经验累积

使用结构体 C面向对象

例如描述ModbusRTU的协议帧

typedef struct
{
    uint8 device_addr;//从机地址域
    uint8 func_code;//功能码
    uint8 data[];//数据域
    uint8 CRC_L;
    uint8 CRC_H;
}ModbusRTU_Frame;

使用枚举类型 增加代码可读性

替代意义不明的数字，增加代码可读性

//状态机状态枚举
typedef enum
{
    uint8 STATE1 = 1,
    uint8 STATE2,//递增为2
    uint8 STATE3,//递增为3
    uint8 STATE4,//....4
    uint8 STATE5,//....5
}State_Type;

使用映射思想 MAP记录数据

例如，通过ascii值记录出现过的字母,以及出现过的频次

char str[];
int ascii_map[200]={0};

for(int i=0;i<strlen(str);i++)
{
    ascii_map[str[i]]+=1;
}

使用寄存器bit位思想 记录标志位

例如，一个16位的数据类型，uint16。可以使用位操作对16个位赋予1/0状态。用于标记状态位

uint16 FLAG;

for(int i=0;i<16;i++)
{
    if((FLAG>>i)&0x01)
    {
        //action...
    }
    else
    {
        //action...
    }
}

types.h

// Define to prevent recursive inclusion
#ifndef __TYPES_H
#define __TYPES_H

// Files includes
#include <stdint.h>
#include <stdbool.h>



#ifdef __cplusplus
#define     __I     volatile                        ///< Defines 'read only' permissions
#else
#define     __I     volatile const                  ///< Defines 'read only' permissions
#endif
#define     __O     volatile                        ///< Defines 'write only' permissions
#define     __IO    volatile                        ///< Defines 'read / write' permissions


//typedef long long u64;
//typedef long long s64;

typedef int64_t u64;
typedef uint64_t s64;
typedef signed int   s32;
typedef signed short s16;
typedef signed char  s8;

typedef signed int  const  sc32;                    ///< Read Only
typedef signed short const sc16;                    ///< Read Only
typedef signed char  const sc8;                     ///< Read Only

typedef volatile signed int   vs32;
typedef volatile signed short vs16;
typedef volatile signed char  vs8;

typedef volatile signed int  const  vsc32;          ///< Read Only
typedef volatile signed short const vsc16;          ///< Read Only
typedef volatile signed char  const vsc8;           ///< Read Only

typedef unsigned int   u32;
typedef unsigned short u16;
typedef unsigned char  u8;

typedef unsigned int  const  uc32;                  ///< Read Only
typedef unsigned short const uc16;                  ///< Read Only
typedef unsigned char  const uc8;                   ///< Read Only

typedef volatile unsigned int   vu32;
typedef volatile unsigned short vu16;
typedef volatile unsigned char  vu8;

typedef volatile unsigned int  const  vuc32;        ///< Read Only
typedef volatile unsigned short const vuc16;        ///< Read Only
typedef volatile unsigned char  const vuc8;         ///< Read Only
typedef bool    BOOL;
#ifndef NULL
#define NULL ((void *)0)
#endif
typedef enum {RESET = 0, SET = !RESET} FlagStatus, ITStatus;
typedef enum {DISABLE = 0, ENABLE = !DISABLE} FunctionalState;
typedef enum {ERROR = 0, SUCCESS = !ERROR} ErrorStatus;


#define IS_FUNCTIONAL_STATE(STATE) (((STATE) == DISABLE) || ((STATE) == ENABLE))

#define U8_MAX     ((u8)255)
#define S8_MAX     ((s8)127)
#define S8_MIN     ((s8)-128)
#define U16_MAX    ((u16)65535u)
#define S16_MAX    ((s16)32767)
#define S16_MIN    ((s16)-32768)
#define U32_MAX    ((u32)4294967295uL)
#define S32_MAX    ((s32)2147483647)
#define S32_MIN    ((s32)-2147483648uL)

#define MAX(a,b)((a)>(b)?(a):(b))
#define MIN(a,b)((a)<(b)?(a):(b))

#define SET_BIT(reg, bit)     ((reg) |= (bit))
#define CLEAR_BIT(reg, bit)   ((reg) &= ~(bit))
#define READ_BIT(reg, bit)    ((reg) & (bit))
#define CLEAR_REG(reg)        ((reg) = (0x0))
#define WRITE_REG(reg, value)   ((reg) = (value))
#define READ_REG(reg)         ((reg))
#define MODIFY_REG(reg, CLEARMASK, SETMASK)  WRITE_REG((reg), (((READ_REG(reg)) & (~(CLEARMASK))) | (SETMASK)))
#define POSITION_VAL(value)     (__CLZ(__RBIT(value)))

#define LEFT_SHIFT_BIT(x)   (1 << x)


#endif