ALU Instruction

Concept

An ALU instruction is an instruction handled by the arithmetic logic unit of a processor. In a simplified Game Boy processor model, ALU instructions are decoded and executed by the executeALUInstruction task on the modeled register file (A, F, B, C, D, E, H, L), with concrete instructions such as ADD H (8'h84) and ADC H (8'h8C) performing arithmetic on register operands and updating the Zero, Subtract, Half-Carry and Carry flags in register F. In a different sense, ALU instruction also refers to a member of an ALU instruction set, such as the 14 arithmetic and logical instructions implemented by an 8-bit ERSFQ wave-pipelined ALU fabricated at MIT Lincoln Lab's 10 kA/cm2 SFQ5ee process.

First seen 6/20/2026

Last seen 6/20/2026

Evidence 2 chunks

Wiki v1

WIKI

ALU Instruction

An ALU instruction is, at the processor level, an instruction decoded and executed by the arithmetic logic unit (ALU) of a CPU. In the context of a simplified Game Boy–style processor model described in a digital-design and verification course, ALU instructions are dispatched to a single task, executeALUInstruction(byte instr), which is responsible for applying the corresponding arithmetic or logical operation to the modeled register file ^[1].

Role in a simplified processor model

READ FULL ARTICLE →

NEIGHBORHOOD

No graph connections found for this entity yet. It may appear in future ingestion runs.

explore full graph →

RELATIONSHIPS

3 connections

ADC Instruction ← part of 95% 2e

The ADC instruction is one specific ALU instruction executed by the model.

executeALUInstruction ← implements 98% 1e

The executeALUInstruction task executes ALU instructions on the model's internal registers.

ADD Instruction ← part of 95% 1e

The ADD instruction is one specific ALU instruction to be implemented in the model.

LINKED ENTITIES

3 links

executeALUInstruction IMPLEMENTS Extracted graph relationship

ADC Instruction PART_OF Extracted graph relationship

ADD Instruction PART_OF Extracted graph relationship

CITATIONS

4 sources

4 citations — click to collapse

[1] executeALUInstruction is a task (not a function) inside the gameboyprocessor class that applies an ALU instruction byte to the modeled registers A, F, B, C, D, E, H, L. Golden reference (course_cdandverif, KU Leuven Diepenbeek)

[2] The ADC H instruction (opcode 8'h8C) computes A = A + H + Cin, with the worked example A = 0 + 5 + 0 = 5. Golden reference (course_cdandverif, KU Leuven Diepenbeek)

[3] An ADD-style ALU instruction stores A = A + H, clears F(2), sets F(3) only when the result is 0x00, sets F(1) only on a half-carry from lower to higher nibble, and sets F(0) only on an 8-bit overflow. Golden reference (course_cdandverif, KU Leuven Diepenbeek)

[4] A wave-pipelined 8-bit ERSFQ parallel ALU was designed with a 14-instruction arithmetic/logical instruction set, fabricated in MIT Lincoln Lab SFQ5ee 10-kA/cm2 process with 6840 Josephson junctions, and tested for all instructions up to 2.8 GHz. ERSFQ 8-bit Parallel Arithmetic Logic Unit