两轮平衡小车心得（一）

1.PinChangeInterrupt.h里面的attachPinChangeInterrupt函数第一个参数是中断号，不是pin码，所以必须用digitalPinToPCINT(PinA_left)包含；
2.arduino原装的attachInterrupt函数只能用2、3 号pin针，如果用了别的针脚则无效！原装自带两个外部中断，这就是使用PinChangeInterrupt库的原因；
3.本代码只提供了霍尔编码器代码，用AN1~BN2针脚得出方向。

#include <MsTimer2.h>
#include <PinChangeInterrupt.h>

int STBY = 8; //使能端
int PWMA = 9; //右电机PWM输出控制脚   
int AIN1 = 7; //右电机正极  
int AIN2 = 6; //右电机负极  
int PWMB = 10; //左电机PWM输出控制脚
int BIN1 = 13; //左电机正极 
int BIN2 = 12; //左电机负极  
#define PinA_left 4  //中断 
#define PinA_right 2 //中断1
int count_right = 0;
int count_left = 0;
float leftSpeed = 0;
float rightSpeed = 0;

void setup(){  
  pinMode(STBY, OUTPUT);  
  pinMode(PWMA, OUTPUT);  
  pinMode(AIN1, OUTPUT);  
  pinMode(AIN2, OUTPUT);  
  pinMode(PWMB, OUTPUT);  
  pinMode(BIN1, OUTPUT);  
  pinMode(BIN2, OUTPUT);  
  pinMode(PinA_left, INPUT);  //测速码盘输入
  pinMode(PinA_right, INPUT);
  attachPinChangeInterrupt(digitalPinToPCINT(PinA_left), Code_left, CHANGE);
  attachInterrupt(digitalPinToInterrupt(PinA_right), Code_right, CHANGE);
  Serial.begin(19200);
  MsTimer2::set(50,countpluse);
  MsTimer2::start();
}

void loop(){  
  runset(1, 155, 1);
  delay(2000);
  runset(1, 55, 0);
  delay(2000);
  runset(2, 155, 1);
  delay(2000);
  runset(2, 55, 0);
  delay(2000);
  stop();
}

void runset(int motor, int speed, int direction){
  digitalWrite(STBY, 1); 
  if(motor==1 && direction== 1){
    digitalWrite(AIN1,1);
    digitalWrite(AIN2,0);
    analogWrite(PWMA, speed); 
  }
  if(motor==2 && direction== 1){
    digitalWrite(BIN1,1);
    digitalWrite(BIN2,0);
    analogWrite(PWMB, speed); 
  }
    if(motor==1 && direction== 0){
    digitalWrite(AIN1,0);
    digitalWrite(AIN2,1);
    analogWrite(PWMA, speed); 
  }
  if(motor==2 && direction== 0){
    digitalWrite(BIN1,0);
    digitalWrite(BIN2,1);
    analogWrite(PWMB, speed); 
  }
}

void stop(){  
  digitalWrite(STBY, LOW);   
}  

void countpluse()
{
  if (digitalRead(AIN1)==1 && digitalRead(AIN2)==0){
    rightSpeed = count_right;
  }
  else if (digitalRead(AIN1)==0 && digitalRead(AIN2)==1){
    rightSpeed = -count_right;
  }
  if (digitalRead(BIN1)==1 && digitalRead(BIN2)==0){
    leftSpeed = count_left;
  }
  else if (digitalRead(BIN1)==0 && digitalRead(BIN2)==1){
    leftSpeed = -count_left;
  }

  count_left = 0;
  count_right = 0;
  Serial.print(leftSpeed);
  Serial.print('\t');
  Serial.println(rightSpeed);
}

void Code_left() {
  count_left ++;
} //左测速码盘计数

void Code_right() {
  count_right ++;
} //右测速码盘计数