Diff: PID/PID.cpp

Revision:

62:6c566e6f9664

Parent:

60:20945383ad1b

Child:

81:71e7e98deb2c

--- a/PID/PID.cpp	Tue Oct 13 18:28:39 2015 +0200
+++ b/PID/PID.cpp	Wed Oct 14 13:52:16 2015 +0200
@@ -8,7 +8,7 @@
 //t.start(); // start the timer 
 
 
-PID::PID(float* Input, float* Output, float* Setpoint, float Kp, float Ki, float Kd){
+PID::PID(double* Input, double* Output, double* Setpoint, double Kp, double Ki, double Kd){
 	myOutput = Output;
 	myInput = Input;
 	mySetpoint = Setpoint;
@@ -31,7 +31,7 @@
 	// calculate using sample time frequency (regular intervals)
 	// no more need to modify derivative/int sicne sample time is constant
 //	if(timeChange <=SampleTime){ 
-		float input = *myInput;
+		double input = *myInput;
 		error = *mySetpoint - input;  // get error for proportional
 		ITerm += (ki*error);  // Error for integral (with ki included)
 		// check for integrator windup
@@ -41,7 +41,7 @@
 		// (could still be tuned for derivative kick)
 
 		// compute PID output
-		float output  = kp * error + ITerm + kd * dErr;
+		double output  = kp * error + ITerm + kd * dErr;
 		// make sure output is allso within min/max
 		if(output> outMax) output=outMax;
 		else if(output<outMin) output=outMin;
@@ -53,7 +53,7 @@
 //	else return false;
 }
 
-void PID::SetTunings(float Kp, float Ki, float Kd)
+void PID::SetTunings(double Kp, double Ki, double Kd)
 {
 	kp = Kp;
 	ki = Ki * SampleTime; // change PID parameters according to sample time
@@ -61,17 +61,17 @@
 }
 
 
-void PID::SetSampleTime(float NewSampleTime){
+void PID::SetSampleTime(double NewSampleTime){
 	if (NewSampleTime > 0 ){
 		// change ratios for parameters for better computation in compute()
-		float ratio = NewSampleTime/SampleTime;
+		double ratio = NewSampleTime/SampleTime;
 		ki *= ratio;
 		kd /= ratio;
 		SampleTime = NewSampleTime;
 	}
 }
 
-void PID::SetOutputLimits(float min, float max){
+void PID::SetOutputLimits(double min, double max){
 	if (min > max) return;
 	outMin = min;
 	outMax = max;
@@ -102,14 +102,14 @@
 	else if(ITerm<outMin) ITerm=outMin;
 }
 
-float PID::getKp(){
+double PID::getKp(){
 	return kp;
 }
 	
-float PID::getKi(){
+double PID::getKi(){
 	return ki/SampleTime;
 }
 
-float PID::getKd(){
+double PID::getKd(){
 	return kd*SampleTime;
 }
\ No newline at end of file