serialport and restart

Hello
When the computer restart or shutdown does he sends any message to the serial port
(before restating or shtting down )
I have a microcontroller circuit connected to the computer through a serial port in which I let two led’s exchange their works after every second and this continues in an endless loop ,but if the user restart the computer I need to let the microcontroller program restart from the top of its program (prog.asm) too
How can I do that?
i am using window 7, the microcontroller is pic 16f883,i have two program one is c# and the other is assembly pic program the c# program sends messege to the pic program (and is located in the StartUp directory),assume the pic program is to do job A followed by job B. Job B is to alternat two led's forever,but if the user restart the computer the pic would be still working in Job B whic is not my desired ,i have to added a command inside the endless loop(in pic assembly program)or may be start an interrupt in which i could write
goto top_of_Pic_program ;
therefore i need some message from computer to inform the pic that the computer
has started from over so the pic program must start from the top too.i am using pin 2 and 3 of the serial port to read and write connected to rs232 ic which is connected to the 16f883. no error in either program but i want to improve it

Tags: Microcontroller