Simple PID Controller with Integral Windup Supports creating a diagnostics message to send to a GUI

Fork of PidController by James Batchelar

Revision:
5:1206105e20bd
Parent:
4:b590bd8fec6f
--- a/PidController.h	Wed Oct 04 01:13:49 2017 +0000
+++ b/PidController.h	Tue Oct 31 03:46:43 2017 +0000
@@ -41,10 +41,9 @@
 #ifndef PidController_H
 #define PidController_H
 #include "mbed.h"
-#include "math.h"
 
 //-- Constants used in system
-const int RATE = 100;       //--(ms) Time that Calculate mehtod is being called       
+const int RATE = 20;       //--(ms) Time that Calculate mehtod is being called       
 const int AUTOMATIC = 0;    //-- In automatic then PID Controls Output
 const int MANUAL = 1;       //-- In Manual then User Controls Output directly
 
@@ -57,14 +56,14 @@
         /** Constructor
         *
         */
-        PidController(bool);
+        PidController(char);
         
         /** Performs the PID Calculation
         * @param SP - Setpoint (target value) units depends on what PID is controlling
         * @param PV - Process Variable (feedback/ measure value) units depends on what PID is controlling
         * @return Returns If Controller is in Automatic then returns PID controlled signal. In manual returns the user SP multipled by scalar.
         */
-        int Calculate(float SP, float PV, float ManualMV);
+        float Calculate(float SP, float PV, float ManualMV);
         
         /** Update Internal Settings
         * @param Bias - Added to the PID Calculation
@@ -75,7 +74,7 @@
         * @param OutputMax - Maximum Limit for the Output (units are same as setpoint)
         * @param OutputScale - Multiplier at End of PID loop to convert from engineering units to signal (eg PWM duty cycle)   
         */    
-        void UpdateSettings(float Bias, float PropGain, float IntGain, float DiffGain, float OutputMin, float OutputMax, float OutputScale);
+        void UpdateSettings(float Bias, float PropGain, float IntGain, float DiffGain, float OutputMin, float OutputMax);
         
         /** Update Internal Settings
         * @param OutputMin - Minimum Limit for the Output (units are same as setpoint)
@@ -126,13 +125,14 @@
         int elapsedTime;
         
         //-- For PID Calculations
-        bool squareRootOuptut;
-        float bias, scalar;
+        char diagChar;
+        float bias;
         float error;
         float lastInput;
         float accumError;
         float minLimit, maxLimit;
         float K_p,K_i,K_d;
+        float prevError;
     };
     
 #endif