8-bit Processor Design
A Logisim processor developed from an 8-bit ALU through to a register file, memory system, control unit, and single-cycle CPU.
Digital Logic DesignLogisim
Built across three stages in Logisim, each building on the last.
8-bit ALU
Core combinational building blocks: a 2’s-complement converter, rotate-left and rotate-right circuits, an 8-bit full adder, and a custom equality comparator, combined into an ALU supporting add, or, and, and rotate operations with zero, sign, carry, overflow, and equality flags.
Memory and register file
An eight-register file, ROM-based instruction memory, RAM-based data memory, a control unit, and a 21-bit instruction format supporting arithmetic, logical, load/store, and immediate operations.
Single-cycle processor
Extends the CPU with branching, jumps, jump-and-link, jump-register, and set-less-than operations, adding an expanded ALU, a new control unit, and additional multiplexers for program-counter and destination-register selection.