A Level Computer Science OCR Practice Exam

Which LMC instruction would be used to load data?

1. STA

2. LDA

3. BRA

4. BRP

The correct answer is: LDA

The instruction that is used to load data in the Little Man Computer (LMC) model is LDA, which stands for "Load Accumulator." When this instruction is executed, it retrieves a value from a specified memory address and places it into the accumulator, which is a special register that holds intermediate data for operations. Loading data into the accumulator is essential for performing calculations or processing before producing any output. The other instructions serve different purposes: STA is used to store the value from the accumulator into a specified memory location, BRA is a branch instruction that allows jumping to a different part of the program without affecting the accumulator, and BRP is a conditional branch instruction that directs the flow of execution based on whether the accumulator holds a positive value. Thus, LDA is the correct choice for loading data in the LMC architecture.