Major cleanup

Author: rpoisel

.gitmodules

@@ -1,6 +0,0 @@
-[submodule "Tick"]
-	path = Tick
-	url = https://github.com/geekfactory/Tick.git
-[submodule "SPI"]
-	path = SPI
-	url = https://github.com/geekfactory/SPI.git

CMakeLists.txt

@@ -0,0 +1,10 @@
+cmake_minimum_required(VERSION 3.6)
+project(PID LANGUAGES C VERSION 1.0.0)
+
+add_library(PID STATIC
+    PID.c
+)
+
+set_target_properties(PID PROPERTIES
+    POSITION_INDEPENDENT_CODE TRUE
+)

PID.c

@@ -18,6 +18,7 @@
 	Author e-mail: ruben at geekfactory dot mx
  */
 #include "PID.h"
+#include "PID_Support.h"
 
 pid_t pid_create(pid_t pid, float* in, float* out, float* set, float kp, float ki, float kd)
 {
@@ -28,28 +29,32 @@ pid_t pid_create(pid_t pid, float* in, float* out, float* set, float kp, float k
 
 	pid_limits(pid, 0, 255);
 
+        pid->tickspersecond = pid_ticks_per_second();
+
 	// Set default sample time to 100 ms
-	pid->sampletime = 100 * (TICK_SECOND / 1000);
+	pid->sampletime = 100 * (pid->tickspersecond / 1000);
 
 	pid_direction(pid, E_PID_DIRECT);
 	pid_tune(pid, kp, ki, kd);
 
-	pid->lasttime = tick_get() - pid->sampletime;
+	pid->lasttime = pid_ticks_get() - pid->sampletime;
 
 	return pid;
 }
 
 bool pid_need_compute(pid_t pid)
 {
 	// Check if the PID period has elapsed
-	return(tick_get() - pid->lasttime >= pid->sampletime) ? true : false;
+	return(pid_ticks_get() - pid->lasttime >= pid->sampletime) ? true : false;
 }
 
 void pid_compute(pid_t pid)
 {
 	// Check if control is enabled
 	if (!pid->automode)
-		return false;
+        {
+            return;
+        }
 
 	float in = *(pid->input);
 	// Compute error
@@ -73,7 +78,7 @@ void pid_compute(pid_t pid)
 	(*pid->output) = out;
 	// Keep track of some variables for next execution
 	pid->lastin = in;
-	pid->lasttime = tick_get();;
+	pid->lasttime = pid_ticks_get();;
 }
 
 void pid_tune(pid_t pid, float kp, float ki, float kd)
@@ -83,7 +88,7 @@ void pid_tune(pid_t pid, float kp, float ki, float kd)
 		return;
 
 	//Compute sample time in seconds
-	float ssec = ((float) pid->sampletime) / ((float) TICK_SECOND);
+	float ssec = ((float) pid->sampletime) / ((float) pid->tickspersecond);
 
 	pid->Kp = kp;
 	pid->Ki = ki * ssec;
@@ -99,10 +104,10 @@ void pid_tune(pid_t pid, float kp, float ki, float kd)
 void pid_sample(pid_t pid, uint32_t time)
 {
 	if (time > 0) {
-		float ratio = (float) (time * (TICK_SECOND / 1000)) / (float) pid->sampletime;
+		float ratio = (float) (time * (pid->tickspersecond / 1000)) / (float) pid->sampletime;
 		pid->Ki *= ratio;
 		pid->Kd /= ratio;
-		pid->sampletime = time * (TICK_SECOND / 1000);
+		pid->sampletime = time * (pid->tickspersecond / 1000);
 	}
 }
 

PID.h

@@ -19,24 +19,10 @@
  */
 #ifndef PID_H
 #define PID_H
-/*-------------------------------------------------------------*/
-/*		Includes and dependencies			*/
-/*-------------------------------------------------------------*/
-#include "Tick/Tick.h"
+
 #include <stdbool.h>
 #include <stdint.h>
 
-/*-------------------------------------------------------------*/
-/*		Macros and definitions				*/
-/*-------------------------------------------------------------*/
-
-/*-------------------------------------------------------------*/
-/*		Typedefs enums & structs			*/
-/*-------------------------------------------------------------*/
-
-/**
- * Defines if the controler is direct or reverse
- */
 enum pid_control_directions {
 	E_PID_DIRECT,
 	E_PID_REVERSE,
@@ -47,36 +33,34 @@ enum pid_control_directions {
  * posible using different structures for each controller
  */
 struct pid_controller {
-	// Input, output and setpoint
-	float * input; //!< Current Process Value
-	float * output; //!< Corrective Output from PID Controller
-	float * setpoint; //!< Controller Setpoint
-	// Tuning parameters
-	float Kp; //!< Stores the gain for the Proportional term
-	float Ki; //!< Stores the gain for the Integral term
-	float Kd; //!< Stores the gain for the Derivative term
-	// Output minimum and maximum values
-	float omin; //!< Maximum value allowed at the output
-	float omax; //!< Minimum value allowed at the output
-	// Variables for PID algorithm
-	float iterm; //!< Accumulator for integral term
-	float lastin; //!< Last input value for differential term
-	// Time related
-	uint32_t lasttime; //!< Stores the time when the control loop ran last time
-	uint32_t sampletime; //!< Defines the PID sample time
-	// Operation mode
-	uint8_t automode; //!< Defines if the PID controller is enabled or disabled
+	/*  Input, output and setpoint */
+	float * input; /*  Current Process Value */
+	float * output; /*  Corrective Output from PID Controller */
+	float * setpoint; /*  Controller Setpoint */
+	/*  Tuning parameters */
+	float Kp; /*  Stores the gain for the Proportional term */
+	float Ki; /*  Stores the gain for the Integral term */
+	float Kd; /*  Stores the gain for the Derivative term */
+	/*  Output minimum and maximum values */
+	float omin; /*  Maximum value allowed at the output */
+	float omax; /*  Minimum value allowed at the output */
+	/*  Variables for PID algorithm */
+	float iterm; /*  Accumulator for integral term */
+	float lastin; /*  Last input value for differential term */
+	/*  Time related */
+        uint32_t tickspersecond;
+	uint32_t lasttime; /*  Stores the time when the control loop ran last time */
+	uint32_t sampletime; /*  Defines the PID sample time */
+	/*  Operation mode */
+	uint8_t automode; /*  Defines if the PID controller is enabled or disabled */
 	enum pid_control_directions direction;
 };
 
 typedef struct pid_controller * pid_t;
 
-/*-------------------------------------------------------------*/
-/*		Function prototypes				*/
-/*-------------------------------------------------------------*/
 #ifdef	__cplusplus
 extern "C" {
-#endif
+#endif /* __cplusplus */
 	/**
 	 * @brief Creates a new PID controller
 	 *
@@ -184,7 +168,6 @@ extern "C" {
 
 #ifdef	__cplusplus
 }
-#endif
+#endif /* __cplusplus */
 
-#endif
-// End of Header file
+#endif /* PID_H */

PID_Support.h

@@ -0,0 +1,17 @@
+#ifndef PID_SUPPORT_H
+#define PID_SUPPORT_H
+
+#include <stdint.h>
+
+#ifdef	__cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+uint32_t pid_ticks_per_second(void); /* tbd by code using this library */
+uint32_t pid_ticks_get(void); /* tbd by code using this library */
+
+#ifdef	__cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* PID_SUPPORT_H */