C语言映射表在串口数据解析中的应用

来源：物联网IoT威廉希尔官方网站

一、映射表在串口数据解析中的应用

1、数据结构

typedef struct 
{
    char CMD[CMDLen];
    unsigned char (*cmd_operate)(char *data);
}Usart_Tab;

2、指令、函数映射表

static const Usart_Tab InstructionList[CMDMax]=
{
    {"PWON",PowOn},
    {"PWOFF",PowOff},
    {"HDCP",HdcpOnOff},
    {"/V",QueryKaVersion},
    {"EDIDUpgrade",UpdataEDID},
    {"Psave",Psave},
    {"Precall",Precall},
    {"Pclear",Pclear},
};

3、串口解析函数实现

unsigned char DataAnalysis(char *buf)
{
  unsigned char i,Result;
  char *NEXT=NULL;
  for(i=0;i

二、映射表在UI设计中的应用

1、数据结构

菜单枚举：

typedef enum
{
  stage1=0,
  stage2,
  stage3,
  stage4,
  stage5,
  stage6,
  stage7,
  stage8,
  stage9,
}SCENE;

数据结构：

typedef struct {
  void (*current_operate)(); //当前场景的处理函数
  SCENE Index;               //当前场景的标签
  SCENE Up;                  //按下Up键跳转的场景
  SCENE Down;                //按下Down键跳转的场景
  SCENE Right;               //按下Left键跳转的场景
  SCENE Left;                //按下Right键跳转的场景
}STAGE_TAB;

2、函数映射表

STAGE_TAB stage_tab[]={
  #.    operate       Index    Up     Down    Left   Right   
  {Stage1_Handler,  stage1,  stage4,  stage7,  stage3, stage2},
  {Stage2_Handler,  stage2,  stage5,  stage8,  stage1, stage3},
  {Stage3_Handler,  stage3,  stage6,  stage9,  stage2, stage1},
  {Stage4_Handler,  stage4,  stage7,  stage1,  stage6, stage5},
  {Stage5_Handler,  stage5,  stage8,  stage2, stage4,  stage6},
  {Stage6_Handler,  stage6,  stage9,  stage3, stage5,  stage4},
  {Stage7_Handler,  stage7,  stage1,  stage4, stage9,  stage8},
  {Stage8_Handler,  stage8,  stage2,  stage5, stage7,  stage9},
  {Stage9_Handler,  stage9,  stage3,  stage6, stage8,  stage7},
};

3、定义两个变量保存当前场景和上一个场景

char current_stage=stage1;
char prev_stage=current_stage;

4、按下Up按键 跳转到指定场景current_stage的值根据映射表改变

current_stage =stage_tab[current_stage].Up;

5、场景改变后 根据映射表执行相应的函数Handler

if(current_stage!=prev_stage)
{
  stage_tab[current_stage].current_operate();
  prev_stage=current_stage;
}