Diff: PID.h

Revision:

0:ce3ac53af6e4

Child:

2:359f1f075c72

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/PID.h	Mon May 15 21:21:08 2017 +0000
@@ -0,0 +1,79 @@
+#include "mbed.h"
+#ifndef PID_H_
+#define PID_H_
+
+class PID
+{
+  public:
+ 
+  //Constants used in some of the functions below
+  #define AUTOMATIC 1
+  #define MANUAL    0
+  #define DIRECT  0
+  #define REVERSE  1
+ 
+  //commonly used functions **************************************************************************
+    PID(double*, double*, double*,        // * constructor.  links the PID to the Input, Output, and 
+        double, double, double, int);     //   Setpoint.  Initial tuning parameters are also set here
+    
+    void SetMode(int Mode);               // * sets PID to either Manual (0) or Auto (non-0)
+ 
+    bool Compute();                       // * performs the PID calculation.  it should be
+                                          //   called every time loop() cycles. ON/OFF and
+                                          //   calculation frequency can be set using SetMode
+                                          //   SetSampleTime respectively
+ 
+    void SetOutputLimits(double, double); //clamps the output to a specific range. 0-255 by default, but
+                                          //it's likely the user will want to change this depending on
+                                          //the application
+    
+ 
+ 
+  //available but not commonly used functions ********************************************************
+    void SetTunings(double, double,       // * While most users will set the tunings once in the 
+                    double);              //   constructor, this function gives the user the option
+                                          //   of changing tunings during runtime for Adaptive control
+    void SetControllerDirection(int);     // * Sets the Direction, or "Action" of the controller. DIRECT
+                                          //   means the output will increase when error is positive. REVERSE
+                                          //   means the opposite.  it's very unlikely that this will be needed
+                                          //   once it is set in the constructor.
+    void SetSampleTime(int);              // * sets the frequency, in Milliseconds, with which 
+                                          //   the PID calculation is performed.  default is 100
+                                          
+                                          
+                                          
+  //Display functions ****************************************************************
+    double GetKp();                       // These functions query the pid for interal values.
+    double GetKi();                       //  they were created mainly for the pid front-end,
+    double GetKd();                       // where it's important to know what is actually 
+    int GetMode();                        //  inside the PID.
+    int GetDirection();                   //
+ 
+  private:
+    void Initialize();
+    
+    double dispKp;              // * we'll hold on to the tuning parameters in user-entered 
+    double dispKi;              //   format for display purposes
+    double dispKd;              //
+    
+    double kp;                  // * (P)roportional Tuning Parameter
+    double ki;                  // * (I)ntegral Tuning Parameter
+    double kd;                  // * (D)erivative Tuning Parameter
+ 
+    int controllerDirection;
+ 
+    double *myInput;              // * Pointers to the Input, Output, and Setpoint variables
+    double *myOutput;             //   This creates a hard link between the variables and the 
+    double *mySetpoint;           //   PID, freeing the user from having to constantly tell us
+                                  //   what these values are.  with pointers we'll just know.
+              
+    unsigned long lastTime;
+    double ITerm, lastInput;
+ 
+    unsigned long SampleTime;
+    double outMin, outMax;
+    bool inAuto;
+    Timer t;
+};
+
+#endif
\ No newline at end of file