Was your device in 'Overwrite' mode when it got erased/overwritten? In that case BT747 may download the entire log to make sure that it gets all the data.
If you select 'Normal' download mode, BT747 should only download what is reported by the device (well - there is some extra check to check if there is some more data, so it might do a bit more but not much if the rest of the memory is empty).
Was your device in
Was your device in 'Overwrite' mode when it got erased/overwritten? In that case BT747 may download the entire log to make sure that it gets all the data.
If you select 'Normal' download mode, BT747 should only download what is reported by the device (well - there is some extra check to check if there is some more data, so it might do a bit more but not much if the rest of the memory is empty).