Macros to create a finite state machine in Arduino

Create a finite state machine in 8 steps

1. Include efsm.h
2. Define states
3. Define inital state
4. Define events
5. Define transitions
6. Define executions
7. Define triggers
8. Enjoy you fsm!

efsm define C Macros to make easy create a fsm.

#include <efsm.h>

STATES {start, step1, step2, finish};

Is translate to:

enum States{start, step1, step2, finish};

INIT(start);

Is translate to:

enum States state = start;

EVENTS {next, back, end};

Is translate to:

enum Events{next, back, end};

Transitions define changes in state when an event is launched:

TRANSITION(event,initalState,finalState,function())

if(event && state == initalState){
state = finalState;
call function();
}

START_TRANSITIONS

TRANSITION(next,start,step1,printf("next\n"))//execute a function
TRANSITION(next,step1,step2,)//no execute function

END_TRANSITIONS

Executions define funtions to call in each state

EXECUTION(executionState,function())

if(state == executionState){ function(); }

START_EXECUTIONS  

EXECUTION(start,printf("start\n"))  
EXECUTION(step1,printf("step1\n"))  

END_EXECUTIONS  

It is not mandatory to use EXECUTIONS

Define conditions to launch events

There are 3 types:

COUNTER(initalState,number,event);

In pseudocode:

if(state == intialState && timesTriggerIsCalledSinLastEvent >= number){
launchEvent(event);
}

TIMER(initalState,milliseconds,event);

In pseudocode:

if(state == intialState && millisecondsSinceLastEvent >= milliseconds){
launchEvent(event);
}

CONDITIONAL(initalState,condition,event);

In pseudocode:

if(state == intialState && condition){
launchEvent(event);
}

START_TRIGGERS

COUNTER(start,5,next); //State start wait 5 iterations and launch event next  
TIMER(step1,2000,next); //State step1 wait 2 sg and launch event next  
CONDITIONAL(start, digitalRead(buttonPin) == HIGH, restart); //State finish wait until push button an launch event restart  

END_TRIGGERS

You need add to loop function:

efsmExecute();
efsmTriggers();

ANY_EVENT
ANY_STATE

Usefull to define events, transactions and triggers

isState(state);

Is true is machine state is state

changeState(state);

Put machine state to state

resetTimer();

Reset time since last event

resetCounter();

Reset counter since last event