// ALU inside execute wire [31:0] alu_out = (opcode == ADD) ? ID_EX_rs1 + ID_EX_rs2 : ...;
wire [3:0] wgray = wptr ^ (wptr >> 1); wire [3:0] rgray = rptr ^ (rptr >> 1); Advanced Chip Design- Practical Examples In Verilog
always_comb begin next = state; case (state) IDLE: if (cpu_req) next = TAG_CHECK; TAG_CHECK: if (hit) next = HIT_FILL; else next = MISS_REFILL; ... endcase end // Implement LRU replacement, write-back vs write-through endmodule | Tool | Purpose | |------|---------| | Verilator | Fast simulation + linting | | Yosys | Synthesis to generic netlist | | OpenSTA | Static timing analysis | | GTKWave | Waveform viewing | | SymbiYosys | Formal verification (SVA) | // ALU inside execute wire [31:0] alu_out = (opcode == ADD)
// Stage 1: Instruction Fetch always @(posedge clk or negedge rst_n) begin if (!rst_n) begin pc <= 32'b0; IF_ID_instr <= 32'b0; end else begin pc <= pc_next; IF_ID_instr <= instr_mem_data; IF_ID_pc <= pc; end end output reg sig_dst )
always @(posedge clk_dst or negedge rst_n) begin if (!rst_n) sync, meta <= 2'b00; else sync, meta <= meta, sig_src; end
always @(posedge gated_clk) q <= d; endmodule
Add write buffer, ECC, and bank interleaving. 4. Clock Domain Crossing (CDC) Example: 2-flop synchronizer (single-bit) module sync_single ( input clk_dst, rst_n, input sig_src, output reg sig_dst ); reg meta, sync;