9-10乐曲演奏电路

1、9.10 乐曲演奏电路,音调控制,低音6 6MHz / 2 / 440Hz = 6818 9365 + 6818 = 16383,音长控制,全音符 1秒 四分音符 4Hz 八分音符 8Hz,9.22梁祝乐曲演奏电路 /* clk50m 输入时钟，50MHz speaker 驱动扬声器的方波 high, med, low 显示高，中，低音 */,module song(clk50m, speaker, high, med, low); input clk50m; output reg speaker; output reg3:0 high, med, low;,reg clk_6mhz; /产生

2、音阶的基准时钟 reg clk_4hz; /控制音长的时钟 reg13:0 divider, origin; /分频计数, 预置数 wire carry; /分频进位 reg7:0 counter; /节拍计数 reg2:0 count8; /分频计数 reg19:0 count20; /分频计数,/分频得到6MHz时钟 always (posedge clk50m) if(count8=7) begin count8=0; clk_6mhz=1; end else begin count8=count8+1; clk_6mhz=0; end,/分频得到4Hz时钟 always (posedg

3、e clk_6mhz) if(count20=781250) begin clk_4hz= clk_4hz; count20=0; end else begin count20=count20+1; end,/通过置数，改变分频比 always (posedge clk_6mhz) if(divider=16383) begin carry=1; divider=origin; end else begin divider=divider+1; carry=0; end,/得到驱动扬声器的方波 always ( posedge carry ) speaker = speaker;,always

4、 ( posedge clk_4hz ) /预置分频比 case( high, med, low ) h001: origin = 4915; /低音1 h002: origin = 6168; /低音2 h700: origin = 14864; /高音7 h000: origin = 16383; /休止符 endcase end,/ 分频比预置 h003:origin = 7281; / 低音3 h004:origin = 7792; / 低音4 h005:origin = 8730; / 低音5 h006:origin = 9365; / 低音6 h007:origin = 10310

5、; / 低音7 h010:origin = 10647; / 中音1 h020:origin = 11272; / 中音2 h030:origin = 11831; / 中音3 h040:origin = 12094; / 中音4 h050:origin = 12556; / 中音5 h060:origin = 12974; / 中音6 h070:origin = 13346; / 中音7 h100:origin = 13516; / 高音1 h200:origin = 13829; /高音2 h300:origin = 14109; /高音3,/演奏乐谱 always (posedge clk_4hz) begin if(counter=134) counter=0; /循环演奏 else counter=counter+1;,case(counter) 0: high, med, low = h003; /低3 1: high, med, low = h003; /持续4拍 2: high, med, low = h003; 3: high, med, low =