Initiate magnetometer based compass calibration from button presses (#5553)

* Initiate magenetometer based compass calibration from button presses

- only active for BMX160 accelerometers on RAK_4631
- replace automatic calibration on power on with button triggered
  calibration
- set 5 presses to trigger 30s calibration
- set 6 presses to trigger 60s calibration (useful if unit is not
  handheld, ie vehicle mounted)
- show calibration time remaining on calibration alert screen

* Fix non RAK 4631 builds

- exclude changes from non RAK 4631 builds
- remove calls to screen when not present

* Fix build on RAK4631_eth_gw

- exclude all compass heading updates on variant without screen

---------

Co-authored-by: Ben Meadors <benmmeadors@gmail.com>

src/ButtonThread.cpp

@@ -190,6 +190,20 @@ int32_t ButtonThread::runOnce()
             case 4:
                 digitalWrite(PIN_EINK_EN, digitalRead(PIN_EINK_EN) == LOW);
                 break;
+#endif
+#if defined(RAK_4631)
+            // 5 clicks: start accelerometer/magenetometer calibration for 30 seconds
+            case 5:
+                if (accelerometerThread) {
+                    accelerometerThread->calibrate(30);
+                }
+                break;
+            // 6 clicks: start accelerometer/magenetometer calibration for 60 seconds
+            case 6:
+                if (accelerometerThread) {
+                    accelerometerThread->calibrate(60);
+                }
+                break;
 #endif
             // No valid multipress action
             default:

src/graphics/Screen.h

@@ -278,6 +278,10 @@ class Screen : public concurrency::OSThread
     bool hasHeading() { return hasCompass; }
 
     long getHeading() { return compassHeading; }
+
+    void setEndCalibration(uint32_t _endCalibrationAt) { endCalibrationAt = _endCalibrationAt; }
+    uint32_t getEndCalibration() { return endCalibrationAt; }
+
     // functions for display brightness
     void increaseBrightness();
     void decreaseBrightness();
@@ -673,6 +677,8 @@ class Screen : public concurrency::OSThread
 
     bool hasCompass = false;
     float compassHeading;
+    uint32_t endCalibrationAt;
+
     /// Holds state for debug information
     DebugInfo debugInfo;
 

src/motion/AccelerometerThread.h

@@ -48,6 +48,13 @@ class AccelerometerThread : public concurrency::OSThread
         setIntervalFromNow(0);
     };
 
+    void calibrate(uint16_t forSeconds)
+    {
+        if (sensor) {
+            sensor->calibrate(forSeconds);
+        }
+    }
+
   protected:
     int32_t runOnce() override
     {

src/motion/BMX160Sensor.cpp

@@ -25,19 +25,21 @@ bool BMX160Sensor::init()
 
 int32_t BMX160Sensor::runOnce()
 {
+#if !defined(MESHTASTIC_EXCLUDE_SCREEN)
     sBmx160SensorData_t magAccel;
     sBmx160SensorData_t gAccel;
 
     /* Get a new sensor event */
     sensor.getAllData(&magAccel, NULL, &gAccel);
 
-#if !defined(MESHTASTIC_EXCLUDE_SCREEN)
-    // experimental calibrate routine. Limited to between 10 and 30 seconds after boot
-    if (millis() > 12 * 1000 && millis() < 30 * 1000) {
+    if (doCalibration) {
+
         if (!showingScreen) {
+            powerFSM.trigger(EVENT_PRESS); // keep screen alive during calibration
             showingScreen = true;
             screen->startAlert((FrameCallback)drawFrameCalibration);
         }
+
         if (magAccel.x > highestX)
             highestX = magAccel.x;
         if (magAccel.x < lowestX)
@@ -50,9 +52,17 @@ int32_t BMX160Sensor::runOnce()
             highestZ = magAccel.z;
         if (magAccel.z < lowestZ)
             lowestZ = magAccel.z;
-    } else if (showingScreen && millis() >= 30 * 1000) {
-        showingScreen = false;
-        screen->endAlert();
+
+        uint32_t now = millis();
+        if (now > endCalibrationAt) {
+            doCalibration = false;
+            endCalibrationAt = 0;
+            showingScreen = false;
+            screen->endAlert();
+        }
+
+        // LOG_DEBUG("BMX160 min_x: %.4f, max_X: %.4f, min_Y: %.4f, max_Y: %.4f, min_Z: %.4f, max_Z: %.4f", lowestX, highestX,
+        // lowestY, highestY, lowestZ, highestZ);
     }
 
     int highestRealX = highestX - (highestX + lowestX) / 2;
@@ -93,12 +103,25 @@ int32_t BMX160Sensor::runOnce()
         heading += 270;
         break;
     }
+
     screen->setHeading(heading);
 #endif
 
     return MOTION_SENSOR_CHECK_INTERVAL_MS;
 }
 
+void BMX160Sensor::calibrate(uint16_t forSeconds)
+{
+#if !defined(MESHTASTIC_EXCLUDE_SCREEN)
+    LOG_DEBUG("BMX160 calibration started for %is", forSeconds);
+
+    doCalibration = true;
+    uint16_t calibrateFor = forSeconds * 1000; // calibrate for seconds provided
+    endCalibrationAt = millis() + calibrateFor;
+    screen->setEndCalibration(endCalibrationAt);
+#endif
+}
+
 #endif
 
 #endif

src/motion/BMX160Sensor.h

@@ -23,6 +23,7 @@ class BMX160Sensor : public MotionSensor
     explicit BMX160Sensor(ScanI2C::FoundDevice foundDevice);
     virtual bool init() override;
     virtual int32_t runOnce() override;
+    virtual void calibrate(uint16_t forSeconds) override;
 };
 
 #else

src/motion/MotionSensor.cpp

@@ -2,6 +2,8 @@
 
 #if !defined(ARCH_PORTDUINO) && !defined(ARCH_STM32WL) && !MESHTASTIC_EXCLUDE_I2C
 
+char timeRemainingBuffer[12];
+
 // screen is defined in main.cpp
 extern graphics::Screen *screen;
 
@@ -37,6 +39,12 @@ void MotionSensor::drawFrameCalibration(OLEDDisplay *display, OLEDDisplayUiState
     display->setTextAlignment(TEXT_ALIGN_LEFT);
     display->setFont(FONT_MEDIUM);
     display->drawString(x, y, "Calibrating\nCompass");
+
+    uint8_t timeRemaining = (screen->getEndCalibration() - millis()) / 1000;
+    sprintf(timeRemainingBuffer, "( %02d )", timeRemaining);
+    display->setFont(FONT_SMALL);
+    display->drawString(x, y + 40, timeRemainingBuffer);
+
     int16_t compassX = 0, compassY = 0;
     uint16_t compassDiam = graphics::Screen::getCompassDiam(display->getWidth(), display->getHeight());
 

src/motion/MotionSensor.h

@@ -40,6 +40,8 @@ class MotionSensor
     // Refer to /src/concurrency/OSThread.h for more information
     inline virtual int32_t runOnce() { return MOTION_SENSOR_CHECK_INTERVAL_MS; };
 
+    virtual void calibrate(uint16_t forSeconds){};
+
   protected:
     // Turn on the screen when a tap or motion is detected
     virtual void wakeScreen();
@@ -53,6 +55,10 @@ class MotionSensor
 #endif
 
     ScanI2C::FoundDevice device;
+
+    // Do calibration if true
+    bool doCalibration = false;
+    uint32_t endCalibrationAt = 0;
 };
 
 namespace MotionSensorI2C