Learning objective
Machine-code/assembly language operations: Understand and apply the basic machine-code operations of: • load • add • subtract • store • branching (conditional and unconditional) • compare • logical bitwise operators (AND, OR, NOT, XOR) • logical • shift right • shift left • halt. Use the basic machine-code operations above when machine-code instructions are expressed in mnemonic form- assembly language, using immediate and direct addressing.
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Structure and role of the processor and its components
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Machine-code/assembly language operations
Aqa A Level Computer ScienceFundamentals of computer organisation and
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Quick explanation
Machine-code/assembly language operations: Understand and apply the basic machine-code operations of: • load • add • subtract • store • branching (conditional and unconditional) • compare • logical bitwise operators (AND, OR, NOT, XOR) • logical • shift right • shift left • halt. Use the basic machine-code operations above when machine-code instructions are expressed in mnemonic form- assembly language, using immediate and direct addressing
- This point belongs to Structure and role of the processor and its components, especially Machine-code/assembly language operations.
- You need to be able to machine-code/assembly language operations: Understand and apply the basic machine-code operations of: • load • add • subtract • store • branching (conditional and unconditional) • compare • logical bitwise operators (AND, OR, NOT, XOR) • logical • shift right • shift left • halt. Use the basic machine-code operations above when machine-code instructions are expressed in mnemonic form- assembly language, using immediate and direct addressing.
- Use the linked flashcards and practice questions to check recall, then practise applying the idea in an exam-style answer.
Why it matters
This objective helps connect Machine-code/assembly language operations to exam-style questions, flashcards, and revision notes for Structure and role of the processor and its components.
Quick student answer
Which instruction uses immediate addressing to load the value 12 into the accumulator?
Direct answer
LOAD #12
Key terms
- Mnemonic: A human-readable abbreviation used to represent a machine-code operation in assembly language, such as LOAD, ADD or STORE.
- Direct addressing: An addressing method in which the operand identifies the memory location containing the data to be used.
Common trap
Confusing a value with a memory address: LOAD #20 uses the immediate value 20, while LOAD 20 uses direct addressing and loads the value stored at memory location 20.
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Related learning objectives
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