1.Processor Architecture
Gained a comprehensive understanding of an 8-bit processor's components, including the ALU, registers, Program Counter (PC), Instruction Register (IR), and Control Unit.
Learned how 2-address format instructions operate, such as ADD R1, R2, which adds R2 to R1 and stores the result in R1.
2.Register Addressing Mode
Explored the use of registers for faster data access compared to memory.
Implemented operations like ADD, SUB, AND, and OR, emphasizing the role of the register file for intermediate data storage.
3.Control Unit Design
Designed a control unit to decode instructions and generate control signals using state diagrams for step-by-step execution.
Coordinated synchronization across processor components to ensure seamless operation.
4.ALU Operations
Designed the ALU for efficient arithmetic and logical operations, including edge case handling for carry, overflow, and zero flags.
Ensured the ALU responded accurately to control signals.
5.Instruction Set Architecture (ISA)
Defined a custom ISA with arithmetic, logic, and data movement instructions, optimized for the 2-address format and register addressing mode.
6.Memory and I/O
Learned the interaction between memory and the processor using components like the Memory Address Register (MAR) and Read-Only Memory (ROM).
Focused on memory management and I/O considerations for a complete processor design.
7.Simulation in Logisim
Designed and simulated the processor using Logisim, testing key components like the ALU, registers, and control unit.
Verified functionality for various instructions under different scenarios.
1.Instruction Decoding
Challenge: Ensuring accurate decoding and proper operand handling.
Solution: Used structured state diagrams to design a reliable control unit with precise signal generation.
2.Register File Design
Challenge: Supporting simultaneous read and write operations without errors.
Solution: Tested each operation incrementally and synchronized with the control unit.
3.ALU Operations
Challenge: Handling multiple operations and managing edge cases like carry and overflow.
Solution: Modularized ALU design into arithmetic and logical units, testing each thoroughly.
4.Program Counter (PC) Design
Challenge: Accommodating jump and branch instructions.
Solution: Started with simple increment logic, adding branching functionality incrementally.
5.Synchronization
Challenge: Aligning all components with clock cycles to avoid data corruption.
Solution: Modular testing ensured synchronization before full system integration.
6.Component Integration
Challenge: Ensuring seamless operation when combining all components.
Solution: Integrated and tested components step-by-step, resolving issues using simulations.
7.Memory Management
Challenge: Efficient instruction fetching and temporary data handling.
Solution: Simulated memory modules like MAR and ROM, verifying interactions with other components.
Conclusion
This project offered a deep understanding of 8-bit processor design using the 2-address format and register addressing mode. Challenges such as instruction decoding, ALU operations, and component synchronization underscored the importance of modular design, iterative testing, and systematic integration. The experience enhanced our knowledge of processor architecture and hardware design, providing a solid foundation for future work in embedded systems and computer architecture.