button.h File Reference

A AVR helper for working with individual buttons. More...

#include <string.h>
#include <stdint.h>
#include <util/atomic.h>
#include <sls-avr/avr.h>

Go to the source code of this file.

Data Structures
struct	btn_info_struct
	Information about a button. More...

Macros
#define	BTN_MAX_SCAN_COUNT   254U
	Limit on the number of cycles for which a press is considered complete.
#define	BTN_LONG_COUNT   40U
	The number that is compared to the counter of inputs to the btn_proc function in the pressed state 2-254. When the set value is reached, the button can receive the long pressed status.
#define	BTN_ALLOW_LONG   0
	Allows long pressed status.
#define	BTN_RESET_UNUSED_COUNT   0
	The number that is compared to the counter of unused click 0-254. When the set value is reached, the btn_info_struct structure is reset to its default state.
#define	BTN_DOWN_COUNT   3U
	The number that is compared to the counter of inputs to the btn_proc function in the pressed state 1-254. When the set value is reached, the button can receive the pressed status.
#define	BTN_UP_COUNT   2U
	The number that is compared to the counter of inputs to the btn_proc function in the unpressed state 0-254. When the set value is reached, the button takes on the triggered status.
#define	BTN_FAST_SOME_CODE   0
	If enabled then in the btn_reset function, instead of resetting, only the processing flag is set.
#define	BTN_INFO_STATE_DEFAULT   0
	Default state value. See btn_info_struct.
#define	BTN_INFO_STRUCT_DEFAULT   {._counter = 0, ._up_counter = 0, .state = BTN_INFO_STATE_DEFAULT}
	Default button information structure btn_info_struct.
#define	btn_is_holded(_state)
	Is button holded.
#define	btn_is_ready(_state)
	Completed but unprocessed click.
#define	btn_is_clicked(_state)
	Tests normal click.
#define	btn_is_long_clicked(_state)
	Tests long click.
#define	btn_set_processed(_state)
	Is the button taken into account.
#define	BTN_ATOMIC_FUNCTIONS   0
	Allow ATOMIC_BLOCK wrappers for button processing.

Typedefs
typedef volatile btn_info_struct	btn_info_t
	Information about a button type. See btn_info_struct.

Functions
static void	btn_reset (btn_info_t *const btn_info)
	Resets the button state to default.
void	btn_proc (btn_info_t *const btn_info, const bool is_now_hold)
	Update counters and button press stages for a button information structure.
static void	btn_reset_atomic (btn_info_t *const btn_info)
	Such as the btn_reset, but executed atomically.
static void	btn_reset_atomic_fegi (btn_info_t *const btn_info)
	Such as the btn_reset, but executed atomically with force enabling ot the global interrupts.
static void	btn_proc_atomic (btn_info_t *const btn_info, const bool is_now_hold)
	Such as the btn_proc, but executed atomically.
static void	btn_proc_atomic_fegi (btn_info_t *const btn_info, const bool is_now_hold)
	Such as the btn_proc, but executed atomically with force enabling ot the global interrupts.
static btn_info_struct	btn_get_info (btn_info_t *const btn_info)
	Actions before events proc.
static btn_info_struct	btn_get_info_fegi (btn_info_t *const btn_info)
	Such as the btn_get_info, but with force enabling ot the global interrupts.

Detailed Description

A AVR helper for working with individual buttons.

Author

Simon Litt simon.nosp@m.@1it.nosp@m.t.net https://coding.1itt.net, https://github.com/SimonLitt

Copyright

GNU General Public License v3.0

#include <sls-avr/avr.h>
...
void init_buttons(void) {
    PIN_TO_READ(BTN_1_PORT, BTN_1_PIN);
    PIN_TO_READ(BTN_2_PORT, BTN_2_PIN);
}
 
void buttons_loop(void) {
    static btn_info_t btn_1_info = BTN_INFO_STRUCT_DEFAULT;
    btn_proc(&btn_1_info, !(PIN_READ(BTN_1_PORT, BTN_1_PIN)));
    if (btn_is_clicked(btn_1_info.state)) {
        on_click1();
        btn_reset(&btn_1_info);
    }
 
    static btn_info_t btn_2_info = BTN_INFO_STRUCT_DEFAULT;
    btn_proc(&btn_2_info, !(PIN_READ(BTN_2_PORT, BTN_2_PIN)));
    if (btn_is_clicked(btn_2_info.state)) {
        on_click2();
        btn_reset(&btn_2_info);
    }
}
...

Macro Definition Documentation

BTN_ALLOW_LONG

#define BTN_ALLOW_LONG   0

Allows long pressed status.

BTN_ATOMIC_FUNCTIONS

#define BTN_ATOMIC_FUNCTIONS   0

Allow ATOMIC_BLOCK wrappers for button processing.

Remarks

Sometimes it's more convenient to handle keystrokes within an interrupt. However, it's not recommended to linger in an interrupt for too long.

BTN_DOWN_COUNT

#define BTN_DOWN_COUNT   3U

The number that is compared to the counter of inputs to the btn_proc function in the pressed state 1-254. When the set value is reached, the button can receive the pressed status.

BTN_FAST_SOME_CODE

#define BTN_FAST_SOME_CODE   0

If enabled then in the btn_reset function, instead of resetting, only the processing flag is set.

Remarks

This allows for the same code to be achieved with the BTN_UP_COUNT macro on and off, but disables re-triggering.

BTN_INFO_STATE_DEFAULT

#define BTN_INFO_STATE_DEFAULT   0

Default state value. See btn_info_struct.

BTN_INFO_STRUCT_DEFAULT

#define BTN_INFO_STRUCT_DEFAULT   {._counter = 0, ._up_counter = 0, .state = BTN_INFO_STATE_DEFAULT}

Default button information structure btn_info_struct.

btn_is_clicked

#define btn_is_clicked

(

_state

)

Value:

(flag_is_set((_state), __BTN_STATE_SHORT_CLICK_BIT))

Tests normal click.

Parameters

_state

Stages of click processing

Returns

Is clicked

btn_is_holded

#define btn_is_holded

(

_state

)

Value:

((_state) & (__BTN_IS_HOLDED))

Is button holded.

Parameters

_state

Stages of click processing

Returns

Is holded

btn_is_long_clicked

#define btn_is_long_clicked

(

_state

)

Tests long click.

Parameters

_state

Stages of click processing

Returns

Is long clicked

btn_is_ready

#define btn_is_ready

(

_state

)

Value:

((_state) & (__BTN_IS_CLICKED))

Completed but unprocessed click.

Parameters

_state

Stages of click processing

Returns

Is clicked

BTN_LONG_COUNT

#define BTN_LONG_COUNT   40U

The number that is compared to the counter of inputs to the btn_proc function in the pressed state 2-254. When the set value is reached, the button can receive the long pressed status.

BTN_MAX_SCAN_COUNT

#define BTN_MAX_SCAN_COUNT   254U

Limit on the number of cycles for which a press is considered complete.

BTN_RESET_UNUSED_COUNT

#define BTN_RESET_UNUSED_COUNT   0

The number that is compared to the counter of unused click 0-254. When the set value is reached, the btn_info_struct structure is reset to its default state.

btn_set_processed

#define btn_set_processed

(

_state

)

Value:

((_state) = ((_state) & ~(__BTN_IS_CLICKED)) | _BTN_STAGE_PROCESSED)

Is the button taken into account.

It is necessary so that when released, the status does not change to clicked. Used when the button can be a macro button(function modifier).

Parameters

_state

Stages of click processing

BTN_UP_COUNT

#define BTN_UP_COUNT   2U

The number that is compared to the counter of inputs to the btn_proc function in the unpressed state 0-254. When the set value is reached, the button takes on the triggered status.

Remarks

If the value is O then the click is considered to have been counted even before the button is released. In this case, resetting the state will lead to a re-trigger, if this is undesirable, it needs to set the processing flag see btn_set_processed.

Typedef Documentation

btn_info_t

typedef volatile btn_info_struct btn_info_t

Information about a button type. See btn_info_struct.

Function Documentation

btn_get_info()

static btn_info_struct btn_get_info ( btn_info_t *const btn_info )

inlinestatic

Actions before events proc.

Parameters

[out]

btn_info

Information about a button.

Returns

Currently copy of btn_info_struct

btn_get_info_fegi()

static btn_info_struct btn_get_info_fegi ( btn_info_t *const btn_info )

inlinestatic

Such as the btn_get_info, but with force enabling ot the global interrupts.

Parameters

[out]

btn_info

Information about a button.

btn_proc()

void btn_proc	(	btn_info_t *const	btn_info,
		const bool	is_now_hold )

Update counters and button press stages for a button information structure.

If not called from an interrupt, or if other interrupts are enabled in the interrupt, then it should be executed atomically.

Parameters

[out]	btn_info	Information about a button.
[in]	is_now_hold	Is the button currently pressed?

btn_proc_atomic()

static void btn_proc_atomic ( btn_info_t *const btn_info, const bool is_now_hold )

inlinestatic

Such as the btn_proc, but executed atomically.

Parameters

[out]	btn_info	Information about a button.
[in]	is_now_hold	Is the button currently pressed?

btn_proc_atomic_fegi()

static void btn_proc_atomic_fegi ( btn_info_t *const btn_info, const bool is_now_hold )

inlinestatic

Such as the btn_proc, but executed atomically with force enabling ot the global interrupts.

Parameters

[out]	btn_info	Information about a button.
[in]	is_now_hold	Is the button currently pressed?

btn_reset()

static void btn_reset ( btn_info_t *const btn_info )

inlinestatic

Resets the button state to default.

Parameters

[out]

btn_info

Information about a button.

btn_reset_atomic()

static void btn_reset_atomic ( btn_info_t *const btn_info )

inlinestatic

Such as the btn_reset, but executed atomically.

Parameters

[out]

btn_info

Information about a button.

btn_reset_atomic_fegi()

static void btn_reset_atomic_fegi ( btn_info_t *const btn_info )

inlinestatic

Such as the btn_reset, but executed atomically with force enabling ot the global interrupts.

Parameters

[out]

btn_info

Information about a button.