from __future__ import (
unicode_literals,
absolute_import,
print_function,
division,
)
str = type('')
import os
import pigpio
from . import SPI
from .pi import PiPin, PiFactory, SPI_HARDWARE_PINS
from .data import pi_info
from ..devices import Device
from ..mixins import SharedMixin
from ..exc import (
PinInvalidFunction,
PinSetInput,
PinFixedPull,
PinInvalidPull,
PinInvalidBounce,
PinInvalidState,
SPIBadArgs,
SPIInvalidClockMode,
)
[docs]class PiGPIOFactory(PiFactory):
"""
Uses the `pigpio`_ library to interface to the Pi's GPIO pins. The pigpio
library relies on a daemon (``pigpiod``) to be running as root to provide
access to the GPIO pins, and communicates with this daemon over a network
socket.
While this does mean only the daemon itself should control the pins, the
architecture does have several advantages:
* Pins can be remote controlled from another machine (the other
machine doesn't even have to be a Raspberry Pi; it simply needs the
`pigpio`_ client library installed on it)
* The daemon supports hardware PWM via the DMA controller
* Your script itself doesn't require root privileges; it just needs to
be able to communicate with the daemon
You can construct pigpio pins manually like so::
from gpiozero.pins.pigpio import PiGPIOFactory
from gpiozero import LED
factory = PiGPIOFactory()
led = LED(12, pin_factory=factory)
This is particularly useful for controlling pins on a remote machine. To
accomplish this simply specify the host (and optionally port) when
constructing the pin::
from gpiozero.pins.pigpio import PiGPIOFactory
from gpiozero import LED
factory = PiGPIOFactory(host='192.168.0.2')
led = LED(12, pin_factory=factory)
.. note::
In some circumstances, especially when playing with PWM, it does appear
to be possible to get the daemon into "unusual" states. We would be
most interested to hear any bug reports relating to this (it may be a
bug in our pin implementation). A workaround for now is simply to
restart the ``pigpiod`` daemon.
.. _pigpio: http://abyz.co.uk/rpi/pigpio/
"""
def __init__(
self, host=os.getenv('PIGPIO_ADDR', 'localhost'),
port=int(os.getenv('PIGPIO_PORT', 8888))):
super(PiGPIOFactory, self).__init__()
self.pin_class = PiGPIOPin
self.spi_classes = {
('hardware', 'exclusive'): PiGPIOHardwareSPI,
('hardware', 'shared'): PiGPIOHardwareSPIShared,
('software', 'exclusive'): PiGPIOSoftwareSPI,
('software', 'shared'): PiGPIOSoftwareSPIShared,
}
self._connection = pigpio.pi(host, port)
# Annoyingly, pigpio doesn't raise an exception when it fails to make a
# connection; it returns a valid (but disconnected) pi object
if self.connection is None:
raise IOError('failed to connect to %s:%s' % (host, port))
self._host = host
self._port = port
self._spis = []
def close(self):
super(PiGPIOFactory, self).close()
# We *have* to keep track of SPI interfaces constructed with pigpio;
# if we fail to close them they prevent future interfaces from using
# the same pins
if self.connection:
while self._spis:
self._spis[0].close()
self.connection.stop()
self._connection = None
@property
def connection(self):
# If we're shutting down, the connection may have disconnected itself
# already. Unfortunately, the connection's "connected" property is
# rather buggy - disconnecting doesn't set it to False! So we're
# naughty and check an internal variable instead...
try:
if self._connection.sl.s is not None:
return self._connection
except AttributeError:
pass
@property
def host(self):
return self._host
@property
def port(self):
return self._port
def _get_revision(self):
return self.connection.get_hardware_revision()
def spi(self, **spi_args):
intf = super(PiGPIOFactory, self).spi(**spi_args)
self._spis.append(intf)
return intf
[docs]class PiGPIOPin(PiPin):
"""
Pin implementation for the `pigpio`_ library. See :class:`PiGPIOFactory`
for more information.
.. _pigpio: http://abyz.co.uk/rpi/pigpio/
"""
_CONNECTIONS = {} # maps (host, port) to (connection, pi_info)
GPIO_FUNCTIONS = {
'input': pigpio.INPUT,
'output': pigpio.OUTPUT,
'alt0': pigpio.ALT0,
'alt1': pigpio.ALT1,
'alt2': pigpio.ALT2,
'alt3': pigpio.ALT3,
'alt4': pigpio.ALT4,
'alt5': pigpio.ALT5,
}
GPIO_PULL_UPS = {
'up': pigpio.PUD_UP,
'down': pigpio.PUD_DOWN,
'floating': pigpio.PUD_OFF,
}
GPIO_EDGES = {
'both': pigpio.EITHER_EDGE,
'rising': pigpio.RISING_EDGE,
'falling': pigpio.FALLING_EDGE,
}
GPIO_FUNCTION_NAMES = {v: k for (k, v) in GPIO_FUNCTIONS.items()}
GPIO_PULL_UP_NAMES = {v: k for (k, v) in GPIO_PULL_UPS.items()}
GPIO_EDGES_NAMES = {v: k for (k, v) in GPIO_EDGES.items()}
def __init__(self, factory, number):
super(PiGPIOPin, self).__init__(factory, number)
self._pull = 'up' if self.factory.pi_info.pulled_up(repr(self)) else 'floating'
self._pwm = False
self._bounce = None
self._callback = None
self._edges = pigpio.EITHER_EDGE
try:
self.factory.connection.set_mode(self.number, pigpio.INPUT)
except pigpio.error as e:
raise ValueError(e)
self.factory.connection.set_pull_up_down(self.number, self.GPIO_PULL_UPS[self._pull])
self.factory.connection.set_glitch_filter(self.number, 0)
def close(self):
if self.factory.connection:
self.frequency = None
self.when_changed = None
self.function = 'input'
self.pull = 'up' if self.factory.pi_info.pulled_up(repr(self)) else 'floating'
def _get_function(self):
return self.GPIO_FUNCTION_NAMES[self.factory.connection.get_mode(self.number)]
def _set_function(self, value):
if value != 'input':
self._pull = 'floating'
try:
self.factory.connection.set_mode(self.number, self.GPIO_FUNCTIONS[value])
except KeyError:
raise PinInvalidFunction('invalid function "%s" for pin %r' % (value, self))
def _get_state(self):
if self._pwm:
return (
self.factory.connection.get_PWM_dutycycle(self.number) /
self.factory.connection.get_PWM_range(self.number)
)
else:
return bool(self.factory.connection.read(self.number))
def _set_state(self, value):
if self._pwm:
try:
value = int(value * self.factory.connection.get_PWM_range(self.number))
if value != self.factory.connection.get_PWM_dutycycle(self.number):
self.factory.connection.set_PWM_dutycycle(self.number, value)
except pigpio.error:
raise PinInvalidState('invalid state "%s" for pin %r' % (value, self))
elif self.function == 'input':
raise PinSetInput('cannot set state of pin %r' % self)
else:
# write forces pin to OUTPUT, hence the check above
self.factory.connection.write(self.number, bool(value))
def _get_pull(self):
return self._pull
def _set_pull(self, value):
if self.function != 'input':
raise PinFixedPull('cannot set pull on non-input pin %r' % self)
if value != 'up' and self.factory.pi_info.pulled_up(repr(self)):
raise PinFixedPull('%r has a physical pull-up resistor' % self)
try:
self.factory.connection.set_pull_up_down(self.number, self.GPIO_PULL_UPS[value])
self._pull = value
except KeyError:
raise PinInvalidPull('invalid pull "%s" for pin %r' % (value, self))
def _get_frequency(self):
if self._pwm:
return self.factory.connection.get_PWM_frequency(self.number)
return None
def _set_frequency(self, value):
if not self._pwm and value is not None:
if self.function != 'output':
raise PinPWMFixedValue('cannot start PWM on pin %r' % self)
# NOTE: the pin's state *must* be set to zero; if it's currently
# high, starting PWM and setting a 0 duty-cycle *doesn't* bring
# the pin low; it stays high!
self.factory.connection.write(self.number, 0)
self.factory.connection.set_PWM_frequency(self.number, value)
self.factory.connection.set_PWM_range(self.number, 10000)
self.factory.connection.set_PWM_dutycycle(self.number, 0)
self._pwm = True
elif self._pwm and value is not None:
if value != self.factory.connection.get_PWM_frequency(self.number):
self.factory.connection.set_PWM_frequency(self.number, value)
self.factory.connection.set_PWM_range(self.number, 10000)
elif self._pwm and value is None:
self.factory.connection.write(self.number, 0)
self._pwm = False
def _get_bounce(self):
return None if not self._bounce else self._bounce / 1000000
def _set_bounce(self, value):
if value is None:
value = 0
elif value < 0:
raise PinInvalidBounce('bounce must be 0 or greater')
self.factory.connection.set_glitch_filter(self.number, int(value * 1000000))
def _get_edges(self):
return self.GPIO_EDGES_NAMES[self._edges]
def _set_edges(self, value):
f = self.when_changed
self.when_changed = None
try:
self._edges = self.GPIO_EDGES[value]
finally:
self.when_changed = f
def _call_when_changed(self, gpio, level, tick):
super(PiGPIOPin, self)._call_when_changed()
def _enable_event_detect(self):
self._callback = self.factory.connection.callback(
self.number, self._edges, self._call_when_changed)
def _disable_event_detect(self):
if self._callback is not None:
self._callback.cancel()
self._callback = None
class PiGPIOHardwareSPI(SPI, Device):
"""
Hardware SPI implementation for the `pigpio`_ library. Uses the ``spi_*``
functions from the pigpio API.
.. _pigpio: http://abyz.co.uk/rpi/pigpio/
"""
def __init__(self, factory, port, device):
self._port = port
self._device = device
self._factory = factory
self._handle = None
super(PiGPIOHardwareSPI, self).__init__()
pins = SPI_HARDWARE_PINS[port]
self._factory.reserve_pins(
self,
pins['clock'],
pins['mosi'],
pins['miso'],
pins['select'][device]
)
self._spi_flags = 8 << 16
self._baud = 500000
self._handle = self._factory.connection.spi_open(
device, self._baud, self._spi_flags)
def _conflicts_with(self, other):
return not (
isinstance(other, PiGPIOHardwareSPI) and
(self._port, self._device) != (other._port, other._device)
)
def close(self):
try:
self._factory._spis.remove(self)
except (ReferenceError, ValueError):
# If the factory has died already or we're not present in its
# internal list, ignore the error
pass
if not self.closed:
self._factory.connection.spi_close(self._handle)
self._handle = None
self._factory.release_all(self)
super(PiGPIOHardwareSPI, self).close()
@property
def closed(self):
return self._handle is None or self._factory.connection is None
@property
def factory(self):
return self._factory
def __repr__(self):
try:
self._check_open()
return 'SPI(port=%d, device=%d)' % (self._port, self._device)
except DeviceClosed:
return 'SPI(closed)'
def _get_clock_mode(self):
return self._spi_flags & 0x3
def _set_clock_mode(self, value):
self._check_open()
if not 0 <= value < 4:
raise SPIInvalidClockMode("%d is not a valid SPI clock mode" % value)
self._factory.connection.spi_close(self._handle)
self._spi_flags = (self._spi_flags & ~0x3) | value
self._handle = self._factory.connection.spi_open(
self._device, self._baud, self._spi_flags)
def _get_select_high(self):
return bool((self._spi_flags >> (2 + self._device)) & 0x1)
def _set_select_high(self, value):
self._check_open()
self._factory.connection.spi_close(self._handle)
self._spi_flags = (self._spi_flags & ~0x1c) | (bool(value) << (2 + self._device))
self._handle = self._factory.connection.spi_open(
self._device, self._baud, self._spi_flags)
def _get_bits_per_word(self):
return (self._spi_flags >> 16) & 0x3f
def _set_bits_per_word(self, value):
self._check_open()
self._factory.connection.spi_close(self._handle)
self._spi_flags = (self._spi_flags & ~0x3f0000) | ((value & 0x3f) << 16)
self._handle = self._factory.connection.spi_open(
self._device, self._baud, self._spi_flags)
def transfer(self, data):
self._check_open()
count, data = self._factory.connection.spi_xfer(self._handle, data)
if count < 0:
raise IOError('SPI transfer error %d' % count)
# Convert returned bytearray to list of ints. XXX Not sure how non-byte
# sized words (aux intf only) are returned ... padded to 16/32-bits?
return [int(b) for b in data]
class PiGPIOSoftwareSPI(SPI, Device):
"""
Software SPI implementation for the `pigpio`_ library. Uses the ``bb_spi_*``
functions from the pigpio API.
.. _pigpio: http://abyz.co.uk/rpi/pigpio/
"""
def __init__(self, factory, clock_pin, mosi_pin, miso_pin, select_pin):
self._closed = True
self._select_pin = select_pin
self._clock_pin = clock_pin
self._mosi_pin = mosi_pin
self._miso_pin = miso_pin
self._factory = factory
super(PiGPIOSoftwareSPI, self).__init__()
self._factory.reserve_pins(
self,
clock_pin,
mosi_pin,
miso_pin,
select_pin,
)
self._spi_flags = 0
self._baud = 100000
try:
self._factory.connection.bb_spi_open(
select_pin, miso_pin, mosi_pin, clock_pin,
self._baud, self._spi_flags)
# Only set after opening bb_spi; if that fails then close() will
# also fail if bb_spi_close is attempted on an un-open interface
self._closed = False
except:
self.close()
raise
def _conflicts_with(self, other):
return not (
isinstance(other, PiGPIOSoftwareSPI) and
(self._select_pin) != (other._select_pin)
)
def close(self):
try:
self._factory._spis.remove(self)
except (ReferenceError, ValueError):
# If the factory has died already or we're not present in its
# internal list, ignore the error
pass
if not self.closed:
self._closed = True
self._factory.connection.bb_spi_close(self._select_pin)
self.factory.release_all(self)
super(PiGPIOSoftwareSPI, self).close()
@property
def closed(self):
return self._closed
def __repr__(self):
try:
self._check_open()
return (
'SPI(clock_pin=%d, mosi_pin=%d, miso_pin=%d, select_pin=%d)' % (
self._clock_pin, self._mosi_pin, self._miso_pin, self._select_pin
))
except DeviceClosed:
return 'SPI(closed)'
def _spi_flags(self):
return (
self._mode << 0 |
self._select_high << 2 |
self._lsb_first << 14 |
self._lsb_first << 15
)
def _get_clock_mode(self):
return self._spi_flags & 0x3
def _set_clock_mode(self, value):
self._check_open()
if not 0 <= value < 4:
raise SPIInvalidClockmode("%d is not a valid SPI clock mode" % value)
self._factory.connection.bb_spi_close(self._select_pin)
self._spi_flags = (self._spi_flags & ~0x3) | value
self._factory.connection.bb_spi_open(
self._select_pin, self._miso_pin, self._mosi_pin, self._clock_pin,
self._baud, self._spi_flags)
def _get_select_high(self):
return bool(self._spi_flags & 0x4)
def _set_select_high(self, value):
self._check_open()
self._factory.connection.bb_spi_close(self._select_pin)
self._spi_flags = (self._spi_flags & ~0x4) | (bool(value) << 2)
self._factory.connection.bb_spi_open(
self._select_pin, self._miso_pin, self._mosi_pin, self._clock_pin,
self._baud, self._spi_flags)
def _get_lsb_first(self):
return bool(self._spi_flags & 0xc000)
def _set_lsb_first(self, value):
self._check_open()
self._factory.connection.bb_spi_close(self._select_pin)
self._spi_flags = (
(self._spi_flags & ~0xc000)
| (bool(value) << 14)
| (bool(value) << 15)
)
self._factory.connection.bb_spi_open(
self._select_pin, self._miso_pin, self._mosi_pin, self._clock_pin,
self._baud, self._spi_flags)
def transfer(self, data):
self._check_open()
count, data = self._factory.connection.bb_spi_xfer(self._select_pin, data)
if count < 0:
raise IOError('SPI transfer error %d' % count)
# Convert returned bytearray to list of ints. bb_spi only supports
# byte-sized words so no issues here
return [int(b) for b in data]
class PiGPIOHardwareSPIShared(SharedMixin, PiGPIOHardwareSPI):
@classmethod
def _shared_key(cls, factory, port, device):
return (factory, port, device)
class PiGPIOSoftwareSPIShared(SharedMixin, PiGPIOSoftwareSPI):
@classmethod
def _shared_key(cls, factory, clock_pin, mosi_pin, miso_pin, select_pin):
return (factory, select_pin)