Five-Way Button (button)

This module manages the input of 5 buttons. It supports debouncing, short press and long press detection, automatic interrupt handling, and eliminates the need for frequent polling. It lets you register short press and long press callbacks for each button separately.

Button Layout and Hardware Connection

Button Name	GPIO Pin
up	18
down	45
left	46
right	0
center	44

note

All buttons use internal pull-up and are triggered on a low level (active-low press).

Class Definition

1. Button(long_press_threshold=1000, debounce_time=50)

Function: Initialize the button manager and start listening for all button inputs.

Arguments:

Argument	Type	Description	Default
long_press_threshold	int	Long press threshold (ms)	1000
debounce_time	int	Debounce time (ms)	50

Example:

from button import Button

buttons = Button(long_press_threshold=800, debounce_time=30)

2. register_callback(button_name, press_type, callback)

Function: Register a short press or long press callback for a specified button.

Arguments:

Argument	Type	Description
button_name	str	Button name: 'up', 'down', 'left', 'right', 'center'
press_type	str	Event type: 'short' (short press), 'long' (long press)
callback	function	Callback function (no arguments)

Example:

def on_center_short():
    print("center short pressed")

def on_left_long():
    print("left long pressed")

buttons.register_callback('center', 'short', on_center_short)
buttons.register_callback('left', 'long', on_left_long)

3. get_button_state(button_name) -> bool

Function: Query whether the specified button is currently pressed.

Return value:

• True: pressed
• False: not pressed
• None: invalid button name

Example:

if buttons.get_button_state('center'):
    print("center is pressed")

4. deinit()

Function: Release all resources and close interrupts and timers. Call it when button control is no longer needed.

Example:

buttons.deinit()

Workflow

• Uses hardware interrupts (IRQ) to detect button state changes;
• Built-in debounce logic avoids false triggers from button bounce;
• On press, starts a long press timer; when long_press_threshold is reached, triggers the long press event;
• On release, judges the press duration; if it is below the long press threshold, triggers the short press event.

Complete Usage Example

from button import Button
import time

# Initialize the button manager
buttons = Button()

# Register short press events
buttons.register_callback('center', 'short', lambda: print("center short"))
buttons.register_callback('up', 'short', lambda: print("up short"))

# Register long press events
buttons.register_callback('center', 'long', lambda: print("center long"))
buttons.register_callback('down', 'long', lambda: print("down long"))

# Main loop (can run alongside other tasks)
try:
    while True:
        time.sleep(0.1)
except KeyboardInterrupt:
    buttons.deinit()

⚠ Notes

• This module suits embedded real-time control and avoids frequent polling.
• You can register callbacks with lambda or custom functions.
• It is recommended to call deinit() to release hardware resources when the system exits.

Hardware Limitations

• The button logic level is active-low (internal pull-up).
• The number of buttons is fixed at 5, and the GPIOs cannot be customized (unless you change the code).