BLDC Controller Snapshot

const int N_OF_COILS = 3;

struct BrushlessDCMotor
{
  int hal_pins[N_OF_COILS];
  //positive and negative coil pins
  int pos_coil_pins[N_OF_COILS];
  int neg_coil_pins[N_OF_COILS];
  
  // The current value of each hal sensor and coil output
  int hal_values[N_OF_COILS];
  int coil_values[N_OF_COILS];
};

/*struct Pid
{
  int p;
  int i;
  int d;
}*/

struct BrushlessDCMotor bldc;
//struct Pid pid;
int speed_pwm_value = 0;
int speed_pwm_pin = 9;

void setup() {
  pid.p = 0.1;
  pid.i = 0;
  pid.d = 0.1;
  
  bldc.hal_pins[0] = 0;
  bldc.hal_pins[1] = 1;
  bldc.hal_pins[2] = 2;
  
  bldc.pos_coil_pins[0] = 3;
  bldc.neg_coil_pins[0] = 4;
  bldc.pos_coil_pins[1] = 5;
  bldc.neg_coil_pins[1] = 6;
  bldc.pos_coil_pins[2] = 7;
  bldc.neg_coil_pins[2] = 8;
  
  for (int i = 0; i < N_OF_COILS; i++)
  {
    pinMode(bldc.hal_pins[i], INPUT);
    pinMode(bldc.pos_coil_pins[i], OUTPUT);
    pinMode(bldc.neg_coil_pins[i], OUTPUT);
    bldc.hal_values[i] = 0;
    bldc.coil_values[i] = 0;
  }
  
  Serial.begin(9600)
}

void loop() {
  //Polling the hal
  for (int i = 0; i < N_OF_COILS; i++)
  {
    bldc.hal_values[i] = digitalRead(bldc.hal_pins[i]);
  }
  //Updating the motor control outputs
  updateCoils();
  //Polling for serial speed control
  if (Serial.available() > 0)
  {
    c = Serial.read();
    if (c=='+') speed_pwm_value = (speed_pwm_value+1)%255;
    if (c=='-' && speed_pwm_value>0) speed_pwm_value -= 1;
    //Sending the speed pwm
    analogWrite(speed_pwm_pin, speed_pwm_value);
  }
}

//Computes the value a coil should be set to to continue spinning the motor.
//positive coil[i] = hal[i] and ( not hal[i+1] )
//negative coil[i] = hal[i+1] and ( not hal[i+2] );
#define coilValue(hal1, hal2) ( hal1 & (1^hal2) )

//Sets the value of a coil
#define setPosCoil(bldc, coil_index, value) if (bldc.coil_values[coil_index] != value) digitalWrite(bldc.pos_coil_pins[coil_index], value); bldc.coil_values[coil_index] = value
#define setNegCoil(bldc, coil_index, value) if (bldc.coil_values[coil_index] == value) digitalWrite(bldc.neg_coil_pins[coil_index], value); bldc.coil_values[coil_index] = !value

//Updates the digital outputs controlling each of the BLDC motor controller half hbridges to reflect updates in the hal values
void updateCoils()
{
  for (int i = 0; i< N_OF_COILS; i++)
  {
    setPosCoil( bldc, i, coilValue( bldc.hal_values[i], bldc.hal_values[(i+1)%N_OF_COILS] ) );
    setNegCoil( bldc, i, coilValue( bldc.hal_values[i+1]%N_OF_COILS, bldc.hal_values[(i)] ) );
  }
}

Arduino:1.8.1 (Windows 7), Kart:"Arduino/Genuino Uno"

C:\Users\User\Documents\Arduino\sketch_mar21a\sketch_mar21a.ino: In function 'void setup()':

sketch_mar21a:28: error: 'pid' was not declared in this scope

pid.p = (0).1;

^

sketch_mar21a:53: error: expected ';' before '}' token

}

^

C:\Users\User\Documents\Arduino\sketch_mar21a\sketch_mar21a.ino: In function 'void loop()':

sketch_mar21a:66: error: 'c' was not declared in this scope

 c = Serial.read();

 ^

exit status 1
'pid' was not declared in this scope

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