DFPlayer mini MP3模块控制三个按钮代码检验不过去

Question

我运用uno板连接DFPlayer mini MP3模块控制三个按钮完成上一首、下一首、暂停的效果，我自查过很多遍代码了觉得没什么问题，但是验证总是不通过是怎么回事呢，请帮忙看看指教指教！谢谢！

这是我的代码

#include"SoftwareSerial.h"//引入串口头文件1
#include "DFPlayer_Mini_Mp3.h"//2
SoftwareSerial mySerial(10, 11);//3
# define LOW//4
int Pin = 2;//5
int upPin = 3;//6
int downPin = 4;//7
bool a;//布尔8
//9
 void setup (){//10
pinMode(upPin,INPUT);//端口状态11
digitalWrite(upPin,HIGH);//12
pinMode(downPin,INPUT);//13
digitalWrite(downPin,HIGH);//14
pinMode(Pin,INPUT);//15
digitalWrite(Pin,HIGH);//16
Serial.begin(9600);//17
   mySerial.begin (9600);//18
   mp3_set_serial ( mySerial);//19
   delay(1);//20
 mp3_play(1);//21
   }//22
   //23
void loop (){//24
if(digitalRead(upPin)==LOW){//25
delay(20);//26
if(digitalRead(upPin)==LOW){//27
delay(500);//28
 a=!a;//取反29
 if(a==1){//30
 mp3_play();//31
 mp3_set_volume(30);//32
 Serial.print('d');//33
 }//34
 if (a==0){//35
 mp3_stop();//36
 Serial.print('c');//37
 }//38
}//39
 while( digitalRead(upPin)==LOW);//消抖40
     }//41
// 42
   if(digitalRead(downPin)==LOW){//43
       delay(20);//44
       if(digitalRead(downPin)==LOW){//45
         delay(500);//46
           mp3_next();//47
           mp3_set_volume(30);//48
           Serial.print('b');//49
       }//50
       while( digitalRead(downPin)==LOW);//51
   }//52
//53
       if(digitalRead(Pin)==LOW){//54
       delay(20);//55
       if(digitalRead(Pin)==LOW){//56
         delay(500);//57
           mp3_prev();//58
           mp3_set_volume(30);//59
           Serial.print('a');//60
       }//61
       while( digitalRead(Pin)==LOW);//62
       }//63
   }//64
  

下面是编译有误显示的错误信息

Arduino:1.7.8 (Windows 8.1), 板："Arduino Uno"

构建选项已变更，全部重新构建

anjianceshi1-1.ino: In function 'void loop()':

anjianceshi1-1.ino:25:27: error: expected primary-expression before ')' token

anjianceshi1-1.ino:27:27: error: expected primary-expression before ')' token

anjianceshi1-1.ino:40:32: error: expected primary-expression before ')' token

anjianceshi1-1.ino:43:32: error: expected primary-expression before ')' token

anjianceshi1-1.ino:45:36: error: expected primary-expression before ')' token

anjianceshi1-1.ino:51:40: error: expected primary-expression before ')' token

anjianceshi1-1.ino:54:32: error: expected primary-expression before ')' token

anjianceshi1-1.ino:56:32: error: expected primary-expression before ')' token

anjianceshi1-1.ino:62:36: error: expected primary-expression before ')' token

编译有误。

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