STM32F10X.H
1 #include "core_cm3.h" 2 #include "system_stm32f10x.h" 3 #include <stdint.h> 4 5 /** @addtogroup Exported_types 6 * @{ 7 */ 8 9 /*!< STM32F10x Standard Peripheral Library old types (maintained for legacy purpose) */ 10 typedef int32_t s32; 11 typedef int16_t s16; 12 typedef int8_t s8; 13 14 typedef const int32_t sc32; /*!< Read Only */ 15 typedef const int16_t sc16; /*!< Read Only */ 16 typedef const int8_t sc8; /*!< Read Only */ 17 18 typedef __IO int32_t vs32; 19 typedef __IO int16_t vs16; 20 typedef __IO int8_t vs8; 21 22 typedef __I int32_t vsc32; /*!< Read Only */ 23 typedef __I int16_t vsc16; /*!< Read Only */ 24 typedef __I int8_t vsc8; /*!< Read Only */ 25 26 typedef uint32_t u32; 27 typedef uint16_t u16; 28 typedef uint8_t u8; 29 30 typedef const uint32_t uc32; /*!< Read Only */ 31 typedef const uint16_t uc16; /*!< Read Only */ 32 typedef const uint8_t uc8; /*!< Read Only */ 33 34 typedef __IO uint32_t vu32; 35 typedef __IO uint16_t vu16; 36 typedef __IO uint8_t vu8; 37 38 typedef __I uint32_t vuc32; /*!< Read Only */ 39 typedef __I uint16_t vuc16; /*!< Read Only */ 40 typedef __I uint8_t vuc8; /*!< Read Only */ 41 42 typedef enum {RESET = 0, SET = !RESET} FlagStatus, ITStatus; 43 44 typedef enum {DISABLE = 0, ENABLE = !DISABLE} FunctionalState; 45 #define IS_FUNCTIONAL_STATE(STATE) (((STATE) == DISABLE) || ((STATE) == ENABLE)) 46 47 typedef enum {ERROR = 0, SUCCESS = !ERROR} ErrorStatus;
源定义在#include<stdint.h>中
1 /* 2 * 'signed' is redundant below, except for 'signed char' and if 3 * the typedef is used to declare a bitfield. 4 */ 5 6 /* 7.18.1.1 */ 7 8 /* exact-width signed integer types */ 9 typedef signed char int8_t; 10 typedef signed short int int16_t; 11 typedef signed int int32_t; 12 typedef signed __INT64 int64_t; 13 14 /* exact-width unsigned integer types */ 15 typedef unsigned char uint8_t; 16 typedef unsigned short int uint16_t; 17 typedef unsigned int uint32_t; 18 typedef unsigned __INT64 uint64_t; 19 20 /* 7.18.1.2 */ 21 22 /* smallest type of at least n bits */ 23 /* minimum-width signed integer types */ 24 typedef signed char int_least8_t; 25 typedef signed short int int_least16_t; 26 typedef signed int int_least32_t; 27 typedef signed __INT64 int_least64_t; 28 29 /* minimum-width unsigned integer types */ 30 typedef unsigned char uint_least8_t; 31 typedef unsigned short int uint_least16_t; 32 typedef unsigned int uint_least32_t; 33 typedef unsigned __INT64 uint_least64_t; 34 35 /* 7.18.1.3 */ 36 37 /* fastest minimum-width signed integer types */ 38 typedef signed int int_fast8_t; 39 typedef signed int int_fast16_t; 40 typedef signed int int_fast32_t; 41 typedef signed __INT64 int_fast64_t; 42 43 /* fastest minimum-width unsigned integer types */ 44 typedef unsigned int uint_fast8_t; 45 typedef unsigned int uint_fast16_t; 46 typedef unsigned int uint_fast32_t; 47 typedef unsigned __INT64 uint_fast64_t; 48 49 /* 7.18.1.4 integer types capable of holding object pointers */ 50 #if __sizeof_ptr == 8 51 typedef signed __INT64 intptr_t; 52 typedef unsigned __INT64 uintptr_t; 53 #else 54 typedef signed int intptr_t; 55 typedef unsigned int uintptr_t; 56 #endif 57 58 /* 7.18.1.5 greatest-width integer types */ 59 typedef signed __LONGLONG intmax_t; 60 typedef unsigned __LONGLONG uintmax_t;
由上述可知:
1、有符号整型
- s8 占用1个byte,数据范围 -2^7 到 (2^7-1)
- s16 占用2个byte,数据范围 -2^15 到 (2^15-1)
- s32 占用 4个byte,数据范围 -2^31 到 (2^31-1)2^31 = 2147483647
- int64_t占用8个byte,数据范围 -2^63 到 (2^63-1) 2^63 = 9223372036854775807ll
2、无符号整型
- u8 占用1个byte, 数据范围 0 - 2^8
- u16 占用2个byte, 数据范围 0 - 2^16
- u32 占用4个byte, 数据范围 0 - 2^32 2^32 = 4294967295
- uint64_t 占用8个byte, 数据范围 0 - 2^64 2^64 = 18446744073709551615
3、浮点型
- float ——4个byte,有符号型,可以表达负数/小数; Float 类型至少要能精确表示到小数点后6位。
- double——8个byte,有符号型,可以表达负数/小数;Double 类型至少要能精确到小数点后 10 位。
二、不同数据类型混合运算
在C语言中,不同类型的数据间是可以混合运算的。在进行运算时,不同类型的数据要先转换成同一类型,然后进行运算。转换的规则如下:
注意:箭头的方向只表示数据类型级别的高低,由低向高转换,这个转换过程是一步到位的。
(三)数据类型转换规则
各类数据类型的转换,分为两种方式:隐式(编译软件自动完成),显式(程序强制转换)
隐式转换规则:
字符必须先转换为整数(C语言规定字符类型数据和整型数据之间可以通用)
short型转换为int型(同属于整型)
float型数据在运算时一律转换为双精度(double)型,以提高运算精度(同属于实型)
赋值时,一律是右部值转换为左部类型
[注]
当整型数据和双精度数据进行运算时,C先将整型数据转换成双精度型数据,再进行运算,结果为双精度类型数据
当字符型数据和实型数据进行运算时,C先将字符型数据转换成实型数据,然后进行计算,结果为实型数据
显式转换规则:
例:(int)(x+y);
注:强制类型转换时,得到一个所需要的中间变量,原来变量的类型未发生变化。