DroneCAN Battery: Per-cell (AUX) voltage info not displayed when using multiple battery packs

mohammad_amin · December 8, 2025, 2:01pm

im sending and receiving BatteryInfoAux for two separated batteries but im not getting the battery cell volatages for the second pack in status tab in Mission planner. in status tab there is just one groupe of battery_cellx. i have set the parameters for monitoring both of them, battx_monitor=8, batt_serial_num=my battery_id (1, 2), batt_option = AllowSplitAuxInfo(128) and also the can port parameters. i can see the dronecan messages in mavlinkcan1 inspector and they are valid.
also if i use batt2_monitor individually and disable the batt_monitor, the battery_cellx values are 0. it seems the BatteryInfoAux is handled just for the batt_monitor.

the battx_option parameter have a value for AllowSplitAuxInfo(128) but is not shown in mission planner parameters setting and i entered the value manually.

i guess this file in ardupilot repo is related:

github.com/ArduPilot/ardupilot

libraries/AP_BattMonitor/AP_BattMonitor_DroneCAN.cpp

master


      
          
          void AP_BattMonitor_DroneCAN::handle_battery_info_trampoline(AP_DroneCAN *ap_dronecan, const CanardRxTransfer& transfer, const uavcan_equipment_power_BatteryInfo &msg)
          {
              AP_BattMonitor_DroneCAN* driver = get_dronecan_backend(ap_dronecan, transfer.source_node_id, msg.battery_id);
              if (driver == nullptr) {
                  return;
              }
              driver->handle_battery_info(msg);
          }
          
          void AP_BattMonitor_DroneCAN::handle_battery_info_aux_trampoline(AP_DroneCAN *ap_dronecan, const CanardRxTransfer& transfer, const ardupilot_equipment_power_BatteryInfoAux &msg)
          {
              const auto &batt = AP::battery();
              AP_BattMonitor_DroneCAN *driver = nullptr;
          
              /*
                check for a backend with AllowSplitAuxInfo set, allowing InfoAux
                from a different CAN node than the base battery information
               */
              for (uint8_t i = 0; i < batt._num_instances; i++) {
                  const auto *drv = batt.drivers[i];