typedef   signed         char int8_t;
typedef   signedshort     int int16_t;
typedef   signed          int int32_t;
typedef   signed      __int64 int64_t;
 
   
typedef unsigned         char uint8_t;
typedef unsignedshort     int uint16_t;
typedef unsigned          int uint32_t;
typedef unsigned      __int64 uint64_t;
 
   
 
   
   
typedef   signed         char int_least8_t;
typedef   signedshort     int int_least16_t;
typedef   signed          int int_least32_t;
typedef   signed      __int64 int_least64_t;
 
   
typedef unsigned         char uint_least8_t;
typedef unsignedshort     int uint_least16_t;
typedef unsigned          int uint_least32_t;
typedef unsigned      __int64 uint_least64_t;
 
   
 
   
typedef   signed          int int_fast8_t;
typedef   signed          int int_fast16_t;
typedef   signed          int int_fast32_t;
typedef   signed      __int64 int_fast64_t;
 
   
typedef unsigned          int uint_fast8_t;
typedef unsigned          int uint_fast16_t;
typedef unsigned          int uint_fast32_t;
typedef unsigned      __int64 uint_fast64_t;
 
   
typedef   signed          int intptr_t;
typedef unsigned          int uintptr_t;
 
   
typedef   signed      __int64 intmax_t;
typedef unsigned      __int64 uintmax_t;
在百度百科中，我們可以看到 stdint.h 的作用：

二、在 core_cm3.h 文件裏，有如下定義：
 #ifdef__cplusplus
  #define    __I     volatile      
#else
  #define    __I     volatile const    
#endif
#define     __O    volatile    
#define     __IO   volatile    
 
CMSIS IO類型限定詞
IO類限定詞
#define
描述
_I
volatile const
只讀訪問
_O
volatile
只寫訪問
_IO
volatile
讀和寫訪問
stm32變量的定義
 
其中，volatile 的作用： 作為指令關鍵字，確保本條指令不會因編譯器的優化而省略，且要求每次直接讀值.
而 const 是一個C語言的關鍵字，它限定一個變量不允許被改變。
三、在 stm32f10x.h 文件裏，有如下定義：
typedef int32_t s32;
typedef int16_ts16;
typedef int8_t s8;
 
typedef constint32_t sc32;  
typedef constint16_t sc16;  
typedef constint8_t sc8;  
 
typedef __IOint32_t  vs32;
typedef __IOint16_t  vs16;
typedef __IOint8_t   vs8;
 
typedef __Iint32_t vsc32;  
typedef __Iint16_t vsc16;  
typedef __I int8_tvsc8;  
 
typedef uint32_t u32;
typedef uint16_tu16;
typedef uint8_t u8;
 
typedef constuint32_t uc32;  
typedef constuint16_t uc16;  
typedef constuint8_t uc8;  
 
typedef __IOuint32_t  vu32;
typedef __IOuint16_t vu16;
typedef __IOuint8_t  vu8;
 
typedef __Iuint32_t vuc32;  
typedef __Iuint16_t vuc16;  
typedef __I uint8_tvuc8;