Arduino類重定義錯誤

Question

在我的Arduino IDE中，我建立了一個程序，它通過一個移位寄存器運行八個LED，現在正在嘗試創建一個類來控制移位寄存器。到目前爲止，我已經創建了文件，並創建了一個構造函數的類的一些功能，但是當我嘗試驗證碼的IDE說，我在這裏重新定義類shiftreg是錯誤消息：

In file included from Lab9_step3.cpp:97: 
shiftreg.h:2: error: redefinition of 'class shiftreg' 
shiftreg.h:3: error: previous definition of 'class shiftreg' 

我對lab_9代碼：

/*  --------------------------------------------------------- 
*  | Arduino Experimentation Kit Example Code    | 
*  | CIRC-05 .: 8 More LEDs :. (74HC595 Shift Register) | 
*  --------------------------------------------------------- 
* 
* We have already controlled 8 LEDs however this does it in a slightly 
* different manner. Rather than using 8 pins we will use just three 
* and an additional chip. 
* 
* 
*/ 
#include "shiftreg.h" 

//Pin Definitions 
//Pin Definitions 
//The 74HC595 uses a serial communication 
//link which has three pins 
shiftreg a(2, 3, 4); 

int sensorPin = 0; // select the input pin for the potentiometer 
int sensorValue = 0; // variable to store the value coming from the sensor 




/* 
* setup() - this function runs once when you turn your Arduino on 
* We set the three control pins to outputs 
*/ 
void setup() 
{ 
    a.pinmode(); 
} 

/* 
* loop() - this function will start after setup finishes and then repeat 
* we set which LEDs we want on then call a routine which sends the states to the 74HC595 
*/ 
void loop()      // run over and over again 
{ 
    for(int i = 0; i < 256; i++){ 
    a.update(i); 

    // read the value from the sensor: 
    sensorValue = analogRead(sensorPin); 

    delay(sensorValue); 
    } 
} 



    /****************************** 

    /* 
    * updateLEDsLong() - sends the LED states set in ledStates to the 74HC595 
    * sequence. Same as updateLEDs except the shifting out is done in software 
    * so you can see what is happening. 
    */ 
// void updateLEDsLong(int value){ 
//  digitalWrite(latch, LOW); //Pulls the chips latch low 
//  for(int i = 0; i < 8; i++){ //Will repeat 8 times (once for each bit) 
//  int bit = value & B10000000; //We use a "bitmask" to select only the eighth 
//         //bit in our number (the one we are addressing this time thro 
//      //ugh 
//  value = value << 1;   //we move our number up one bit value so next time bit 7 will 
//      // be 
//         //bit 8 and we will do our math on it 
//  if(bit == 128){digitalWrite(data, HIGH);} //if bit 8 is set then set our data pin high 
//  else{digitalWrite(data, LOW);}   //if bit 8 is unset then set the data pin low 
//  digitalWrite(clock, HIGH);    //the next three lines pulse the clock pin 
//  delay(1); 
//  digitalWrite(clock, LOW); 
//  } 
//  digitalWrite(latch, HIGH); //pulls the latch high shifting our data into being displayed 
// } 
//  
//  
// //These are used in the bitwise math that we use to change individual LEDs 
// //For more details http://en.wikipedia.org/wiki/Bitwise_operation 
// int bits[] = {B00000001, B00000010, B00000100, B00001000, B00010000, B00100000, B01000000, B10000000}; 
// int masks[] = {B11111110, B11111101, B11111011, B11110111, B11101111, B11011111, B10111111, B01111111}; 
// /* 
//  * changeLED(int led, int state) - changes an individual LED 
//  * LEDs are 0 to 7 and state is either 0 - OFF or 1 - ON 
//  */ 
//  void changeLED(int led, int state){ 
//  ledState = ledState & masks[led]; //clears ledState of the bit we are addressing 
//  if(state == ON){ledState = ledState | bits[led];} //if the bit is on we will add it to le 
//      //dState 
//  updateLEDs(ledState);    //send the new LED state to the shift register 
//  } 
//  **********************************/ 

和我的shiftreg.h代碼：

/*Shift Register 
*/    (Error occurs here) 
class shiftreg (and here) 
{ 
    private: 
    //Pin Definitions 
    //Pin Definitions 
    //The 74HC595 uses a serial communication 
    //link which has three pins 
    int data; 
    int clock; 
    int latch; 

    public: 
    shiftreg (int _data, int _clock, int _latch); 
    void update(int value); 
    void pinmode(); 
}; 

和我的shiftreg.cpp代碼：

#include "shiftreg.h" 

/*shiftreg constructor: 
*/ 
shiftreg::shiftreg (int _data, int _clock, int _latch) 
{ 
    data = _data; 
    clock = _clock; 
    latch = _latch; 

    //Used for single LED manipulation 
    int ledState = 0; 
    const int ON = HIGH; 
    const int OFF = LOW; 
} 

/* 
* updateLEDs() - sends the LED states set in ledStates to the 74HC595 
* sequence 
*/ 
void shiftreg::update(int value) 
{ 
    digitalWrite(latch, LOW);  //Pulls the chips latch low 
    shiftOut(data, clock, MSBFIRST, value); //Shifts out the 8 bits to the shift register 
    digitalWrite(latch, HIGH); //Pulls the latch high displaying the data 
} 

/* 
*/ 
void shiftreg::pinmode() 
{ 
    pinMode(data, OUTPUT); 
    pinMode(clock, OUTPUT); 
    pinMode(latch, OUTPUT); 
} 

感謝您的幫助！

Answer 1

根據錯誤消息，您在Lab9_step3.cpp的第97行包含shiftreg.h。那上面的96條線是什麼？錯誤可能在某處。

如果我不得不猜測，我會說，你直接或間接地包括shiftreg.h兩次（或更多）Lab9_step3.cpp，並且錯誤的發生是因爲在頭文件中沒有包含警衛。

嘗試添加以下內容shiftreg.h

#ifndef SHIFTREG_H 
#define SHIFTREG_H 

class shiftreg 
{ 
    // ... 
}; 

#endif