fsm_button.h File Reference

Header for fsm_button.c file. More...

#include <stdint.h>
#include <stdbool.h>
#include "fsm.h"

Data Structures
struct	fsm_button_t
	Structure of the Button FSM. More...

Enumerations
enum	FSM_BUTTON {   BUTTON_RELEASED = 0,   BUTTON_RELEASED_WAIT,   BUTTON_PRESSED,   BUTTON_PRESSED_WAIT }
	Enumerator for the button finite state machine. More...

Functions
fsm_button_t *	fsm_button_new (uint32_t debounce_time_ms, uint8_t button_id)
	Create a new button FSM. More...
void	fsm_button_destroy (fsm_button_t *p_fsm)
	Destroy a button FSM. More...
void	fsm_button_fire (fsm_button_t *p_fsm)
	Fire the button FSM. More...
uint32_t	fsm_button_get_duration (fsm_button_t *p_fsm)
	Return the duration of the last button press. More...
void	fsm_button_reset_duration (fsm_button_t *p_fsm)
	Reset the duration of the last button press. More...
uint32_t	fsm_button_get_debounce_time_ms (fsm_button_t *p_fsm)
	Get the debounce time of the button FSM. More...
bool	fsm_button_check_activity (fsm_button_t *p_fsm)
	Check if the button FSM is active, or not. More...

Detailed Description

Header for fsm_button.c file.

Author

Sistemas Digitales II

Date

2026-01-01

Enumeration Type Documentation

FSM_BUTTON

enum FSM_BUTTON

Enumerator for the button finite state machine.

This enumerator defines the different states that the button finite state machine can be in. Each state represents a specific condition or step in the button press process.

Enumerator
BUTTON_RELEASED	Starting state. Also comes here when the button has been released
BUTTON_RELEASED_WAIT	State to perform the anti-debounce mechanism for a falling edge
BUTTON_PRESSED	State while the button is being pressed
BUTTON_PRESSED_WAIT	State to perform the anti-debounce mechanism for a rising edge

Function Documentation

fsm_button_check_activity()

bool fsm_button_check_activity

(

fsm_button_t *

p_fsm

)

Check if the button FSM is active, or not.

The button is inactive when it is in the status BUTTON_RELEASED.

TODO alumnos Version 4:

✅ 1. Get the field current_state of the FSM (field f of the struct).
✅ 2. Return false if the current state is BUTTON_RELEASED. Otherwise, return true.

Parameters

p_fsm

Pointer to an fsm_button_t struct.

Returns

true

false

fsm_button_destroy()

void fsm_button_destroy

(

fsm_button_t *

p_fsm

)

Destroy a button FSM.

This function destroys a button FSM and frees the memory.

Parameters

p_fsm

Pointer to an fsm_button_t struct.

fsm_button_fire()

void fsm_button_fire

(

fsm_button_t *

p_fsm

)

Fire the button FSM.

This function is used to fire the button FSM. It is used to check the transitions and execute the actions of the button FSM.

TODO alumnos:

✅ 1. Call the fsm_fire() function. Pass the address of the fsm_t struct.

Parameters

p_fsm

Pointer to an fsm_button_t struct.

fsm_button_get_debounce_time_ms()

uint32_t fsm_button_get_debounce_time_ms

(

fsm_button_t *

p_fsm

)

Get the debounce time of the button FSM.

This function returns the debounce time of the button FSM.

TODO alumnos:

✅ 1. Retrieve and return the field debounce_time_ms

Parameters

p_fsm

Pointer to an fsm_button_t struct.

Returns

uint32_t Debounce time in milliseconds.

fsm_button_get_duration()

uint32_t fsm_button_get_duration

(

fsm_button_t *

p_fsm

)

Return the duration of the last button press.

TODO alumnos:

✅ 1. Retrieve and return the field duration

Parameters

p_fsm

Pointer to an fsm_button_t struct.

Returns

uint32_t Duration of the last button press in milliseconds.

fsm_button_new()

fsm_button_t* fsm_button_new	(	uint32_t	debounce_time_ms,
		uint8_t	button_id
	)

Create a new button FSM.

This function creates a new button FSM with the given debounce time and button ID.

Parameters

debounce_time_ms	Debounce time in milliseconds.
button_id	Button ID. Must be unique.

Returns

fsm_button_t* Pointer to the button FSM.

fsm_button_reset_duration()

void fsm_button_reset_duration

(

fsm_button_t *

p_fsm

)

Reset the duration of the last button press.

TODO alumnos:

✅ 1. Set to 0 the field duration

Parameters

p_fsm

Pointer to an fsm_button_t struct.