Sound.v

`timescale 1ns / 1ps

module music(
	input clk,
	input music_sel,
	output reg speaker
);



reg[1:0] c;

always @(posedge clk) c=c+1;

reg [30:0] tone;
always @(posedge c[1]) tone <= tone+31'd1;

wire [7:0] fullnote;
music_ROM get_fullnote(.clk(clk), .address(tone[27:22]), .note(fullnote), .music_sel(music_sel));

wire [2:0] octave;
wire [3:0] note;
divide_by12 get_octave_and_note(.numer(fullnote[5:0]), .quotient(octave), .remain(note));

reg [8:0] clkdivider;
always @*
case(note)
	 0: clkdivider = 9'd511;//A
	 1: clkdivider = 9'd482;// A#/Bb
	 2: clkdivider = 9'd455;//B
	 3: clkdivider = 9'd430;//C
	 4: clkdivider = 9'd405;// C#/Db
	 5: clkdivider = 9'd383;//D
	 6: clkdivider = 9'd361;// D#/Eb
	 7: clkdivider = 9'd341;//E
	 8: clkdivider = 9'd322;//F
	 9: clkdivider = 9'd303;// F#/Gb
	10: clkdivider = 9'd286;//G
	11: clkdivider = 9'd270;// G#/Ab
	default: clkdivider = 9'd0;
endcase

reg [8:0] counter_note;
reg [7:0] counter_octave;
always @(posedge clk) counter_note <= counter_note==0 ? clkdivider : counter_note-9'd1;
always @(posedge clk) if(counter_note==0) counter_octave <= counter_octave==0 ? 8'd255 >> octave : counter_octave-8'd1;
always @(posedge clk) if(counter_note==0 && counter_octave==0 && fullnote!=0 && tone[21:18]!=0) speaker <= ~speaker;
endmodule