How can I install a event handle in the init-code

Thanks for response, I wanna update the program befor the main program(boot loader like), and when I update the program it will bypass the "bootloader". So I add this program to the init code. And I use the bf609;

Thanks for response, I wanna update the program befor the main program(boot loader like), and when I update the program it will bypass the "bootloader". So I add this program to the init code. And I use the bf609;