auto-adjust lightMeter sensitivity

src/main.cpp

@@ -181,6 +181,22 @@ void getSensorMeasurements() {
 
   if (light_active) {
     sensor_readings.lux = lightMeter.readLightLevel();
+    // auto-adjust sensitivity
+    if (sensor_readings.lux < 0) {
+      Serial.println("Error reading light level");
+    } else if (sensor_readings.lux > 40000.0) {
+      if (lightMeter.setMTreg(32)) {
+        Serial.println(F("Setting MTReg to low value for high light environment"));
+      }
+    } else if (sensor_readings.lux <= 10.0) {
+      if (lightMeter.setMTreg(138)) {
+        Serial.println(F("Setting MTReg to high value for low light environment"));
+      }
+    } else { // if (sensor_readings.lux > 10.0)
+      if (lightMeter.setMTreg(69)) {
+        Serial.println(F("Setting MTReg to default value for normal light environment"));
+      }
+    }
   }
 
   if (sds_active) {