reworking initial calibration and setting cal values from EEPROM

lib/nvm/src/NvmEeprom.cpp

@@ -26,6 +26,7 @@ void writeCalibration(const JoystickCalibration &cal) {
 
 void readNvm(NonVolatileMemory &nvm)
 {
+    nvm.calData.validMarker = 0;
     for (size_t ii = 0; ii < sizeof(NonVolatileMemory); ii++)
     {
         nvm.rawBytes[ii] = EEPROM.read(ii);

lib/nvm/src/NvmEeprom.hpp

@@ -23,16 +23,36 @@ struct JoystickAxisCalibration
     bool valid() const;
 } __attribute__((packed));
 
+
+/// calibration of min/max for single axis analog signals with no mid point
+/// ie: a potentiometer
+struct LinearAnalogCalibration {
+    uint16_t min;
+    uint16_t max;
+    inline bool valid() const { return min < max; }
+} __attribute__((packed));
+
 struct JoystickCalibration
 {
     JoystickAxisCalibration x;
     JoystickAxisCalibration y;
 } __attribute__((packed));
 
+static constexpr uint32_t VALID_MARKER_DEFAULT = 0xcafecall;
+
 union NonVolatileMemory
 {
-    JoystickCalibration joystickCal;
+    struct Calibration {
-    uint8_t rawBytes[sizeof(JoystickCalibration)] = {};
+        /// place hard-coded start marker at the beginning of the data
+        /// to indicate validity
+        uint32_t validMarker = VALID_MARKER_DEFAULT;
+        JoystickCalibration joystickCal;
+        LinearAnalogCalibration linearCal;
+    } __attribute__((packed)) calData;
+
+    uint8_t rawBytes[NonVolatileMemory::Calibration] = {};
+
+    inline bool valid() const { return calData.validMarker == VALID_MARKER_DEFAULT; }
 };
 
 /// @brief Write the provided struct to EEPROM

src/main.cpp

@@ -11,9 +11,9 @@
 AlignedJoy joystick_1(0, 1); /// X on A0, Y on A1
 ArduinoLEDMatrix ledMatrix;
 
-void runJoystickCalibrationRoutine(AlignedJoy &joy)
+/// Run calibration on the provided joystick. Save the results to the provided calibration
+bool runJoystickCalibrationRoutine(AlignedJoy &joy, JoystickCalibration &cal)
 {
-    // JOYSTICK CALIBRATION
     /*
      * Start the joystick calibration in the center position. Use this method only if the calibration of the axles is desired (axesCalibration).
      */
@@ -50,11 +50,12 @@ void runJoystickCalibrationRoutine(AlignedJoy &joy)
      */
     if (joy.axesCalibration(TIME_CAL_2))
     {
-        Serial.println("Calibration succesfully!!");
+        Serial.println("Calibration succesfull!!");
     }
     else
     {
         Serial.println("Calibration failed!!");
+        return false;
     }
 
     // Print all points calibrated
@@ -79,15 +80,14 @@ void runJoystickCalibrationRoutine(AlignedJoy &joy)
     Serial.print(" | max -> ");
     Serial.println(joy.getCalibratedPoint(Y, MAX));
 
-    // save values to NVM
+    // save values to cal struct
-    JoystickCalibration cal = {};
     cal.x.min = joy.getCalibratedPoint(X, MIN);
     cal.x.mid = joy.getCalibratedPoint(X, MID);
     cal.x.max = joy.getCalibratedPoint(X, MAX);
     cal.y.min = joy.getCalibratedPoint(Y, MIN);
     cal.y.mid = joy.getCalibratedPoint(Y, MID);
     cal.y.max = joy.getCalibratedPoint(Y, MAX);
-    writeCalibration(cal);
+    return true;
 }
 
 void setup()
@@ -102,17 +102,32 @@ void setup()
     }
     ledMatrix.play(true);
 
-    // retrieve joystic calibration values or run calibration and save results
+    // retrieve current calibration values
     NonVolatileMemory nvm = {};
-    bool calibrationInvalid = true;
+    readNvm(nvm);
-    do {
-        readNvm(nvm);
-        calibrationInvalid = !nvm.joystickCal.x.valid() || !nvm.joystickCal.y.valid();
-        if (calibrationInvalid) {
-            runJoystickCalibrationRoutine(joystick_1);
-        }
 
+    // run joystick calibration if needed
+    bool calibrationInvalid = nvm.valid();
+    do {
+        calibrationInvalid |= !nvm.joystickCal.x.valid() || !nvm.joystickCal.y.valid();
+        if (calibrationInvalid) {
+            calibrationInvalid |= !runJoystickCalibrationRoutine(joystick_1, nvm.calData.joystickCal);
+        }
     } while (calibrationInvalid);
+    // ensure calibration has been applied
+    // TODO: API doesnt allow setting configured midpoint...
+    joystick_1.setCalibratedPoint(axis_t::X, point_t::MIN, nvm.calData.joystickCal.x.min);
+    joystick_1.setCalibratedPoint(axis_t::X, point_t::MID, nvm.calData.joystickCal.x.mid);
+    joystick_1.setCalibratedPoint(axis_t::X, point_t::MAX, nvm.calData.joystickCal.x.max);
+    joystick_1.setCalibratedPoint(axis_t::Y, point_t::MIN, nvm.calData.joystickCal.y.min);
+    joystick_1.setCalibratedPoint(axis_t::Y, point_t::MID, nvm.calData.joystickCal.y.mid);
+    joystick_1.setCalibratedPoint(axis_t::Y, point_t::MAX, nvm.calData.joystickCal.y.max);
+
+    // run analog lever calibration if needed
+
+
+    // write NVM in the event any values were updated
+    writeNvm(nvm);
 }
 
 void loop()