where is the error here????

Forum 2005-2010 (read only) Hardware Troubleshooting
1 
#define ROLL 7
#define THROTTLE 3
#define MOTOR1 2
#define MOTOR2 4
#define MOTOR3 6
#define MOTOR4 8
#define TMAX 1700
#define TMIN 910
#define RMAX 1890
#define RMIN 1085
#define RCENTRE 1476

int throttle1,roll1;
float dt,setpoint,pro_var,pterm,Kp,Kd,dterm,error[2],input;
int gyro_iroll[4]={0,0,0,0},diff=0;
float roll_raw=0,gyro_froll[4];
unsigned long last=0,now=0;
int q,i,j;

float gyro_roll()
{
  last=now;
  now=micros();
  diff=now-last;
  roll_raw = (roll_raw + (((gyro_froll[3] + 2*gyro_froll[2] + 2*gyro_froll[1] + gyro_froll[0])*roll_diff)/6000000));
  for(q=2;q>=0;q--)
    gyro_froll[q+1]=gyro_froll[q];
  gyro_iroll[0]=analogRead(0);
  gyro_froll[0]=gyro_iroll[0]-361;
//  Serial.println(val);
return roll_raw;
}

int roll_pid(roll1,roll_raw)
{
 setpoint =roll1;
 input =roll_raw;
 dt=0;
 Kp=1.25,Kd=-0.5;

 error[0]=setpoint-input;
 pterm=Kp*error[0];
 dt=(millis()-dt)*1000;
 dterm=Kd*(error[0]-error[1])/dt;
 dt=dt/1000;
 error[1]=error[0];
 pro_var=pterm+dterm;

 return pro_var;
}

void setup()
{
  Serial.begin(4800);
  for(q=0;q<=3;q++)
  {
    gyro_iroll[q]=analogRead(0);
    gyro_froll[q]=gyro_iroll[q]-361;
  }
  pinMode(MOTOR1, OUTPUT);
  pinMode(MOTOR2, OUTPUT);
  pinMode(MOTOR3, OUTPUT);
  pinMode(MOTOR4, OUTPUT);
  pinMode(THROTTLE,INPUT);
  pinMode(ROLL,INPUT);
  pinMode(0,INPUT);
}

void loop()
{
 int val1,val2,val3,val4;
 throttle1=pulseIn(THROTTLE,HIGH);
 roll1=pulseIn(ROLL,HIGH);

 if((roll1<RMAX) && (roll1>RMIN))
 {
   if((roll1>RCENTRE-14) && (roll1<RCENTRE+14))
   {
     roll1=0;
   }
   else if((throttle1-TMIN)>(TMAX-throttle1))
     {
       roll1=map(roll1,RMIN,RMAX,-(TMAX-throttle1),(TMAX-throttle1));
     }
     else 
     {
       roll1=map(roll1,RMIN,RMAX,-(throttle1-TMIN),(throttle1-TMIN));
     }
 }

 do
 {
   gyro_roll_raw=gyro_roll();
   roll_pd_value=roll_pid(roll1,gyro_roll_raw);
 
   val1=throttle1;
   val2=throttle1+roll_pd_value;
   val3=throttle1;
   val4=throttle1-roll_pd_value;
  
   digitalWrite(MOTOR1,HIGH);
   delayMicroseconds(val1);
   digitalWrite(MOTOR1,LOW);
   digitalWrite(MOTOR2,HIGH);
   delayMicroseconds(val2);
   digitalWrite(MOTOR2,LOW);
   digitalWrite(MOTOR3,HIGH);
   delayMicroseconds(val3);
   digitalWrite(MOTOR3,LOW);
   digitalWrite(MOTOR4,HIGH);
   delayMicroseconds(val4);
   digitalWrite(MOTOR4,LOW);
 }while(roll_pd_value!=throttle)
}

I know there are many many other errors but this one is not justified.
I'm not even using the variable roll1 in that function..
When i compile it shows this error and highlights the 10th row.
I'm using arduino 17 if that counts...
PLZ Help Out ..

Thanks in advance

2

this one is not justified.

Well, you may want to take that back... The problem is here:

[glow]int roll_pid(roll1,roll_raw)[/glow]{
 setpoint =roll1;
 input =roll_raw;
 dt=0;

You don't define what roll1 is (or roll_raw for that matter)

The hilight is just on the wrong line (wrong function even...)

3

You should declare the variable type in the head of the function defination. So:-

int roll_pid(roll1,roll_raw)
{
 setpoint =roll1;
 input =roll_raw;
 dt=0;
 Kp=1.25,Kd=-0.5;

Should be:-

int roll_pid(int roll1, int roll_raw)
{
 setpoint =roll1;
 input =roll_raw;
 dt=0;
 Kp=1.25,Kd=-0.5;
4

Are these definitions global variables?

int throttle1,roll1;
float dt,setpoint,pro_var,pterm,Kp,Kd,dterm,error[2],input;
int gyro_iroll[4]={0,0,0,0},diff=0;
float roll_raw=0,gyro_froll[4];
5

Yes, but functions with the same variable name redefine the variable (making them local to the function.)

for example, a global variable:

int iGlobal = 100;

also declared in a function declared like:

void DoSomethingLocal(int iGlobal)
{
   Serial.print(iGlobal);
}

called with

DoSomethingLocal(500);

will print 500, not 100.

6

thanks everyone..
i thot that declaring it globally will help me prevent from having to declare the type again.

thanks again.