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案例陈述中的数组

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我在使用数组作为状态机的case语句时遇到麻烦。大多数站点都提到数组不能用于case语句，因此我一直在尝试解决该问题，但到目前为止它没有成功。我真的很感谢任何帮助或建议。 为澄清起见：我不想对状态进行硬编码，我试图以这样的方式制作程序：如果用户仅更改fsm_state_array []中的顺序，程序将在其中执行仅在不更改void loop（）中其他任何东西的情况下排序。

这是到目前为止我尝试过的工作，当用户在数组中输入状态序列时，我已经使用函数对功能进行了硬编码以检查先前状态，当前状态和下一个状态，因此在我的代码中，状态应该变为从0-> 2-> 3-> 1开始，但是，我得到0-> 2-> 1->3。我知道如果只使用数组，这个问题就可以轻松解决。语句，但编译器给我一个错误。我真的很感谢任何帮助或建议。

我的代码如下所示：

//Objectives: Use input from laser to control pre-amp on adc. Multiplex the inputs on Pre-Amp
//Type: Pulse,Freq:20Hz (50ms),Amp:5.0 Vpp,Offset:500mV,Width = 100ns

//-----------------------PROJECT libraRIES----------------------------------
#include <Bounce2.h>
#include <Arduino.h>
#include <avr/io.h>
#include <avr/wdt.h>
#include <avr/interrupt.h>
//-----------------------DEFInes------------------------------------------
//Declare Laser Input Pin
#define LASER_PIN 2

//Declare Reset Pin
#define RESET_PIN 3


typedef enum {
  STATE_0,STATE_1,STATE_2,STATE_3
} fsm_state;

//User can change or remove states here
fsm_state fsm_state_Array[] = {STATE_0,STATE_3,STATE_1};

 //*eNextstate controls on which state the program starts the state machine,default is STATE_00,Must be same value as Transition_State[0]
fsm_state eNextState = fsm_state_Array[0];

int Current_State = 0;
int Next_State = 0;
int Previous_State = 0;

// -------------------------CONSTANTS (won't change)-------------------------------------
const unsigned long period = 1000;  //the value is a number of milliseconds

//-------------------------VARIABLES (will change)-------------------------------------
bool only_for_print = false;//used only for print state ments

int reset_switch = 1;//Start HIGH to avoid reset
int PulseCount = 0; //Pulse count from X-RAY
int Output = 0;//Switch state on the Pre-Amp
int wait = 0;//wait for pulses count
int N = 20;//no. of pulses to count before switching states
volatile int IRQcount = 0;
volatile boolean reset_flag = false;

unsigned long start_time = 0;
unsigned long current_time = 0;

//----------------------------USER DEFINED FUNCTIONS---------------------------------
void fsm();
void loop();
void setup();
void WDT_RESET();
void IRQcounter();
void CountPulses();
//-----------------------------DEBOUNCE FUNCTIONS---------------------------------------


//--------------------------------MAIN SETUP--------------------------------------

void setup()
{

  Serial.begin(115200);
  //Pin Setup
  pinmode(LASER_PIN,INPUT_PULLUP);
  pinmode(RESET_PIN,INPUT_PULLUP);
  attachInterrupt(digitalPinToInterrupt(LASER_PIN),IRQcounter,RISING);//attach interrupt handler to laser input
  attachInterrupt (digitalPinToInterrupt (RESET_PIN),RESET_ISR,FALLING);  // attach interrupt handler to reset,wait for user press button or switch
  start_time = millis();   //initial start time
  sei();//Turn on Interrupts

  WaitForPulses();//Waits to detect 20 pulses
}

//--------------------------------MAIN LOOP----------------------------------
void loop()
{


  current_time = millis();
  fsm();//State machine
}


//--------------------------------PULSE COUNT FUNCTION--------------------------------------------



void CountPulses()
{
  //  current_time = millis();
  if ((current_time - start_time) >= period)
  {
    start_time = current_time;
    cli();//disable interrupts
    PulseCount = IRQcount;
    IRQcount = 0;
    Serial.print(F("Pulse Count is = "));
    Serial.println(PulseCount);
    sei();//enable interrupts
  }
}

//--------------------------------STATE MACHINE FUNCTION--------------------------------------------
void fsm()
{
  switch (eNextState)
  {



    case STATE_0:

      /////////Print Statement only for debugging//////////
      while (only_for_print == false)
      {
        Serial.println("The state is 0");
        only_for_print = true;
      }  

      ///////// Count Pulses Setup /////////////////
        Previous_State = fsm_state_Array[3];
        Current_State= 0;
        Next_State = fsm_state_Array[1];


        current_time = millis();
        CountPulses();
        Output = 0;

      if (PulseCount == N)
      {
        PulseCount = 0;//Reset Pulse Count
        only_for_print = false; //used only for print statments
       State_Check_0_to_1();//Move to next state
      }
      break;


    case STATE_1:
      /////////Print Statement only for debugging//////////
      while (only_for_print == false)
      {
        Serial.println("The state is 1");
        only_for_print = true;
      }

      ///////// Count Pulses Setup /////////////////

       Previous_State = fsm_state_Array[0];
        Current_State= 1;
        Next_State = fsm_state_Array[2];

      current_time = millis();
      CountPulses();
      Output = 1;
      if (PulseCount == N)
      {
        PulseCount = 0;//Reset Pulse Count
        only_for_print = false; //used only for print statments
        State_Check_1_to_2();//Move to next state
      }
      break;


    case STATE_2:
      /////////Print Statement only for debugging//////////
      while (only_for_print == false)
      {
        Serial.println("The state is 2");
        only_for_print = true;
      }

      ///////// Count Pulses Setup /////////////////

         Previous_State = fsm_state_Array[1];
        Current_State= 2;
        Next_State = fsm_state_Array[3];


      current_time = millis();
      CountPulses();
      Output = 2;
      if (PulseCount == N)
      {
        PulseCount = 0;//Reset Pulse Count
        only_for_print = false; //used only for print statments
        State_Check_2_to_3();//Move to next state
      }

      break;


    case STATE_3:
      /////////Print Statement only for debugging//////////
      while (only_for_print == false)
      {
        Serial.println("The state is 3");
        only_for_print = true;
      }
      ///////// Count Pulses Setup /////////////////

       Previous_State = fsm_state_Array[2];
       Current_State= 3;
       Next_State = fsm_state_Array[0];

      current_time = millis();
      CountPulses();
      Output = 3;
      if (PulseCount == N)
      {
        PulseCount = 0;//Reset Pulse Count
        only_for_print = false; //used only for print statments
       State_Check_3_to_0();//Move to next state
      }

      break;


  }

}

//----------------------------------RESET SWITCH ISR-------------------------------------

void RESET_ISR()
{
  reset_flag = true;
  if (reset_flag == true)
  {
    // Serial.println("System will now Reset");// Only for debugging
    reset_flag = false;//Reset reset switch flag
    wdt_enable(WDTO_500MS);//Reset after 0.5 seconds
    while (1)
    {
      // wdt_reset();          // uncomment to avoid reboot
    }
  }
}


//-----------------------PULSE COUNT ISR---------------------------------------

void IRQcounter()
{
  IRQcount++;
}
//-----------------------WAIT FOR PULSES---------------------------------------
void WaitForPulses()
{
  while (wait < 20)
  {
    if (bit_is_set(EIFR,INTF0))
    {
      Serial.println("Pulse is detected ");
      wait++;
    }
  }
  wait = 0;//reset
}

void State_Check_0_to_1()//Check values of state 0 before going to state 1 
{

    if(Previous_State == fsm_state_Array[3] && Current_State == 0 && Next_State == fsm_state_Array[1])
    {
      eNextState = Next_State;
    }


}

void State_Check_1_to_2()//Check values of state 1 before going to state 2 
{

    if((Previous_State == fsm_state_Array[0]) && (Current_State == 1) && (Next_State == fsm_state_Array[2]))
    {
      eNextState = Next_State;

    }

}


void State_Check_2_to_3()//Check values of state 2 before going to state 3 
{

    if((Previous_State == fsm_state_Array[1]) && (Current_State == 2) && (Next_State == fsm_state_Array[3]))
    {
      eNextState = Next_State;

    }

}


void State_Check_3_to_0()//Check values of state 3 before going to state 0 
{

    if((Previous_State == fsm_state_Array[2]) && (Current_State == 3) && (Next_State == fsm_state_Array[0]))
    {
      eNextState = Next_State;

    }

}

这是我的串行监视器显示的内容：

Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
Pulse is detected
The state is 0                               -----> State 0
Pulse Count is = 72
Pulse Count is = 19
Pulse Count is = 20
The state is 2                               -----> State 2
Pulse Count is = 20
The state is 1                               -----> State 1
Pulse Count is = 21
Pulse Count is = 19
Pulse Count is = 21
Pulse Count is = 19
Pulse Count is = 21
Pulse Count is = 19
Pulse Count is = 21
Pulse Count is = 19
Pulse Count is = 21
Pulse Count is = 20
The state is 3                           -----> State 3
Pulse Count is = 20
The state is 0       
Pulse Count is = 20
The state is 2
Pulse Count is = 20
The state is 1
Pulse Count is = 20
The state is 3

使用注释中建议的带有指针的FSM进行单独测试：

typedef void (*current_state)();
void state0();
void state1();
void state2();
void state3();
current_state states[4]={&state0,&state2,&state3,&state1};
current_state next_state;
void setup() 
{
 Serial.begin(115200);

}

void loop()
{
  current_state();
}


void state0() 
{
   next_state = states[1]; // No parenthesis!
   Serial.println("I am in STATE 0");
}
void state1() 
{
   next_state = states[2]; // No parenthesis!
   Serial.println("I am in STATE 1");
}
void state2() 
{
   next_state = states[3]; // No parenthesis!
   Serial.println("I am in STATE 2");
}
void state3() 
{
   next_state = states[0]; // No parenthesis!
   Serial.println("I am in STATE 3");
}
zhaoyuan6677 回答：案例陈述中的数组

此代码来自STATE_2

的处理 
Next_State = fsm_state_Array[3];

将Next_State设置为STATE_1，因为该数组被初始化为

fsm_state fsm_state_Array[] = {STATE_0,STATE_2,STATE_3,STATE_1};

这意味着... 

fsm_state_Array[0] = STATE_0;
fsm_state_Array[1] = STATE_2;
fsm_state_Array[2] = STATE_3;
fsm_state_Array[3] = STATE_1;  // This is the element used

要提供更“动态”的解决方案，可能比使用开关更好地使用状态的函数指针：

// Current state is just a apointer to a void function
// accepting no parameters
void (*current_state)();

// All states are just void functions accepting no parameters
void state1();
void state2();
...

// To set what is the next state you update current_state
void state1() {
   ...
   current_state = state2; // No parenthesis!
}


// In the main handler you just call current_state

...
current_state(); // Do the state processing

如果要执行一系列操作，则可以使用函数指针保留它们的数组并对其进行迭代：

void (*states[])() = {
    state1,state2,state3,...
    NULL       /// To mark the end of the sequence
};

然后您可以按顺序执行以下步骤

void main() {
    for(int i=0; states[i]; i++) {
        states[i](); // Execute the step
    }
}
arduinoc++optimizationperformanceswitch-statement
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