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第5篇:doit_esp32_devkit_v1使用pmw呼吸灯实验

D5连接喇叭正极，GND连接喇叭负极

一、乐理准备
十二平均律（12-equal temperament）又称十二等程律。

一个八度分成12份，八个八度的十二平均音率对应的频率如下（从33Hz到7902Hz）。

相邻两个音之间的倍数是2^(1/12)，约等于1.0594630943592952645618252949463）。这样一来，高八度的do频率是低八度do的两倍。

频率与钢琴上的按键是对应的：

                                        
我们把频率440赫兹作为中央C ，C调的歌就是把频率440赫兹当作do，乐谱中写作：1=C。

相邻的两个音之间的差一个半音，12345671之间的间隔分别是“全全半全全全半”。

D调的歌就是把从440后面第二个音494赫兹当作do，乐谱中写作1=D。
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示范代码：

#include <Arduino.h>// put function declarations here://定义蜂鸣器控制管脚
#define beep_pin  5   //连无源喇叭// float k=1.0594631;
struct YINFU{       //定义音符int    freq;float  Duration;
};
//1    2   3   4  5    6         7   1   2   3     4    5    6    7
//C    D   E   F  G    A  A#     B   C1  D1, E1,   F1,  G1,  A1,  B1
//440,494,554,587,659,740,784    831,880,988,1109, 1175,1319,1480,1661struct YINFU YUEPU[128]={{831,0.55},	{740,0.15},	{622,0.55},	{740,0.15},	{988,0.3},	{831,0.15},	{740,0.15},	{831,0.8},	{0,0.55},	{0,0.3},	{622,0.3},	{740,0.3},	{831,0.3},	{740,0.3},	{622,0.3},	{494,0.15},	{440,0.15},	{740,0.15},	{622,0.15},	{554,0.4},	{0,0.3},{554,0.3},	{622,0.3},	{740,0.3},	{740,0.3},	{831,0.3},	{622,0.15},	{554,0.15},	{494,0.4},	{0,0.3},	{0,0.3},	{740,0.3},	{622,0.3},	{554,0.15},	{494,0.15},	{440,0.15},	{494,0.15},	{392,0.5},	{0,0.3},	{0,0.3},		};
//涛声依旧
struct YINFU YUEPU_TSYJ[2048]={//6               0     //6           3               5             6          5                     5     {1480,0.55},	{0,0.55},{1480,0.55},	{1109,0.55},	{1319,0.55},	{1480,0.3},	{1319,0.15},{1,0.8},{1319,0.55},   //1            2              3           3                           3  	        5                      6           5           3          2           3 {880,0.35},  {988,0.35},	{1109,0.55},{0,0.3},{1109,0.55},{0,0.15},{0,0.55},{1109,0.15},{1319,0.55},{1480,0.2},{1319,0.2},{1109,0.2},{988,0.2},{1109,0.85},	{1,0.8}, //6               5          3           5          1           6         5                  5     {1480,0.55},	{1319,0.55},{1109,0.15},{1319,0.15},{880,0.55},{740,0.15},{659,0.55},{0,0.3},{659,0.85},//6            1           2                    2{740,0.15},	{880,0.35},	{988,0.55}, {0,0.3},{988,0.55},//2           6            3           5           6          5             5{988,0.15},{1480,0.35},	{1109,0.55},{1319,0.15},{1480,0.35},{1319,0.55},  {1319,0.8}, {1319,0.8},{0,0.8},{0,0.8},{0,0.8},
};void setup() {pinMode(beep_pin, OUTPUT);     //设置引脚为输出模式 
}void loop(){for(int k=0;k<128;k++){        //顺序演奏128音符float d=YUEPU_TSYJ[k].Duration; for(int D=0;D<int(d*YUEPU_TSYJ[k].freq);D++){   //演奏YUEPU[k].freq的音符，时长=dif(YUEPU_TSYJ[k].freq != 0){    //演奏音符//频率转化为时间间隔,1秒=500000微秒*2。一半高电平，一半低电平，所以用500000/音符频率。int freq_to_us=int(500000/YUEPU_TSYJ[k].freq);digitalWrite(beep_pin,HIGH); //一半高电平delayMicroseconds(freq_to_us);digitalWrite(beep_pin,LOW);  //一半低电平delayMicroseconds(freq_to_us);}else{                     //停顿digitalWrite(beep_pin,LOW);  //低电平，不发声  // delayMicroseconds(1000);delay(1000);}}}delay(1000);}

vscode esp32 platformio编译方法参考：

第4篇:vscode+platformio搭建esp32 arduino开发环境