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 endmodule
module array_multiplier_8bit ( input [7:0] A, B, output [15:0] P ); wire [7:0] pp0, pp1, pp2, pp3, pp4, pp5, pp6, pp7; wire [15:0] sum_stage0, sum_stage1, sum_stage2, sum_stage3; // Generate partial products (AND gates) assign pp0 = 8A[0] & B; assign pp1 = 8A[1] & B; assign pp2 = 8A[2] & B; assign pp3 = 8A[3] & B; assign pp4 = 8A[4] & B; assign pp5 = 8A[5] & B; assign pp6 = 8A[6] & B; assign pp7 = 8A[7] & B;
Run with:
module sequential_multiplier_8bit ( input clk, rst, start, input [7:0] a, b, output reg [15:0] product, output reg done ); reg [2:0] count; reg [7:0] multiplicand, multiplier; reg [15:0] acc; always @(posedge clk or posedge rst) begin if (rst) begin count <= 0; done <= 0; product <= 0; acc <= 0; end else if (start) begin count <= 0; multiplicand <= a; multiplier <= b; acc <= 0; done <= 0; end else if (!done && count < 8) begin if (multiplier[0]) acc <= acc + 8'b0, multiplicand; multiplicand <= multiplicand << 1; multiplier <= multiplier >> 1; count <= count + 1; end else if (count == 8 && !done) begin product <= acc; done <= 1; end end endmodule
: Educational FPGAs (like BASYS 3 or DE10-Lite), resource-constrained designs without DSP slices. Verilog Implementation #3: Sequential (Pipelined) Multiplier Best for low-area designs where speed is not critical. The multiplication takes 8 clock cycles.
module wallace_tree_8bit ( input [7:0] A, B, output [15:0] P ); // Step 1: generate partial products wire [7:0] pp[0:7]; genvar i, j; generate for(i = 0; i < 8; i = i+1) begin assign pp[i] = 8A[i] & B; end endgenerate // Step 2: reduction using full/half adders (not shown in full) // The tree would reduce 8 vectors to 2 vectors (sum and carry) wire [15:0] sum_vec, carry_vec;
: A full gate-level array multiplier would require a ripple or carry-save adder tree. For clarity, the above is simplified. Real implementations use half-adders and full-adders in a structured array.
// Adder tree (simplified example – real design uses full adders) assign sum_stage0 = 8'b0, pp0 + 7'b0, pp1, 1'b0; assign sum_stage1 = sum_stage0 + 6'b0, pp2, 2'b0; // ... continue for all partial products assign P = sum_stage3; // Final result after all additions endmodule
08/29/2012 @ 3:42 pm
I’m actually looking forward to checking this one out. Serbian Film would have been better if not for all the hype surrounding the film. Salo ranks up there with this other film Sweet Movie as beautiful repulsing films I’ll never watch again.
I’m equally repulsed and intrigued by the concept of this film though.