8 Bit Array Multiplier Verilog Code ›

// First row (i=0) assign s[0][0] = pp[0][0]; assign c[0][0] = 1'b0; genvar j; generate for (j = 1; j < 8; j = j + 1) begin assign s[0][j] = pp[0][j]; assign c[0][j] = 1'b0; end endgenerate

// Output assignment assign P[0] = s[0][0]; assign P[1] = s[1][0]; assign P[2] = s[2][1]; assign P[3] = s[3][2]; assign P[4] = s[4][3]; assign P[5] = s[5][4]; assign P[6] = s[6][5]; assign P[7] = s[7][6]; assign P[15:8] = s[7][7:0]; endmodule module tb_array_multiplier; reg [7:0] A, B; wire [15:0] P; array_multiplier_8bit_optimized uut (.A(A), .B(B), .P(P)); 8 bit array multiplier verilog code

// Generate partial products: pp[i][j] = A[i] & B[j] genvar i, j; generate for (i = 0; i < 8; i = i + 1) begin : pp_gen for (j = 0; j < 8; j = j + 1) begin : bit_gen assign pp[i][j] = A[i] & B[j]; end end endgenerate // First row (i=0) assign s[0][0] = pp[0][0];

[ P = \sum_i=0^7 (A \cdot B_i) \cdot 2^i ] assign c[0][0] = 1'b0

// Assign product bits assign P[1] = sum[0][0]; assign P[2] = sum[1][1]; assign P[3] = sum[2][2]; assign P[4] = sum[3][3]; assign P[5] = sum[4][4]; assign P[6] = sum[5][5]; assign P[7] = sum[6][6]; assign P[8] = final_sum[0]; assign P[9] = final_sum[1]; assign P[10] = final_sum[2]; assign P[11] = final_sum[3]; assign P[12] = final_sum[4]; assign P[13] = final_sum[5]; assign P[14] = final_sum[6]; assign P[15] = final_sum[7];

integer i, j; initial begin $monitor("Time=%0t | A=%d B=%d | Product=%d (expected %d)", $time, A, B, P, A*B); for (i = 0; i < 256; i = i + 1) begin for (j = 0; j < 256; j = j + 1) begin A = i; B = j; #10; if (P !== A*B) begin $display("ERROR: %d * %d = %d, but got %d", A, B, A*B, P); $finish; end end end $display("All tests passed."); $finish; end endmodule Running the testbench yields correct multiplication for all 65,536 input combinations. Example:

// Middle rows (i=1 to 6) genvar i; generate for (i = 1; i < 7; i = i + 1) begin // First bit of row i ha ha_i0 (.a(pp[i][0]), .b(s[i-1][0]), .sum(s[i][0]), .carry(c[i][0])); // Remaining bits for (j = 1; j < 7; j = j + 1) begin fa fa_ij (.a(pp[i][j]), .b(s[i-1][j]), .cin(c[i][j-1]), .sum(s[i][j]), .cout(c[i][j])); end // Last bit of row i assign s[i][7] = c[i][6]; end endgenerate