 2^9 = 512). Therefore, the least number of bits required is 9.

Calculate the least number of bits that can be used to store the hexadecimal number A4D.

Answer explanation

To store the hexadecimal number A4D, we need 12 bits (4 bits per hexadecimal digit).

State the purpose of a core in the CPU.

Answer explanation

The purpose of a core in the CPU is to execute instructions and perform calculations, allowing the CPU to handle multiple tasks simultaneously through parallel processing.

Explain the effect of replacing the CPU with four cores on the performance of the self-checkout system.

Answer explanation

Adding four cores to the CPU can improve the performance of the self-checkout system by allowing for parallel processing of tasks, leading to faster transaction times and overall system efficiency.

Describe the role of a register in the CPU.

Answer explanation

Registers in the CPU are small, fast storage locations used to store data temporarily during processing. They hold instructions, data, and addresses for quick access by the CPU.

Identify one bus that can be found in the CPU and explain its purpose in the fetch–decode–execute cycle.

Answer explanation

The bus found in the CPU is the data bus. It carries data between the CPU, memory, and other components during the fetch–decode–execute cycle.