学习STM32F769DK-OTA例程之APP中断向量表重映射

2019-04-17

【小记】

　　APP的IAR工程中的中断向量表偏移是在系统库中的 __iar_program_start 处实现的

　　启动代码 stm32f769xx.s

 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;
 ;; Default interrupt handlers.
 ;;
         THUMB
         PUBWEAK Reset_Handler
         SECTION .text:CODE:NOROOT:REORDER()
 Reset_Handler

         LDR     R0, =SystemInit
         BLX     R0
         LDR     R0, =__iar_program_start
         BX      R0

         PUBWEAK NMI_Handler
         SECTION .text:CODE:NOROOT:REORDER()

　　经调试看到 __iar_program_start 的反汇编

 Reset_Handler:
     0x80385d0: 0x4801         LDR.N     R0, [PC, #0x4]          ; SystemInit
         BLX     R0
     0x80385d2: 0x4780         BLX       R0
         LDR     R0, =__iar_program_start
     0x80385d4: 0x4801         LDR.N     R0, [PC, #0x4]          ; __iar_program_start
         BX      R0
     0x80385d6: 0x4700         BX        R0
         SECTION .text:CODE:NOROOT:REORDER()
     0x80385d8: 0x0802586d     DC32      SystemInit
         SECTION .text:CODE:NOROOT:REORDER()
     0x80385dc: 0x080385f9     DC32      __iar_program_start
     0x80385e0: 0x70636573     DC32      0x70636573 ()
     0x80385e4: 0x72363532     DC32      0x72363532 ()
     0x80385e8: 0x00000031     DC32      0x31 ()
     0x80385ec: 0x72617453     DC32      0x72617453 ()
     0x80385f0: 0x00000074     DC32      0x74 ()
     0x80385f4: 0x00544f49     DC32      0x544f49 ()
 __iar_program_start:
     0x80385f8: 0xf3af 0x8000  NOP.W
     0x80385fc: 0xf7ff 0xff90  BL        __iar_init_vfp          ; 0x8038520
     0x8038600: 0xf7ff 0xffb0  BL        ?main                   ; 0x8038564
 APBPrescTable:
     0x8038604: 0x00000000     DC32      0x0 ()
     0x8038608: 0x04030201     DC32      0x4030201 ()
     0x803860c: 0x002e0000     DC32      0x2e0000 ()
     0x8038610: 0x0043         DC16                            ; 'C.'
         B WWDG_IRQHandler

 __iar_init_vfp:
     0x8038520: 0xf64e 0x5188  MOVW      R1, #              ; 0xed88
     0x8038524: 0xf2ce 0x0100  MOVT      R1, #              ; 0xe000
     0x8038528: 0x6808         LDR       R0, [R1]
     0x803852a: 0xf440 0x0070  ORR.W     R0, R0, #       ; 0xf00000
     0x803852e: 0x6008         STR       R0, [R1]
     0x8038530: 0xf3bf 0x8f4f  DSB
     0x8038534: 0xf3bf 0x8f6f  ISB
     0x8038538: 0xf04f 0x7000  MOV.W     R0, #           ; 0x2000000
     0x803853c: 0xeee1 0x0a10  VMSR      FPSCR, R0
     0x8038540: 0x4770         BX        LR
     0x8038542: 0x0000         MOVS      R0, R0
 Region$$Table$$Base:
     0x8038544: 0xfffdb3e7     DC32      0xfffdb3e7 (-)
     0x8038548: 0x000220dc     DC32      0x220dc ()
     0x803854c: 0x20000204     DC32      xStart
     0x8038550: 0x00000000     DC32      0x0 ()
     0x8038554: 0xfffdb2b7     DC32      0xfffdb2b7 (-)
     0x8038558: 0x00000262     DC32      0x262 ()
     0x803855c: 0x000001a2     DC32      0x1a2 ()
     0x8038560: 0x20000000     DC32      global_hooks
 ?main:
 Region$$Table$$Limit:
 __cmain:
     0x8038564: 0xf000 0xf80d  BL        __low_level_init        ; 0x8038582
     0x8038568: 0x2800         CMP       R0, #
     0x803856a: 0xd001         BEQ.N     _call_main              ; 0x8038570
     0x803856c: 0xf7ff 0xffb2  BL        __iar_data_init3        ; 0x80384d4