module MersenneTwister_TT400(
	input clk,
	output reg [15:0] rnd);

	parameter N = 25;
	parameter M = 11;

	reg [15:0] MT [0:(N-1)];
	reg [15:0] y;
	reg [15:0] y_next;
	integer index;
	integer indexM;

	initial
	begin
		index <= 0;
		indexM <= 0;
		rnd <= 0;
		y <= 0;
		y_next <= 0;
		`include "./MT_TT400_initialization.v"
	end

	always @(posedge clk)
	begin
		rnd <= y_next;
		
		y = MT[index];
		y = y ^ ((y << 2) & 16'h6A68);
		y = y ^ ((y << 7) & 16'h7500);
			
//		$display("%d",y);	
		y_next <= y;

		if (index + M >= N) indexM = index + M - N;
		else	indexM = index + M;

		if (MT[index][0] == 1)
		begin
			MT[index] = MT[indexM] ^ (MT[index]>>1) ^ 16'hA875;
		end
		else
		begin
			MT[index] = MT[indexM] ^ (MT[index]>>1);
		end
	
		if (index == (N-1)) index <= 0;
		else index <= index + 1'b1;
	end

endmodule