基于STM32的寄存器实现点亮LED

1.启动文件

startup_stm32f103xe.s

;******************** (C) COPYRIGHT 2017 STMicroelectronics ********************
;* File Name          : startup_stm32f103xe.s
;* Author             : MCD Application Team
;* Description        : STM32F103xE 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.
;******************************************************************************
;* @attention
;*
;* Copyright (c) 2017-2021 STMicroelectronics.
;* All rights reserved.
;*
;* This software is licensed under terms that can be found in the LICENSE file
;* in the root directory of this software component.
;* If no LICENSE file comes with this software, it is provided AS-IS.
;*
;******************************************************************************

; Amount of memory (in bytes) allocated for Stack
; Tailor this value to your application needs
; <h> Stack Configuration
;   <o> Stack Size (in Bytes) <0x0-0xFFFFFFFF:8>
; </h>

Stack_Size      EQU     0x00000400

                AREA    STACK, NOINIT, READWRITE, ALIGN=3
Stack_Mem       SPACE   Stack_Size
__initial_sp
                                                  
; <h> Heap Configuration
;   <o>  Heap Size (in Bytes) <0x0-0xFFFFFFFF:8>
; </h>

Heap_Size       EQU     0x00000200

                AREA    HEAP, NOINIT, READWRITE, ALIGN=3
__heap_base
Heap_Mem        SPACE   Heap_Size
__heap_limit

                PRESERVE8
                THUMB


; 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
                DCD     NMI_Handler                ; NMI Handler
                DCD     HardFault_Handler          ; Hard Fault Handler
                DCD     MemManage_Handler          ; MPU Fault Handler
                DCD     BusFault_Handler           ; Bus Fault Handler
                DCD     UsageFault_Handler         ; Usage Fault Handler
                DCD     0                          ; Reserved
                DCD     0                          ; Reserved
                DCD     0                          ; Reserved
                DCD     0                          ; Reserved
                DCD     SVC_Handler                ; SVCall Handler
                DCD     DebugMon_Handler           ; Debug Monitor Handler
                DCD     0                          ; Reserved
                DCD     PendSV_Handler             ; PendSV Handler
                DCD     SysTick_Handler            ; SysTick Handler

                ; External Interrupts
                DCD     WWDG_IRQHandler            ; Window Watchdog
                DCD     PVD_IRQHandler             ; PVD through EXTI Line detect
                DCD     TAMPER_IRQHandler          ; Tamper
                DCD     RTC_IRQHandler             ; RTC
                DCD     FLASH_IRQHandler           ; Flash
                DCD     RCC_IRQHandler             ; RCC
                DCD     EXTI0_IRQHandler           ; EXTI Line 0
                DCD     EXTI1_IRQHandler           ; EXTI Line 1
                DCD     EXTI2_IRQHandler           ; EXTI Line 2
                DCD     EXTI3_IRQHandler           ; EXTI Line 3
                DCD     EXTI4_IRQHandler           ; EXTI Line 4
                DCD     DMA1_Channel1_IRQHandler   ; DMA1 Channel 1
                DCD     DMA1_Channel2_IRQHandler   ; DMA1 Channel 2
                DCD     DMA1_Channel3_IRQHandler   ; DMA1 Channel 3
                DCD     DMA1_Channel4_IRQHandler   ; DMA1 Channel 4
                DCD     DMA1_Channel5_IRQHandler   ; DMA1 Channel 5
                DCD     DMA1_Channel6_IRQHandler   ; DMA1 Channel 6
                DCD     DMA1_Channel7_IRQHandler   ; DMA1 Channel 7
                DCD     ADC1_2_IRQHandler          ; ADC1 & ADC2
                DCD     USB_HP_CAN1_TX_IRQHandler  ; USB High Priority or CAN1 TX
                DCD     USB_LP_CAN1_RX0_IRQHandler ; USB Low  Priority or CAN1 RX0
                DCD     CAN1_RX1_IRQHandler        ; CAN1 RX1
                DCD     CAN1_SCE_IRQHandler        ; CAN1 SCE
                DCD     EXTI9_5_IRQHandler         ; EXTI Line 9..5
                DCD     TIM1_BRK_IRQHandler        ; TIM1 Break
                DCD     TIM1_UP_IRQHandler         ; TIM1 Update
                DCD     TIM1_TRG_COM_IRQHandler    ; TIM1 Trigger and Commutation
                DCD     TIM1_CC_IRQHandler         ; TIM1 Capture Compare
                DCD     TIM2_IRQHandler            ; TIM2
                DCD     TIM3_IRQHandler            ; TIM3
                DCD     TIM4_IRQHandler            ; TIM4
                DCD     I2C1_EV_IRQHandler         ; I2C1 Event
                DCD     I2C1_ER_IRQHandler         ; I2C1 Error
                DCD     I2C2_EV_IRQHandler         ; I2C2 Event
                DCD     I2C2_ER_IRQHandler         ; I2C2 Error
                DCD     SPI1_IRQHandler            ; SPI1
                DCD     SPI2_IRQHandler            ; SPI2
                DCD     USART1_IRQHandler          ; USART1
                DCD     USART2_IRQHandler          ; USART2
                DCD     USART3_IRQHandler          ; USART3
                DCD     EXTI15_10_IRQHandler       ; EXTI Line 15..10
                DCD     RTC_Alarm_IRQHandler        ; RTC Alarm through EXTI Line
                DCD     USBWakeUp_IRQHandler       ; USB Wakeup from suspend
                DCD     TIM8_BRK_IRQHandler        ; TIM8 Break
                DCD     TIM8_UP_IRQHandler         ; TIM8 Update
                DCD     TIM8_TRG_COM_IRQHandler    ; TIM8 Trigger and Commutation
                DCD     TIM8_CC_IRQHandler         ; TIM8 Capture Compare
                DCD     ADC3_IRQHandler            ; ADC3
                DCD     FSMC_IRQHandler            ; FSMC
                DCD     SDIO_IRQHandler            ; SDIO
                DCD     TIM5_IRQHandler            ; TIM5
                DCD     SPI3_IRQHandler            ; SPI3
                DCD     UART4_IRQHandler           ; UART4
                DCD     UART5_IRQHandler           ; UART5
                DCD     TIM6_IRQHandler            ; TIM6
                DCD     TIM7_IRQHandler            ; TIM7
                DCD     DMA2_Channel1_IRQHandler   ; DMA2 Channel1
                DCD     DMA2_Channel2_IRQHandler   ; DMA2 Channel2
                DCD     DMA2_Channel3_IRQHandler   ; DMA2 Channel3
                DCD     DMA2_Channel4_5_IRQHandler ; DMA2 Channel4 & Channel5
__Vectors_End

__Vectors_Size  EQU  __Vectors_End - __Vectors

                AREA    |.text|, CODE, READONLY
                
; Reset handler
Reset_Handler   PROC
                EXPORT  Reset_Handler             [WEAK]
                IMPORT  __main
                IMPORT  SystemInit
                LDR     R0, =SystemInit
                BLX     R0               
                LDR     R0, =__main
                BX      R0
                ENDP
                
; Dummy Exception Handlers (infinite loops which can be modified)

NMI_Handler     PROC
                EXPORT  NMI_Handler                [WEAK]
                B       .
                ENDP
HardFault_Handler\
                PROC
                EXPORT  HardFault_Handler          [WEAK]
                B       .
                ENDP
MemManage_Handler\
                PROC
                EXPORT  MemManage_Handler          [WEAK]
                B       .
                ENDP
BusFault_Handler\
                PROC
                EXPORT  BusFault_Handler           [WEAK]
                B       .
                ENDP
UsageFault_Handler\
                PROC
                EXPORT  UsageFault_Handler         [WEAK]
                B       .
                ENDP
SVC_Handler     PROC
                EXPORT  SVC_Handler                [WEAK]
                B       .
                ENDP
DebugMon_Handler\
                PROC
                EXPORT  DebugMon_Handler           [WEAK]
                B       .
                ENDP
PendSV_Handler  PROC
                EXPORT  PendSV_Handler             [WEAK]
                B       .
                ENDP
SysTick_Handler PROC
                EXPORT  SysTick_Handler            [WEAK]
                B       .
                ENDP

Default_Handler PROC

                EXPORT  WWDG_IRQHandler            [WEAK]
                EXPORT  PVD_IRQHandler             [WEAK]
                EXPORT  TAMPER_IRQHandler          [WEAK]
                EXPORT  RTC_IRQHandler             [WEAK]
                EXPORT  FLASH_IRQHandler           [WEAK]
                EXPORT  RCC_IRQHandler             [WEAK]
                EXPORT  EXTI0_IRQHandler           [WEAK]
                EXPORT  EXTI1_IRQHandler           [WEAK]
                EXPORT  EXTI2_IRQHandler           [WEAK]
                EXPORT  EXTI3_IRQHandler           [WEAK]
                EXPORT  EXTI4_IRQHandler           [WEAK]
                EXPORT  DMA1_Channel1_IRQHandler   [WEAK]
                EXPORT  DMA1_Channel2_IRQHandler   [WEAK]
                EXPORT  DMA1_Channel3_IRQHandler   [WEAK]
                EXPORT  DMA1_Channel4_IRQHandler   [WEAK]
                EXPORT  DMA1_Channel5_IRQHandler   [WEAK]
                EXPORT  DMA1_Channel6_IRQHandler   [WEAK]
                EXPORT  DMA1_Channel7_IRQHandler   [WEAK]
                EXPORT  ADC1_2_IRQHandler          [WEAK]
                EXPORT  USB_HP_CAN1_TX_IRQHandler  [WEAK]
                EXPORT  USB_LP_CAN1_RX0_IRQHandler [WEAK]
                EXPORT  CAN1_RX1_IRQHandler        [WEAK]
                EXPORT  CAN1_SCE_IRQHandler        [WEAK]
                EXPORT  EXTI9_5_IRQHandler         [WEAK]
                EXPORT  TIM1_BRK_IRQHandler        [WEAK]
                EXPORT  TIM1_UP_IRQHandler         [WEAK]
                EXPORT  TIM1_TRG_COM_IRQHandler    [WEAK]
                EXPORT  TIM1_CC_IRQHandler         [WEAK]
                EXPORT  TIM2_IRQHandler            [WEAK]
                EXPORT  TIM3_IRQHandler            [WEAK]
                EXPORT  TIM4_IRQHandler            [WEAK]
                EXPORT  I2C1_EV_IRQHandler         [WEAK]
                EXPORT  I2C1_ER_IRQHandler         [WEAK]
                EXPORT  I2C2_EV_IRQHandler         [WEAK]
                EXPORT  I2C2_ER_IRQHandler         [WEAK]
                EXPORT  SPI1_IRQHandler            [WEAK]
                EXPORT  SPI2_IRQHandler            [WEAK]
                EXPORT  USART1_IRQHandler          [WEAK]
                EXPORT  USART2_IRQHandler          [WEAK]
                EXPORT  USART3_IRQHandler          [WEAK]
                EXPORT  EXTI15_10_IRQHandler       [WEAK]
                EXPORT  RTC_Alarm_IRQHandler        [WEAK]
                EXPORT  USBWakeUp_IRQHandler       [WEAK]
                EXPORT  TIM8_BRK_IRQHandler        [WEAK]
                EXPORT  TIM8_UP_IRQHandler         [WEAK]
                EXPORT  TIM8_TRG_COM_IRQHandler    [WEAK]
                EXPORT  TIM8_CC_IRQHandler         [WEAK]
                EXPORT  ADC3_IRQHandler            [WEAK]
                EXPORT  FSMC_IRQHandler            [WEAK]
                EXPORT  SDIO_IRQHandler            [WEAK]
                EXPORT  TIM5_IRQHandler            [WEAK]
                EXPORT  SPI3_IRQHandler            [WEAK]
                EXPORT  UART4_IRQHandler           [WEAK]
                EXPORT  UART5_IRQHandler           [WEAK]
                EXPORT  TIM6_IRQHandler            [WEAK]
                EXPORT  TIM7_IRQHandler            [WEAK]
                EXPORT  DMA2_Channel1_IRQHandler   [WEAK]
                EXPORT  DMA2_Channel2_IRQHandler   [WEAK]
                EXPORT  DMA2_Channel3_IRQHandler   [WEAK]
                EXPORT  DMA2_Channel4_5_IRQHandler [WEAK]

WWDG_IRQHandler
PVD_IRQHandler
TAMPER_IRQHandler
RTC_IRQHandler
FLASH_IRQHandler
RCC_IRQHandler
EXTI0_IRQHandler
EXTI1_IRQHandler
EXTI2_IRQHandler
EXTI3_IRQHandler
EXTI4_IRQHandler
DMA1_Channel1_IRQHandler
DMA1_Channel2_IRQHandler
DMA1_Channel3_IRQHandler
DMA1_Channel4_IRQHandler
DMA1_Channel5_IRQHandler
DMA1_Channel6_IRQHandler
DMA1_Channel7_IRQHandler
ADC1_2_IRQHandler
USB_HP_CAN1_TX_IRQHandler
USB_LP_CAN1_RX0_IRQHandler
CAN1_RX1_IRQHandler
CAN1_SCE_IRQHandler
EXTI9_5_IRQHandler
TIM1_BRK_IRQHandler
TIM1_UP_IRQHandler
TIM1_TRG_COM_IRQHandler
TIM1_CC_IRQHandler
TIM2_IRQHandler
TIM3_IRQHandler
TIM4_IRQHandler
I2C1_EV_IRQHandler
I2C1_ER_IRQHandler
I2C2_EV_IRQHandler
I2C2_ER_IRQHandler
SPI1_IRQHandler
SPI2_IRQHandler
USART1_IRQHandler
USART2_IRQHandler
USART3_IRQHandler
EXTI15_10_IRQHandler
RTC_Alarm_IRQHandler
USBWakeUp_IRQHandler
TIM8_BRK_IRQHandler
TIM8_UP_IRQHandler
TIM8_TRG_COM_IRQHandler
TIM8_CC_IRQHandler
ADC3_IRQHandler
FSMC_IRQHandler
SDIO_IRQHandler
TIM5_IRQHandler
SPI3_IRQHandler
UART4_IRQHandler
UART5_IRQHandler
TIM6_IRQHandler
TIM7_IRQHandler
DMA2_Channel1_IRQHandler
DMA2_Channel2_IRQHandler
DMA2_Channel3_IRQHandler
DMA2_Channel4_5_IRQHandler
                B       .

                ENDP

                ALIGN

;*******************************************************************************
; User Stack and Heap initialization
;*******************************************************************************
                 IF      :DEF:__MICROLIB
                
                 EXPORT  __initial_sp
                 EXPORT  __heap_base
                 EXPORT  __heap_limit
                
                 ELSE
                
                 IMPORT  __use_two_region_memory
                 EXPORT  __user_initial_stackheap
                 
__user_initial_stackheap

                 LDR     R0, =  Heap_Mem
                 LDR     R1, =(Stack_Mem + Stack_Size)
                 LDR     R2, = (Heap_Mem +  Heap_Size)
                 LDR     R3, = Stack_Mem
                 BX      LR

                 ALIGN

                 ENDIF

                 END

 

2.主程序

main.c

#define RCC_BASE        0x40021000
#define RCC_APB2ENR     (*(volatile int *)(RCC_BASE+0x18)) /* 基地址+偏移地址 */
#define GPIOB_BASE      0X40010C00
#define GPIOB_CRL       (*(volatile int *)GPIOB_BASE)
#define GPIOB_ODR       (*(volatile int *)(GPIOB_BASE + 0x0C))

int main(void){
    // 使用GPIOB的PB5点亮LED
    // GPIOB的地址范围是0X40010C00 - 0x40010FFF
    /** GPIO初始化流程
        1.选择GPIO，就是选择GPIO的基地址
      2.使能GPIOB的时钟（时钟使能寄存器(RCC_APB2ENR)）
      3.配置工作模式（CRL和CRH寄存器）
      4.控制GPIO输出高低电平（ODR，BRR，BSRR）
     CRL：低八位端口配置低寄存器
     CRH：高八位端口配置低寄存器
     ODR：端口输出数据寄存器
     BRR：端口位清除寄存器
     BSRR：端口位设置/清除寄存器
    
    **/
        /**
      GPIO端口B：0X40010C00 - 0x40010FFF 
      GPIOB基地址是0X40010C00，GPIOB_ODR地址偏移：0X0C，GPIOB_ODR的地址是0X40010C0C
      RCC_APB2ENR寄存器（RCC地址：0x40021000-0x400213FF 偏移地址：0x18），地址：0x40021018,复位值：0x0000 0000
      GPIOB_CRL寄存器（偏移地址：0x00），地址0X40010C00，复位值：0x44444444
      ODR寄存器（偏移地址：0x0C），地址0X40010C0C，复位值：0x0000 0000
    **/
    
    // 开启GPIOB时钟
    RCC_APB2ENR |= (1<<3);
  // GPIOB_CRL寄存器
    GPIOB_CRL &= ~(0xf<<(4*5));
    GPIOB_CRL |= ((1)<<(4*5));
  // PB5设置为2MHZ的输出模式，输出低电平,寄存器为GPIOB_ODR
    GPIOB_ODR &=~ (1<<5);
    
    
    while(1){
    }
    return 0;
}

void SystemInit(void){
    
}

 完整的代码地址：

https://gitee.com/navysummer/stm32spl