DeviceHardware

Hardware generation of a headset, as the device itself reports it in the Device Information Service Model Number string (0x2A24): a decimal code shared with the BrainAccess C core (ba_device_model in device_model.h) and written by the firmware (device_information_api.h, device_number_list).

The advertised name ("BA HALO 108") only says which montage the headset has (DeviceModel). The code says which sensors sit in the stream-packet footer and how they scale: a HALO V3 has an IMU that the earlier HALOs lack, and the V3 IMU (ICM-42670-P) counts 64× finer than the ADXL343 on the V2 boards. Every byte after the EEG payload depends on this, so the decoder and the unit conversion both key on it — exactly as the C core does (DeviceFeatures.h, eeg_manager.cpp PutAccelerometerData / PutGyroData).

Code 3 (EMG) is a montage this SDK does not model and resolves to null; legacyDefault is what a device is assumed to be when the string is missing or unparseable — the V2 board of its model, which is every unit shipped before the code carried a generation.

Code 6 is the C core's MINI_V3. That board ships as its own product, the EXG8 (advertised "BA EXG8 "), so it resolves only for a device advertising as EXG8; a development unit on that board still advertising as "BA MINI" falls back to MINI_V2 like any mismatched code.