Keil uVision Tutorial:
The startup.s assembly code listing used for the First Tutorial. A full line-by-line decoding/explanation of this file is provide here.



Stack_Size EQU 0x00000401
               AREA STACK,NOINIT,READWRITE,ALIGN=3
__stack_limit
Stack_Mem       SPACE Stack_Size
__initial_sp

; Vector Table Mapped to Address 0 at Reset
 AREA RESET, DATA, READONLY
 EXPORT __Vectors
 EXPORT __Vectors_End
 EXPORT __Vectors_Size
__Vectors DCD __initial_sp ; Top of Stack
          DCD Reset_Handler ; Reset Handler
       
__Vectors_End

__Vectors_Size EQU __Vectors_End - __Vectors
                AREA |.text|, CODE, READONLY
Reset_Handler   PROC
                                EXPORT Reset_Handler [Weak]
                                IMPORT __main
                                LDR R0, =__main
                                BX  R0
                                ENDP
                EXPORT   __stack_limit
                EXPORT   __initial_sp

                                END