8bit Multiplier Verilog Code Github [ESSENTIAL]
This code uses the built-in multiplication operator * to perform the multiplication. The second example uses a loop to perform the multiplication.
# 8-bit Multiplier in Verilog
Many University courses host their lab materials on GitHub, providing clean, well-commented code for 8-bit multipliers. 6. Tips for Implementation
// Stage 6: Add with seventh partial product ripple_carry_adder #(.WIDTH(13)) adder06 ( .a(carry[4][0], sum[4][7:0]), .b(pp[6] << 6), .cin(1'b0), .sum(sum[5][7:0], product[11:8]), .cout(carry[5][0]) ); 8bit multiplier verilog code github
Booth's algorithm reduces the number of partial products by encoding signed multipliers. radix-4 Booth multipliers cut the number of partial products in half (from 8 to 4 for an 8-bit multiplier), significantly speeding up addition stages at the cost of more complex control logic. Wallace Tree Multiplier
// File: multiplier_8bit_structural.v module multiplier_8bit_structural ( input wire [7:0] A, input wire [7:0] B, output wire [15:0] P ); wire [7:0] p_prod [7:0]; // Matrix to hold 64 partial products // Generate partial products genvar i, j; generate for (i = 0; i < 8; i = i + 1) begin : gen_p_prod_row for (j = 0; j < 8; j = j + 1) begin : gen_p_prod_col assign p_prod[i][j] = A[j] & B[i]; end end endgenerate // Internal wires for adder tree connections wire [7:0] sum [6:0]; wire [7:0] carry [6:0]; // Row 0 Initialization assign P[0] = p_prod[0][0]; // Manual/Loop assignment of the adder array for reduction // (For a highly optimized structural repository, explicitly instantiate // full_adder and half_adder modules here to demonstrate gate-level routing) // Simple dataflow equivalent of the structural addition chain: assign carry[0], sum[0] = p_prod[0][7:1] + p_prod[1][6:0]; assign P[1] = sum[0][0]; assign carry[1], sum[1] = carry[0], p_prod[1][7] + sum[0][7:1] + p_prod[2][6:0]; assign P[2] = sum[1][0]; assign carry[2], sum[2] = carry[1], p_prod[2][7] + sum[1][7:1] + p_prod[3][6:0]; assign P[3] = sum[2][0]; assign carry[3], sum[3] = carry[2], p_prod[3][7] + sum[2][7:1] + p_prod[4][6:0]; assign P[4] = sum[3][0]; assign carry[4], sum[4] = carry[3], p_prod[4][7] + sum[3][7:1] + p_prod[5][6:0]; assign P[5] = sum[4][0]; assign carry[5], sum[5] = carry[4], p_prod[5][7] + sum[4][7:1] + p_prod[6][6:0]; assign P[6] = sum[5][0]; assign carry[6], sum[6] = carry[5], p_prod[6][7] + sum[5][7:1] + p_prod[7][6:0]; assign P[7] = sum[6][0]; // Final upper bits computation assign P[15:8] = carry[6], p_prod[7][7] + sum[6][7:1]; endmodule Use code with caution. 3. Writing the Testbench (Simulation File)
This design explicitly defines the gate-level combinational logic, making it architecture-independent and highly educational. This code uses the built-in multiplication operator *
// Shift right multiplier, shift left multiplicand multiplier <= multiplier >> 1; multiplicand <= multiplicand << 1; counter <= counter + 1;
# Vivado, ModelSim, and Quartus junk files *.log *.jou *.vcd *.wdb xsim.dir/ work/ transcript vsim.wlf Use code with caution. 5. Writing a Professional GitHub README.md
module booth_multiplier_8bit ( input signed [7:0] a, b, // signed 8-bit inputs output signed [15:0] product ); reg signed [15:0] pp [0:3]; integer i; always @(*) begin // Radix-4 Booth encoding of B // Simplified example: actual impl requires recoding logic for (i = 0; i < 4; i = i + 1) begin case (b[2*i+1], b[2*i], b[2*i-1]) // ... booth encoding cases default: pp[i] = 16'sb0; endcase end product = pp[0] + pp[1] + pp[2] + pp[3]; end reg signed [15:0] pp [0:3]
If your hardware system uses multiplication at different times, use a single multiplier multiplexed across multiple data paths to reduce the circuit size on your chip.
module ripple_carry_adder #( parameter WIDTH = 8 )( input wire [WIDTH-1:0] a, input wire [WIDTH-1:0] b, input wire cin, output wire [WIDTH-1:0] sum, output wire cout );
module tb_eight_bit_multiplier();