nicla-system: Add function to check if board runs on battery.

Author: sebromero

libraries/Nicla_System/examples/NiclaSenseME_BatteryStatus/NiclaSenseME_BatteryStatus.ino

@@ -222,6 +222,11 @@ void loop()
     bool isCharging = nicla::getOperatingStatus() == OperatingStatus::Charging;
     Serial.print("Battery is charging: ");
     Serial.println(isCharging ? "Yes" : "No");
+
+    bool runsOnBattery = nicla::runsOnBattery();
+    Serial.print("Runs on battery: ");
+    Serial.println(runsOnBattery ? "Yes" : "No");
+
 
     Serial.println("----------------------");
   }

libraries/Nicla_System/src/Nicla_System.cpp

@@ -153,6 +153,10 @@ bool nicla::enableCharging(uint16_t mA, bool disableNtc)
   return _pmic.getFastChargeControlRegister() == _fastChargeRegisterData;
 }
 
+bool nicla::runsOnBattery() {
+  return _pmic.runsOnBattery(BQ25120A_ADDRESS);
+}
+
 uint8_t nicla::getBatteryFaults() {
   // Skips the mask bits (4 LSBs)
   return (_pmic.getFaultsRegister() >> 4) & 0b1111;

libraries/Nicla_System/src/Nicla_System.h

@@ -61,6 +61,13 @@ class nicla {
    */
   static bool enableCharging(uint16_t mA = 20, bool disableNtc = true);
 
+  /**
+   * @brief Determines if the board is charged from the battery.
+   * 
+   * @return true If the board is powered from the battery. False, when powered from USB / VIN.
+   */
+  static bool runsOnBattery();
+
   /**
    * @brief Enables or disables the negative temperature coefficient (NTC) thermistor.
    * NTCs are used to prevent the batteries from being charged at temperatures that are too high or too low.