Source code for automate.extensions.rpio.rpio_service

# -*- coding: utf-8 -*-
# (c) 2015 Tuomas Airaksinen
# This file is part of automate-rpio.
# automate-rpio is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
# automate-rpio is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# GNU General Public License for more details.
# You should have received a copy of the GNU General Public License
# along with automate-rpio.  If not, see <>.

from __future__ import unicode_literals

from threading import Thread

from traits.api import CBool, Any
from automate.service import AbstractSystemService
import signal

[docs]class RpioService(AbstractSystemService): """ Service that provides interface to Raspberry Pi GPIO via `RPIO library <>`_. """ #: Perform GPIO cleanup when exiting (default: False). gpio_cleanup = CBool(False) #: Use RPIO instead of RPI.GPIO rpio = CBool(False) _gpio_thread = Any _hw = Any def setup(self):"Initializing RpioService (Raspberry Pi GPIO support)") try: if self.rpio: import RPIO import RPIO.PWM else: import RPi.GPIO as RPIO except (ImportError, SystemError, RuntimeError): self.logger.warning('RPIO module could not be imported. Enabling mocked RPIO') self.logger.warning("To use Raspberry Pi GPIO ports (sensors / actuators) please install module RPIO") import mock RPIO = mock.MagicMock() self._hw = RPIO self._hw.setmode(RPIO.BCM) if self.rpio: self._gpio_thread = t = Thread(target=RPIO.wait_for_interrupts, name='RpioService thread') t.daemon = True t.start()"RPIO initialized") def cleanup(self): if self.rpio: self._hw.stop_waiting_for_interrupts() self._hw.cleanup_interrupts() self._gpio_thread.join() if self.gpio_cleanup: self._hw.cleanup() def enable_input_port(self, port, callback, pull_up_down): pud = {"down": self._hw.PUD_DOWN, "up": self._hw.PUD_UP, "none": self._hw.PUD_OFF} if self.rpio: self._hw.setup(port, self._hw.IN) self._hw.add_interrupt_callback(port, callback, edge="both", pull_up_down=pud[pull_up_down]) else: self._hw.setup(port, self._hw.IN, pull_up_down=pud[pull_up_down]) self._hw.add_event_detect(port, self._hw.BOTH, lambda _port: callback(_port, self._hw.input(_port))) def get_input_status(self, port): return self._hw.input(port) def disable_input_port(self, port): if self.rpio: self._hw.del_interrupt_callback(port) else: self._hw.remove_event_detect(port) self._hw.cleanup(port) def enable_output_port(self, port): self._hw.setup(port, self._hw.OUT) def disable_output_port(self, port): self._hw.setup(port, self._hw.IN) def get_pwm_module(self): if not self.rpio: self.logger.error('PWM supported only when rpio attribute in RpioService is enabled') try: self._hw.PWM.setup() signal.signal(signal.SIGCHLD, signal.SIG_IGN) self.logger.warning('SIGCHLD is now ignored totally due to RPIO.PWM bug. Might cause side effects!') except RuntimeError as e: if 'has already been called before' in e.message: pass else: raise return self._hw.PWM def set_output_port_status(self, port, status): self._hw.output(port, status)