Array in Case Statement

Question

У меня проблемы с использованием массива для оператора case для моего конечного автомата. Большинство сайтов упоминают, что массив не может использоваться для операторов case, поэтому я пытался обойти его, но пока он не удался. Буду очень признателен за любую помощь или предложения для этого. Для уточнения : я не хочу жестко кодировать состояния, я пытаюсь сделать программу таким образом, чтобы, если пользователь только изменяет порядок в fsm_state_array [], программа выполнялась в таком порядкетолько без изменения чего-либо еще в цикле void ().

Вот то, что я пробовал до сих пор, я использовал функции для жесткого кода, чтобы проверить предыдущее состояние, текущее состояние и следующее состояние, когда пользователь вводит свою последовательность состояний в массив, поэтому в моем коде нижесостояния должны идти от 0 -> 2 -> 3 -> 1, однако я получаю 0 -> 2 -> 1 -> 3. Я знаю, что эту проблему легко решить, если я просто использую массивв случае утверждения, но компилятор выдает мне ошибку. Я был бы очень признателен за любую помощь или предложения для этого.

Мой код показан ниже:

//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_2, 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;

    }

}

Вот что показывает мой последовательный монитор:

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

Отдельнокод для проверки FSM с указателями, как предлагается в комментариях:

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");
}

Answer 1

Этот код из STATE_2

Next_State = fsm_state_Array[3];

устанавливает Next_State в STATE_1, потому что массив инициализируется как

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

Это означает ...

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

Чтобы обеспечить более «динамическое» решение, возможно, использование указателя функции для состояний лучше, чем использование переключателя:

// 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

Если вы хотите выполнить последовательность операций, тогда используйте указатели на функциивы можете просто сохранить их массив и перебрать его:

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

, затем вы можете выполнить шаги последовательно с

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