c++ - Arduino:如果在构造函数中使用this-> object.attach(pin)，则带有Servo的类会破坏伺服行为

我对解决方案有疑问，但是我不理解该解决方案。它可能类似于Arduino: initialise custom object in constructor，但我认为这不是同一问题。

上下文如下。我正在用Arduino开发板控制一个小腿机器人。每条腿都是一个包含两个伺服器的对象“ MChLeg”。伺服通过库进行控制。

问题是：如果我在构造函数中分配了伺服，程序可以正常编译，但是伺服的运行方式很疯狂（我想我破坏了伺服调度）；如果我在构造函数之外分配伺服，一切都很好。

我在下面仅列出了C ++类的一部分，它是唯一在工作版本和非工作版本之间更改的类。

初始程序（在构造函数中分配的伺服），代码有问题：

#include <Arduino.h>
#include <Servo.h>

class MChLeg{
    int kneeIndex, hipIndex;
    int kneeAngle, hipAngle;
    Servo kneeServo;
    Servo hipServo;
public:
    MChLeg(int, int); // (knee servo index, hip servo index); use 0 if no servo
    ~MChLeg();
    void setLeg(int, int); // (knee angle, hip angle); in degrees, 0-180, 90 is straight
    void rollLeg();
};

MChLeg::MChLeg(int x, int y){
    this->kneeIndex = x;
    this->hipIndex = y;
    if (this->kneeIndex != 0) {
        this->kneeServo.attach(this->kneeIndex);
        this->kneeServo.write(90);   // this line can be removed with no impact on issue
    }
    if (this->hipIndex != 0) {
        this->hipServo.attach(this->hipIndex);
        this->hipServo.write(90);    // this line can be removed with no impact on issue
    }
}

新代码（使用方法分配的伺服），代码运行良好：

#include <Arduino.h>
#include <Servo.h>

class MChLeg{
    int kneeIndex, hipIndex;
    int kneeAngle, hipAngle;
    Servo kneeServo;
    Servo hipServo;
public:
    MChLeg();
    ~MChLeg();
    void assignLeg(int, int); // (knee servo index, hip servo index); use 0 if no servo
    void setLeg(int, int); // (knee angle, hip angle); in degrees, 0-180, 90 is straight
    void rollLeg();
};

MChLeg::MChLeg(){
    this->kneeIndex = 0;
    this->hipIndex = 0;
}

void MChLeg::assignLeg(int x, int y){
    if (this->kneeIndex != 0) {
        this->kneeServo.detach();
    }
    if (this->hipIndex != 0) {
        this->hipServo.detach();
    }
    this->kneeIndex = x;
    this->hipIndex = y;
    if (this->kneeIndex != 0) {
        this->kneeServo.attach(this->kneeIndex);
    }
    if (this->hipIndex != 0) {
        this->hipServo.attach(this->hipIndex);
    }
}

为什么第二个代码比第一个更好？

调用代码：

// Include application, user and local libraries
#include <Servo.h>
#include "MChButton.h"
#include "MChLeg.h"


// pin connections
const int buttonIndex = 2; //pin for button
const int greenLed = 3;//pin for green Led
const int yellowLed = 4;//pin for yellow Led
const int redLed = 5;//pin for red Led
const int servoPin1 = 9;//pin for servo
const int servoPin2 = 10;//pin for servo
const int servoPin3 = 11;//pin for servo


//define persitent objects
MChButton theButton(buttonIndex); // declare the switch pin as an input
MChLeg rightLeg; // declare right leg - was 'MChLeg rightLeg(0, servoPin1);' in first version
MChLeg leftLeg;  // declare left leg - was 'MChLeg leftLeg(servoPin2, servoPin3);' in first version


// Setup phase
void setup(){

    // declare the LED pins as outputs
    pinMode(greenLed,OUTPUT);
    pinMode(yellowLed,OUTPUT);
    pinMode(redLed,OUTPUT);

    leftLeg.assignLeg(0, servoPin1); //right knee - hip - did not exist in first version
    rightLeg.assignLeg(servoPin2, servoPin3); //right knee - hip - did not exist in first version

}

// Loop phase
void loop(){

    //state machine counter (persistant)
    static int machinestate = 0;
    const int machinestateMax = 4; //max statemachine
    const int machinestateMax1 = machinestateMax+1; //max statemachine for modulo counting

    //check if there is an event, if there is one increment state machine counter and mark event done
    //statemachine counter is limited for machinestateMac (modulus)
    if (theButton.buttonEventGet()==true) {
        machinestate = ++machinestate % machinestateMax1;
    }

    // set LEDs and Legs according to state
    switch (machinestate) {
        case 0:{
            digitalWrite(greenLed, HIGH); // turn the green LED on pin 3 on
            digitalWrite(yellowLed, LOW);  // turn the red LED on pin 4 off
            digitalWrite(redLed, LOW);  // turn the red LED on pin 5 off
            leftLeg.setLeg(10, 10); // set leg to 0°
            rightLeg.setLeg(10, 10); //set leg to 0°
            break;
        }
        case 1:{
            digitalWrite(greenLed, HIGH);
            digitalWrite(yellowLed, HIGH);
            digitalWrite(redLed, LOW);
            leftLeg.setLeg(45, 45);
            rightLeg.setLeg(45, 45);
            break;
        }
        default:{ // detect if I did it wrong :-)
            digitalWrite(greenLed, HIGH);
            digitalWrite(yellowLed, HIGH);
            digitalWrite(redLed, HIGH);
        }
    }
    delay(10);
}

谢谢你的帮助。

最佳答案

我现在没有Arduino，但我记得遇到了同样的问题。

据我所记得，我在构造函数中使用for loop来处理无效的数组。因此，我结束了只逐一分配值的工作。

如果使用if statement，我认为是您的问题。

今天晚上我回家时，我将尝试其他不同的事情。

编辑-2015/01/08

我进行了一些测试，以尝试重现我正在谈论的问题，但是没有成功。我将保留我的答案，因为可能没有解决方案。

关于c++ - Arduino:如果在构造函数中使用this-> object.attach(pin)，则带有Servo的类会破坏伺服行为，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/27769400/