Q1 ISA and Circuitverse practice

Implement (on circuitverse.org) a CPU supporting a tiny ISA (see below) including:

• 4 registers (R0 - R3), each is 32-bit in width
• 5 instructions {init, addi, sltR0, bezR0, halt}

Here is a python simulator for this subset of instructions: https://replit.com/@raowenjing/myTinyISA-sim#main.py

Main components of your system:  

• Instruction memory: a ROM module with 16 bytes
• PC logic (automatically +1, unless modified by bezR0)
• ALU: supporting {add, slt} operations.
• Register File: containing R0 - R3 with 2 read ports and 1 write port.
• Control Unit: able of generating corresponding MUX selection signals based on instruction opcode.

Top-level System IO:

• System input: 1-bit input serving as clock signal.
• A reset signal to clear PC = 0.
• System output: various displays (can include hex LEDs) for the content of PC and each register.

Instruction list :

Example program:

Initialize a ROM module with the above example code, such that after 15 cycles we'll see (R0 - R4) = (1, 4, 6, 0)