"""Classes for Motor support."""
from abc import abstractmethod
from enum import Enum
from typing import Type, Union
from j5.components.component import Component, Interface
[docs]class MotorSpecialState(Enum):
"""An enum of the special states that a motor can be set to."""
COAST = 0
BRAKE = 1
MotorState = Union[float, MotorSpecialState]
[docs]class MotorInterface(Interface):
"""An interface containing the methods required to control a motor board."""
[docs] @abstractmethod
def get_motor_state(self, identifier: int) -> MotorState:
"""
Get the current motor state.
:param identifier: identifier of the motor
:returns: state of the motor.
"""
raise NotImplementedError # pragma: no cover
[docs] @abstractmethod
def set_motor_state(self, identifier: int, power: MotorState) -> None:
"""
Set the state of a motor.
:param identifier: identifier of the motor
:param power: state of the motor.
"""
raise NotImplementedError # pragma: no cover
[docs]class Motor(Component):
"""Brushed DC motor output."""
def __init__(
self,
identifier: int,
backend: MotorInterface,
) -> None:
self._backend = backend
self._identifier = identifier
[docs] @staticmethod
def interface_class() -> Type[Interface]:
"""
Get the interface class that is required to use this component.
:returns: interface class.
"""
return MotorInterface
@property
def identifier(self) -> int:
"""
An integer to identify the component on a board.
:returns: component identifier.
"""
return self._identifier
@property
def power(self) -> MotorState:
"""
Get the current power of this output.
:returns: current power of this output.
"""
return self._backend.get_motor_state(self._identifier)
@power.setter
def power(self, new_power: MotorState) -> None:
"""
Set the current state of this output.
:param new_power: state to set the motor to.
:raises ValueError: invalid motor power.
"""
if not isinstance(new_power, MotorSpecialState):
if new_power < -1 or new_power > 1:
raise ValueError("Motor power must be between 1 and -1.")
self._backend.set_motor_state(self._identifier, new_power)