AP_BattMonitor: rename VOLT_TIMER to LOW_TIMER

libraries/AP_BattMonitor/AP_BattMonitor.cpp

@@ -143,15 +143,15 @@ const AP_Param::GroupInfo AP_BattMonitor::var_info[] = {
 
 #endif // AP_BATT_MONITOR_MAX_INSTANCES > 1
 
-    // @Param: _VOLT_TIMER
+    // @Param: _LOW_TIMER
     // @DisplayName: Low voltage timeout
     // @Description: This is the timeout in seconds before a low voltage event will be triggered. For aircraft with low C batteries it may be necessary to raise this in order to cope with low voltage on long takeoffs. A value of zero disables low voltage errors.
     // @Units: s
     // @Increment: 1
     // @Range: 0 120
     // @User: Advanced
-    AP_GROUPINFO("_VOLT_TIMER", 21, AP_BattMonitor, _volt_timeout, AP_BATT_LOW_VOLT_TIMEOUT_DEFAULT),
+    AP_GROUPINFO("_LOW_TIMER", 21, AP_BattMonitor, _low_voltage_timeout, AP_BATT_LOW_VOLT_TIMEOUT_DEFAULT),
-        
+
     AP_GROUPEND
 };
 
@@ -312,7 +312,7 @@ bool AP_BattMonitor::exhausted(uint8_t instance, float low_voltage, float min_ca
         // this is the first time our voltage has dropped below minimum so start timer
         if (state[instance].low_voltage_start_ms == 0) {
             state[instance].low_voltage_start_ms = AP_HAL::millis();
-        } else if (_volt_timeout > 0 && AP_HAL::millis() - state[instance].low_voltage_start_ms > uint32_t(_volt_timeout.get())*1000U) {
+        } else if (_low_voltage_timeout > 0 && AP_HAL::millis() - state[instance].low_voltage_start_ms > uint32_t(_low_voltage_timeout.get())*1000U) {
             return true;
         }
     } else {

libraries/AP_BattMonitor/AP_BattMonitor.h

@@ -149,8 +149,7 @@ protected:
     AP_Int32    _pack_capacity[AP_BATT_MONITOR_MAX_INSTANCES];      /// battery pack capacity less reserve in mAh
     AP_Int16    _watt_max[AP_BATT_MONITOR_MAX_INSTANCES];           /// max battery power allowed. Reduce max throttle to reduce current to satisfy this limit
     AP_Int32    _serial_numbers[AP_BATT_MONITOR_MAX_INSTANCES];     /// battery serial number, automatically filled in on SMBus batteries
-
+    AP_Int8     _low_voltage_timeout;                               /// timeout in seconds before a low voltage event will be triggered
-    AP_Int8     _volt_timeout;
 
 private:
     BattMonitor_State state[AP_BATT_MONITOR_MAX_INSTANCES];