Your answer is incomplete. Only refer to the assembly of 5 1 series, because the assembly of different manufacturers is different. For example, for eLong, it will be counted as soon as it is indicated by @. These symbols are just a specific symbol. In the assembly of chips from different manufacturers, these *, #, @,%, ... are just a specific symbol of the manufacturer when assembling. It should be aimed at the manufacturer's microcontroller and explain the location of the symbol in order to answer your questions.