added voltage multiplier to gui and set defaults

usermods/Battery/battery_defaults.h

@@ -26,6 +26,15 @@
   #endif
 #endif
 
+//the default ratio for the voltage divider
+#ifndef USERMOD_BATTERY_VOLTAGE_MULTIPLIER
+  #ifdef ARDUINO_ARCH_ESP32
+    #define USERMOD_BATTERY_VOLTAGE_MULTIPLIER 2.0f
+  #else //ESP8266 boards
+    #define USERMOD_BATTERY_VOLTAGE_MULTIPLIER 4.2f
+  #endif
+#endif
+
 #ifndef USERMOD_BATTERY_MAX_VOLTAGE
   #define USERMOD_BATTERY_MAX_VOLTAGE 4.2f
 #endif

usermods/Battery/usermod_v2_Battery.h

@@ -31,8 +31,8 @@ class UsermodBattery : public Usermod
     float voltage = maxBatteryVoltage;
     // between 0 and 1, to control strength of voltage smoothing filter
     float alpha = 0.05f;
-    // multiplyer for the voltage divider that is in place between ADC pin and battery, default will be 2 but might be adapted to readout voltages over ~5v ESP32 or ~6.6v ESP8266
+    // multiplier for the voltage divider that is in place between ADC pin and battery, default will be 2 but might be adapted to readout voltages over ~5v ESP32 or ~6.6v ESP8266
-    float voltageMultiplyer = 2.0f;
+    float voltageMultiplier = USERMOD_BATTERY_VOLTAGE_MULTIPLIER;
     // mapped battery level based on voltage
     int8_t batteryLevel = 100;
     // offset or calibration value to fine tune the calculated voltage
@@ -130,8 +130,8 @@ class UsermodBattery : public Usermod
           if (pinManager.allocatePin(batteryPin, false, PinOwner::UM_Battery)) {
             DEBUG_PRINTLN(F("Battery pin allocation succeeded."));
             success = true;
-            //use calibrated millivolts analogread on esp32 (150 mV ~ 2450 mV default) and divide by 1000 to get from milivolts to volts and multiply by voltage divider and apply calibration value
+            //use calibrated millivolts analogread on esp32 (150 mV ~ 2450 mV default) and divide by 1000 to get from milivolts to volts and multiply by voltage divider ratio and apply calibration value
-            voltage = (analogReadMilliVolts(batteryPin) / 1000.0f) * voltageMultiplyer  + calibration;
+            voltage = (analogReadMilliVolts(batteryPin) / 1000.0f) * voltageMultiplier  + calibration;
           }
 
         if (!success) {
@@ -142,8 +142,8 @@ class UsermodBattery : public Usermod
         }
       #else //ESP8266 boards have only one analog input pin A0
         pinMode(batteryPin, INPUT);
-        //use analog read on esp8266 ( 150 mV ~ 3000mV no attenuation options) and divide by ADC precision 1023 and multiply by 3v ADC max voltage and apply calibration value
+        //use analog read on esp8266 ( 150 mV ~ 3000mV no attenuation options) and divide by ADC precision 1023 and multiply by voltage divider ratio and apply calibration value
-        voltage = (analogRead(batteryPin) / 1023.0f) * 3.3f * voltageMultiplyer + calibration;
+        voltage = (analogRead(batteryPin) / 1023.0f) * voltageMultiplier + calibration;
       #endif
 
       nextReadTime = millis() + readingInterval;
@@ -185,12 +185,12 @@ class UsermodBattery : public Usermod
 
 #ifdef ARDUINO_ARCH_ESP32
       // use calibrated millivolts analogread on esp32 (150 mV ~ 2450 mV default) and divide by 1000 to get from milivolts to volts and multiply by voltage divider and apply calibration value
-      rawValue = (analogReadMilliVolts(batteryPin) / 1000.0f) * voltageMultiplyer + calibration;
+      rawValue = (analogReadMilliVolts(batteryPin) / 1000.0f) * voltageMultiplier + calibration;
       // filter with exponential smoothing because ADC in esp32 is fluctuating too much for a good single readout
       voltage = voltage + alpha * (rawValue - voltage);
 #else
       // use analog read on esp8266 ( 150 mV ~ 3000mV no attenuation options) and divide by ADC precision 1023 and multiply by 3v ADC max voltage and apply calibration value
-      rawValue = (analogRead(batteryPin) / 1023.0f) * 3.0f * voltageMultiplyer + calibration;
+      rawValue = (analogRead(batteryPin) / 1023.0f) * voltageMultiplier + calibration;
       // filter with exponential smoothing 
       voltage = voltage + alpha * (rawValue - voltage);
 #endif
@@ -367,6 +367,7 @@ class UsermodBattery : public Usermod
       battery[F("max-voltage")] = maxBatteryVoltage;
       battery[F("capacity")] = totalBatteryCapacity;
       battery[F("calibration")] = calibration;
+      battery[F("voltage-multiplier")] = voltageMultiplier;
       battery[FPSTR(_readInterval)] = readingInterval;
       
       JsonObject ao = battery.createNestedObject(F("auto-off"));               // auto off section
@@ -443,6 +444,7 @@ class UsermodBattery : public Usermod
       setMaxBatteryVoltage(battery[F("max-voltage")] | maxBatteryVoltage);
       setTotalBatteryCapacity(battery[F("capacity")] | totalBatteryCapacity);
       setCalibration(battery[F("calibration")] | calibration);
+      setVoltageMultiplier(battery[F("voltage-multiplier")] | voltageMultiplier);
       setReadingInterval(battery[FPSTR(_readInterval)] | readingInterval);
 
       JsonObject ao = battery[F("auto-off")];
@@ -637,6 +639,23 @@ class UsermodBattery : public Usermod
       calibration = offset;
     }
 
+    /*
+     * Set the voltage multiplier value
+     * A multiplier that may need adjusting for different voltage divider setups
+     */
+    void setVoltageMultiplier(float multiplier)
+    {
+      voltageMultiplier = multiplier;
+    }
+
+    /*
+     * Get the voltage multiplier value
+     * A multiplier that may need adjusting for different voltage divider setups
+     */
+    float getVoltageMultiplier()
+    {
+      return voltageMultiplier;
+    }
 
     /*
      * Get auto-off feature enabled status