factor_rom_i.v

基于VHDL语言的一个FFT快速傅里叶变换程序采用4蝶形算法

module	factor_rom_I
(
	clk,
	addr,
	data
);

input				clk;
input		[5:0]	addr;
output		[15:0]	data;

reg			[15:0]	data;


function	[15:0]	romout;
	input	[5:0]	addr;
// 1位整数,14位小数
	case (addr)
		 0 : romout = 16'h4000;
		 1 : romout = 16'h3FFB;
		 2 : romout = 16'h3FEC;
		 3 : romout = 16'h3FD3;
		 4 : romout = 16'h3FB1;
		 5 : romout = 16'h3F84;
		 6 : romout = 16'h3F4E;
		 7 : romout = 16'h3F0E;
		 8 : romout = 16'h3EC5;
		 9 : romout = 16'h3E71;
		10 : romout = 16'h3E14;
		11 : romout = 16'h3DAE;
		12 : romout = 16'h3D3E;
		13 : romout = 16'h3CC5;
		14 : romout = 16'h3C42;
		15 : romout = 16'h3BB6;
		16 : romout = 16'h3B20;
		17 : romout = 16'h3A82;
		18 : romout = 16'h39DA;
		19 : romout = 16'h392A;
		20 : romout = 16'h3871;
		21 : romout = 16'h37AF;
		22 : romout = 16'h36E5;
		23 : romout = 16'h3612;
		24 : romout = 16'h3536;
		25 : romout = 16'h3453;
		26 : romout = 16'h3367;
		27 : romout = 16'h3274;
		28 : romout = 16'h3179;
		29 : romout = 16'h3076;
		30 : romout = 16'h2F6B;
		31 : romout = 16'h2E5A;
		32 : romout = 16'h2D41;
		33 : romout = 16'h2C21;
		34 : romout = 16'h2AFA;
		35 : romout = 16'h29CD;
		36 : romout = 16'h2899;
		37 : romout = 16'h275F;
		38 : romout = 16'h261F;
		39 : romout = 16'h24DA;
		40 : romout = 16'h238E;
		41 : romout = 16'h223D;
		42 : romout = 16'h20E7;
		43 : romout = 16'h1F8B;
		44 : romout = 16'h1E2B;
		45 : romout = 16'h1CC6;
		46 : romout = 16'h1B5D;
		47 : romout = 16'h19EF;
		48 : romout = 16'h187D;
		49 : romout = 16'h1708;
		50 : romout = 16'h158F;
		51 : romout = 16'h1413;
		52 : romout = 16'h1294;
		53 : romout = 16'h1111;
		54 : romout = 16'h0F8C;
		55 : romout = 16'h0E05;
		56 : romout = 16'h0C7C;
		57 : romout = 16'h0AF1;
		58 : romout = 16'h0964;
		59 : romout = 16'h07D5;
		60 : romout = 16'h0645;
		61 : romout = 16'h04B5;
		62 : romout = 16'h0323;
		63 : romout = 16'h0192;
		default : romout = 16'hxxxx;
	endcase
endfunction

always @ (posedge clk)
begin
	data <= romout(addr);
end

//assign data = romout(addr);

endmodule