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Using a disassembler, find entry points to your new functions for each of these four reference firmwares and add them to the end of those files.
 
'''NOTE'''
 
You can optionally specify the length of the function in words (=instructions) after the entry point. If the function is shorter than 32 instructions, and doesn't end in a simple RET, specifying this should give better matches.
 
'''4) ''' Build.