added possibility to save and load the data

from flash for compass calibration

lib/calibrateCompass/calibrateCompass.cpp

@@ -61,8 +61,10 @@ void CalibrateCompass::loop() {
     if (changed)
         this->lastChange = millis();
 
-    if (millis() - this->lastChange > this->maxTimeWithoutChange)
+    if (millis() - this->lastChange > this->maxTimeWithoutChange) {
         this->state = State::Finished;
+        this->newData = true;
+    }
 }
 
 void CalibrateCompass::start() {
@@ -98,6 +100,37 @@ void CalibrateCompass::reset() {
     this->state = State::Ready;
 }
 
+void CalibrateCompass::saveData() {
+    if (!this->newData)
+        return;
+
+    Preferences preferences;
+    preferences.begin("compassCalibration", false);
+    
+    preferences.putInt("xLow", this->data.data[0][0]);
+    preferences.putInt("xHigh", this->data.data[0][1]);
+    preferences.putInt("yLow", this->data.data[1][0]);
+    preferences.putInt("yHigh", this->data.data[1][1]);
+    preferences.putInt("zLow", this->data.data[2][0]);
+    preferences.putInt("zHigh", this->data.data[2][1]);
+
+    preferences.end();
+}
+
+void CalibrateCompass::loadData() {
+    Preferences preferences;
+    preferences.begin("compassCalibration", true);
+
+    this->data.data[0][0] = preferences.getInt("xLow", 0);
+    this->data.data[0][1] = preferences.getInt("xHigh", 0);
+    this->data.data[1][0] = preferences.getInt("yLow", 0);
+    this->data.data[1][1] = preferences.getInt("yHigh", 0);
+    this->data.data[2][0] = preferences.getInt("zLow", 0);
+    this->data.data[2][1] = preferences.getInt("zHigh", 0);
+
+    preferences.end();
+}
+
 void CalibrateCompass::clearData() {
     for (uint8_t i = 0; i < 3; i++) {
         this->data.data[i][0] = 0;

lib/calibrateCompass/calibrateCompass.h

@@ -12,6 +12,7 @@
 #pragma once
 
 #include <QMC5883LCompass.h>
+#include <Preferences.h>
 
 class CalibrateCompass {
     public:
@@ -32,6 +33,8 @@ class CalibrateCompass {
         void useData();
         void resetData();
         void reset();
+        void saveData();
+        void loadData();
 
         State getState() const { return this->state; }
         CallibrationData getCallibrationData() const { return this->data; }
@@ -43,6 +46,7 @@ class CalibrateCompass {
 
         void clearData();
 
+        bool newData = false;
         const uint16_t maxTimeWithoutChange = 5000;
         uint32_t lastChange = 0;
 };