Merge pull request #2114 from mavlink/pr-fix-battery-voltage

Fix battery voltage, included extended voltages

src/mavsdk/plugins/telemetry/telemetry_impl.cpp

@@ -1221,11 +1221,20 @@ void TelemetryImpl::process_battery_status(const mavlink_message_t& message)
                                        static_cast<float>(NAN) :
                                        bat_status.temperature * 1e-2f; // cdegC to degC
     new_battery.voltage_v = 0.0f;
-    for (int i = 0; i < 255; i++) {
-        if (bat_status.voltages[i] == std::numeric_limits<uint16_t>::max())
+    for (int i = 0; i < 10; ++i) {
+        if (bat_status.voltages[i] == std::numeric_limits<uint16_t>::max()) {
             break;
+        }
         new_battery.voltage_v += static_cast<float>(bat_status.voltages[i]) * 1e-3f;
     }
+
+    for (int i = 0; i < 4; ++i) {
+        // A value of 1 means 0 mV.
+        if (bat_status.voltages_ext[i] > 1) {
+            new_battery.voltage_v += static_cast<float>(bat_status.voltages_ext[i]) * 1e-3f;
+        }
+    }
+
     new_battery.remaining_percent = bat_status.battery_remaining;
     new_battery.current_battery_a = (bat_status.current_battery == -1) ?
                                         static_cast<float>(NAN) :