Límite

Inicializando la clase límite

Un interruptor de límite se crea utilizando el siguiente constructor:

Limit(port)

Este constructor utiliza un parámetro:

Parámetro	Descripción
port	The 3-Wire Port that the Limit Switch is connected to, whether it’s a port on the Brain, or a 3-Wire Expander.

A Brain or 3-Wire Expander must be created first before they can be used to create an object with the Limit Class constructor.

# Create the Brain.
brain = Brain()
# Construct a Limit Switch "limit" with the Limit class.
limit = Limit(brain.three_wire_port.a)

This limit object will be used in all subsequent examples throughout this API documentation when referring to Limit class methods.

Métodos de clase

pressed()

The pressed(callback, arg) method registers a callback function for when the Limit Switch is pressed.

Parámetros	Descripción
callback	La función de devolución de llamada que se llamará cuando se presione el interruptor de límite.
arg	Opcional. Una tupla de argumentos para pasar a la función de devolución de llamada.

Devoluciones: Ninguna.

# Define a function switch_pressed().
def switch_pressed():
    # The Brain will print that the Limit Switch was pressed 
    # on the Brain's screen.
    brain.screen.print("switch pressed")
# Run switch_pressed when the Limit Switch is pressed.
limit.pressed(switch_pressed)

released()

The released(callback, arg) method registers a callback function for when the Limit Switch is released.

Parámetros	Descripción
callback	La función de devolución de llamada que se llamará cuando se libere el interruptor de límite.
arg	Opcional. Una tupla de argumentos para pasar a la función de devolución de llamada.

Devoluciones: Ninguna.

# Define a function switch_released().
def switch_released():
    # The Brain will print that the Limit Switch was released
    # on the Brain's screen.
    brain.screen.print("switch released") 
# Run switch_released when the Limit Switch is released.
limit.released(switch_released)

pressing()

The pressing() method checks if the Limit Switch is currently being pressed.

Returns: True if the Limit Switch is currently being pressed. False if it is not.