WIP: start cpp refactoring

main.cpp

@@ -0,0 +1,84 @@
+#include <stdio.h>
+#include <stdlib.h> 
+#include <array>
+#include "pico/stdlib.h"
+
+using namespace std;
+
+#define POLL_PERIOD 50 //time between polls (ms)
+#define MAX_STORED_VALUES 10 //number of stored values to calculate e_dot and e_dot_dot values
+
+/*
+trying to keep the code clean, so some conventions:
+classes: PascalCase
+function: camelCase
+var names: snake_case
+*/
+
+class CustomArray {
+    int* items;    
+    int size;
+
+    public:
+    CustomArray(int s) {
+        size = s;
+        items = (int*) malloc(s * sizeof(int));
+        for (int i = 0; i < s; i++ )
+        {
+            items[i] = 0;
+        }
+    }
+};
+
+class PID {
+    private:
+        int kp, ki, kd, pwm_pin, thermistor_pin, index, desired_temp;
+        bool on;
+        CustomArray error_array;
+
+    int calculate_integral(int* array) {
+        int sum = 0;
+
+        for (int i = 0; i < MAX_STORED_VALUES; i++ ) {
+            sum += array[i];
+        }
+
+        sum *= POLL_PERIOD;
+        return sum;
+    }
+    
+    public:
+        PID(int kp) {
+            error_array = new CustomArray(MAX_STORED_VALUES);
+            this.kp = kp;
+        }
+
+        int calulatePid( int x ) {
+            int e = desired_temp-x; 
+
+            int e_dot = (e - error_array[0]) / POLL_PERIOD;
+            int e_int = calculate_integral(error_array);
+        
+
+            return e * kp + e_dot * kd + e_int * ki;
+        }
+};
+
+void init() {
+    gpio_init(25);
+    gpio_set_dir(25, GPIO_OUT);
+}
+
+int main()
+{
+    stdio_init_all();
+
+
+    while (true) {
+        //printf("Hello, world!\n");
+        gpio_put(25, 0);
+        sleep_ms(250);
+        gpio_put(25, 1);
+        sleep_ms(250);
+    }
+}