DTR電平置低(-3--12V),復位
RTS置高(+3-+12V),選擇進入BootLoader
...延時100毫秒
DTR電平變高(+3-+12V)釋放復位
RTS維持高
開始連接...5, 接收到:79 1F
在串口COM6連接成功@115200bps，耗時795毫秒
晶片內BootLoader版本號：3.1
晶片PID：00000419  STM32F4xxx_43xx
讀出的選項字節:
EFAA1055EFAA1055FF3F00C0FF3F00C0
開始全片擦除(全片擦除時間會比較長，請耐心等候!)
全片擦除成功
開始去除防寫
去除防寫成功
DTR電平置低(-3--12V),復位
RTS置高(+3-+12V),選擇進入BootLoader
...延時100毫秒
DTR電平變高(+3-+12V)釋放復位
RTS維持高
開始連接...5, 接收到:79 1F
在串口COM6連接成功@115200bps，耗時842毫秒
晶片內BootLoader版本號：3.1
晶片PID：00000419  STM32F4xxx_43xx
讀出的選項字節:
EFAA1055EFAA1055FF3F00C0FF3F00C0
第889毫秒，已準備好
共寫入679KB,進度100%,耗時280193毫秒
寫入選項字節： FF AA 00 55 FF AA 00 55 FF FF 00 00 FF FF 00 00
成功寫入選項字節
寫入的選項字節:
FFAA0055FFAA0055FFFF0000FFFF0000
從08000000開始運行失敗...可能是因為剛寫了選項字節!!!
www.mcuisp.com(全脫機手持編程器EP968,全球首創)向您報告，命令執行完畢，一切正常

讀器件信息：

現在，我正在嘗試點亮LED燈。

【程序】
#include "stm32f4xx.h"

void SystemInit(void)
{
}

int main(void)
{
    RCC_AHB1ENR |= (1 << 7);
   
    GPIOH_MODER &= ~(0x03 << (2 * 10));
    GPIOH_MODER |= (1 << 2 * 10);
   
    GPIOH_OTYPER &= ~(1 << 1 * 10);
    GPIOH_OTYPER |= (0 << 1 * 10);
   
    GPIOH_OSPEEDR &= ~(0x03 << 2 * 10);
    GPIOH_OSPEEDR |= (0 << 2 * 10);
   
    GPIOH_PUPDR &= ~(0x03 << 2 * 10);
    GPIOH_PUPDR |= (1 << 2 * 10);
   
    GPIOH_BSSR |= (1 << 16 << 10);
   
    while (1);
    return 0;
}

可見，STM32點亮LED要比C51和AVR複雜很多倍。

【編譯錯誤】
*** Using Compiler 'V5.06 update 1 (build 61)', folder: 'C:\Keil_v5\ARM\ARMCC\Bin'
Build target 'Target 1'
compiling led.c...
C:\Keil_v5\ARM\PACK\Keil\STM32F4xx_DFP\2.7.0\Drivers\CMSIS\Device\ST\STM32F4xx\Include\stm32f429xx.h(192): error:  #5: cannot open source input file "core_cm4.h": No such file or directory
  #include "core_cm4.h"             /* Cortex-M4 processor and core peripherals */
led.c: 0 warnings, 1 error
".\Objects\led.axf" - 1 Error(s), 0 Warning(s).
Target not created.
Build Time Elapsed:  00:00:14

*** Using Compiler 'V5.06 update 1 (build 61)', folder: 'C:\Keil_v5\ARM\ARMCC\Bin'
Build target 'Target 1'
compiling led.c...
led.c(9): error:  #20: identifier "RCC_AHB1ENR" is undefined
      RCC_AHB1ENR |= (1 << 7);
led.c(11): error:  #20: identifier "GPIOH_MODER" is undefined
      GPIOH_MODER &= ~(0x03 << (2 * 10));
led.c(14): error:  #20: identifier "GPIOH_OTYPER" is undefined
      GPIOH_OTYPER &= ~(1 << 1 * 10);
led.c(17): error:  #20: identifier "GPIOH_OSPEEDR" is undefined
      GPIOH_OSPEEDR &= ~(0x03 << 2 * 10);
led.c(20): error:  #20: identifier "GPIOH_PUPDR" is undefined
      GPIOH_PUPDR &= ~(0x03 << 2 * 10);
led.c(23): error:  #20: identifier "GPIOH_BSSR" is undefined
      GPIOH_BSSR |= (1 << 16 << 10);
led.c(26): warning:  #111-D: statement is unreachable
      return 0;
led.c(27): warning:  #1-D: last line of file ends without a newline
  }
led.c: 2 warnings, 6 errors
".\Objects\led.axf" - 6 Error(s), 2 Warning(s).
Target not created.
Build Time Elapsed:  00:00:01

#include "stm32f4xx.h"

//#define PERIPH_BASE ((unsigned int)0x40000000)
#define AHB1PERIPH_BASE (PERIPH_BASE + 0x00020000)
#define GPIOH_BASE (AHB1PERIPH_BASE + 0x1C00)
#define GPIOH_MODER *(unsigned int*)(GPIOH_BASE+0x00)
#define GPIOH_OTYPER *(unsigned int*)(GPIOH_BASE+0x04)
#define GPIOH_OSPEEDR *(unsigned int*)(GPIOH_BASE+0x08)
#define GPIOH_PUPDR *(unsigned int*)(GPIOH_BASE+0x0C)
#define GPIOH_IDR *(unsigned int*)(GPIOH_BASE+0x10)
#define GPIOH_ODR *(unsigned int*)(GPIOH_BASE+0x14)
#define GPIOH_BSRR *(unsigned int*)(GPIOH_BASE+0x18)
#define GPIOH_LCKR *(unsigned int*)(GPIOH_BASE+0x1C)
#define GPIOH_AFRL *(unsigned int*)(GPIOH_BASE+0x20)
#define GPIOH_AFRH *(unsigned int*)(GPIOH_BASE+0x24)
#define RCC_BASE (AHB1PERIPH_BASE + 0x3800)
#define RCC_AHB1ENR *(unsigned int*)(RCC_BASE+0x30)


void SystemInit(void)
{
}

int main(void)
{
    RCC_AHB1ENR |= (1 << 7);
    
    GPIOH_MODER &= ~(0x03 << (2 * 10));
    GPIOH_MODER |= (1 << 2 * 10);
    
    GPIOH_OTYPER &= ~(1 << 1 * 10);
    GPIOH_OTYPER |= (0 << 1 * 10);
    
    GPIOH_OSPEEDR &= ~(0x03 << 2 * 10);
    GPIOH_OSPEEDR |= (0 << 2 * 10);
    
    GPIOH_PUPDR &= ~(0x03 << 2 * 10);
    GPIOH_PUPDR |= (1 << 2 * 10);
    
    GPIOH_BSRR |= (1 << 16 << 10);
    
    while (1);
}

*** Using Compiler 'V5.06 update 1 (build 61)', folder: 'C:\Keil_v5\ARM\ARMCC\Bin'
Build target 'Target 1'
compiling led.c...
linking...
Program Size: Code=244 RO-data=444 RW-data=0 ZI-data=1024  
FromELF: creating hex file...
".\Objects\led.axf" - 0 Error(s), 0 Warning(s).
Build Time Elapsed:  00:00:01