Verilog Project: Development of an 8-Bit RISC-V Processor

R-Type Instructions:

• add: rd = rs1 + rs2 (Example: If rs1 = 5 and rs2 = 7, then rd = 12).
• sub: rd = rs1 - rs2 (Example: If rs1 = 10 and rs2 = 3, then rd = 7).
• and: rd = rs1 AND rs2 (Example: If rs1 = 1101 and rs2 = 1010, then rd = 1000).
• or: rd = rs1 OR rs2 (Example: If rs1 = 1101 and rs2 = 1010, then rd = 1111).
• xor: rd = rs1 XOR rs2 (Example: If rs1 = 1101 and rs2 = 1010, then rd = 0111).

I-Type Instructions:

• xori: rd = rs1 XOR imm (Example: If rs1 = 1101 and imm = 1010, then rd = 0111).
• ori: rd = rs1 OR imm (Example: If rs1 = 1010 and imm = 0011, then rd = 1011).
• slti: rd = (rs1 < imm) ? 1 : 0 (Example: If rs1 = 5 and imm = 8, then rd = 1).
• addi: rd = rs1 + imm (Example: If rs1 = 7 and imm = 3, then rd = 10).

Load/Store Instructions:

• lb: rd = Mem[rs1 + imm] (Example: If rs1 = 1000 and imm = 0011, then rd receives the value stored at memory position 1000 + 3).
• sb: Mem[rs1 + imm] = rs2 (Example: If rs1 = 1010, imm = 0100, and rs2 = 1101, then the value 1101 is stored at memory position 1010 + 4).

Branch Instructions:

• beq: if (rs1 == rs2) pc = pc + imm (Example: If rs1 = 6, rs2 = 6, and imm = 2, then there will be a conditional jump).
• bne: if (rs1 != rs2) pc = pc + imm (Example: If rs1 = 5, rs2 = 3, and imm = 3, then there will be a conditional jump).
• blt: if (rs1 < rs2) pc = pc + imm (Example: If rs1 = 3, rs2 = 5, and imm = 2, then there will be a conditional jump).
• bge: if (rs1 >= rs2) pc = pc + imm (Example: If rs1 = 8, rs2 = 6, and imm = 3, then there will be a conditional jump).

Jump Instructions:

• jal: rd = pc + 4; pc = pc + imm (Example: If imm = 8, then rd will receive the value of the next instruction address, and there will be an unconditional jump).
• jalr: rd = pc + 4; pc = rs1 + imm (Example: If rs1 = 12 and imm = 2, then rd will receive the value of the next instruction address, and there will be an unconditional jump to the address 12 + 2).

Shift Instructions:

• sll: rd = rs1 << rs2 (Example: If rs1 = 6 and rs2 = 2, then rd = 24).
• srl: rd = rs1 >> rs2 (Example: If rs1 = 16 and rs2 = 3, then rd = 2).
• slli: rd = rs1 << imm (Example: If rs1 = 5 and imm = 2, then rd = 20).
• srli: rd = rs1 >> imm (Example: If rs1 = 32 and imm = 3, then rd = 4).