Starting Address for main funtion in microcontroller

[ckshivaram]

yes start up code is like bios. usually there is o need to change as it is optimised to perform with good performance.
At reset the bootloader takes care of initialisation and startup code configures reg and port pin configuration and interrupts,,

 

[bluehole]

Ok...
so can I put an analogy as startup code does the same function in embedded C as done by BIOS/BootStrap in OS ??
(Just asking for better understanding.)

yes Only for analogy :wink:

Also,
Datasheet of controller mentions about the reset values of different FSR and default port config at reset.
Doesnt this mean, controller itself takes care of FSR, intr reg and port pin at reset?
If yes, then what kind of setting does start up code do?

Well The Processor/Controller is Dumb. So to initialize it and peripherals, One must write some code. The Tool-chains available minimise the headache of writing those. I mean they supply those( which is developed by their team) to our project.

I have seen startup code in MPLAB for PIC. There was some stack pointers declared(didnt understand whole code though) and some other memory related stuff.

Exactly, When the application executes it needs the memory to be managed. and as it is a small system we fix the position of different memory location in start-up code; any way you can also modify them if you like, but be very careful.

hope this helps.