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;******************** (C) COPYRIGHT 2016 STMicroelectronics ********************
;* File Name          : startup_stm32f103xb.s
;* Author             : MCD Application Team
;* Version            : V1.4.0
;* Date               : 29-April-2016
;* Description        : STM32F103xB Devices vector table for MDK-ARM toolchain. 
;*                      This module performs:
;*                      - Set the initial SP
;*                      - Set the initial PC == Reset_Handler
;*                      - Set the vector table entries with the exceptions ISR address
;*                      - Configure the clock system
;*                      - Branches to __main in the C library (which eventually
;*                        calls main()).
;*                      After Reset the Cortex-M3 processor is in Thread mode,
;*                      priority is Privileged, and the Stack is set to Main.
;********************************************************************************

; Reset handler
Reset_Handler    PROC
                 EXPORT  Reset_Handler             [WEAK]
     IMPORT  __main
     IMPORT  SystemInit
                 LDR     R0, =SystemInit
                 BLX     R0
                 LDR     R0, =__main // 将main指令集的首地址传给R0
                 BX      R0  　　　　 // pc指针指向R0存储的地址

                 ENDP