js-gpiozero
Version:
A simple interface to GPIO devices with Raspberry Pi using nodejs
612 lines (524 loc) • 19.9 kB
JavaScript
const Pin = require("./index.js").Pin;
const exc = require("../exc.js");
const assert = require('chai').assert;
const isclose = require('../compat.js').isclose;
const inherit = require('../tools.js').inherit;
let _PINS = [];
/**
* A mock pin used primarily for testing. This class does *not* support PWM.
*
* @param {int} number - GPIO Pin to simulate.
* @returns {MockPin} - The pin that has been instatiated or the pin already associated with this pin number.
* @class
* @augments Pin
*/
function MockPin(number) {
if (number < 0 || number > 54) {
throw new Error('invalid pin ' + number.toString() + ' specified (must be 0..53)');
}
const old_pin = _PINS[number];
if (old_pin === undefined) {
Pin.call(this);
_PINS[number] = this;
this._number = number;
this._function = 'input';
this._state = false;
this._pull = 'floating';
this._bounce = null;
this._edges = 'both';
this._when_changed = null;
this.clear_states();
return this;
}
// Ensure the pin class expected supports PWM (or not)
//if issubclass(cls, MockPWMPin) != isinstance(old_pin, MockPWMPin):
// raise ValueError('pin %d is already in use as a %s' % (number, old_pin.__class__.__name__))
return old_pin;
}
MockPin.prototype = inherit(Pin.prototype);
MockPin.prototype.constructor = MockPin;
MockPin.prototype.when_changed = function(next) {
this._when_changed = next;
}
MockPin.prototype.clear_states = function() {
this._last_change = (new Date()).getTime();
this.states = [{
time: 0.0,
state: this._state
}];
};
MockPin.prototype.toString = function () {
return 'MOCK'+this._number;
}
MockPin.prototype.state_history = function() {
return this.states;
};
MockPin.prototype.state = function(value) {
if (value === undefined) {
return this._state;
}
if (this._function !== 'output') {
throw new exc.PinSetInput('cannot set state of pin ' + this);
}
if (value !== '0' && value !== '1' && value !== true && value !== false) {
throw new exc.PinSetInput('Invalid Value - must be 1 or 0 not ' + value.toString());
}
this._change_state(typeof(value) !== "boolean" ? Boolean(value) : value);
};
MockPin.prototype._change_state = function(value) {
if (this._state !== value) {
var t = (new Date()).getTime();
this._state = value;
this.states.push({
time: t - this._last_change,
state: value
});
this._last_change = t;
return true;
}
return false;
};
MockPin.prototype.pin_function = function(value) {
if (value === undefined) {
return this._function;
}
if (value === 'input' || value === 'output') {
this._function = value;
if (value === 'input') {
//# Drive the input to the pull
//self._set_pull(self._get_pull())
}
} else {
throw new exc.PinSetInput('Invalid Value - must be input or output not ' + value.toString());
}
};
MockPin.prototype.close = function() {
this.when_changed = undefined;
this._function = 'input';
};
MockPin.prototype.frequency = function(value) {
if (value === undefined) {
return;
}
throw new exc.PinPWMUnsupported();
};
MockPin.prototype.number = function() {
return this._number;
};
MockPin.prototype.assert_states = function(expected) {
// Tests that the pin went through the expected states (a list of values)
for (let i = 0, len = expected.length; i < len; i++) {
const actual = this.state_history()[i].state;
assert(isclose(actual, expected[i], undefined, 10), actual + " not equal to " + expected[i]);
}
};
MockPin.prototype.assert_states_and_times = function(expected) {
// Tests that the pin went through the expected states at the expected
// times (times are compared with a tolerance of tens-of-milliseconds as
// that's about all we can reasonably expect in a non-realtime
// environment on a Pi 1)
assert(expected.length <= this.state_history().length, 'Expected length:' + expected.length + ' Actual length:' + this.state_history().length);
for (let i = 0; i < expected.length; i++) {
let actual = this.state_history()[i].state;
assert(isclose(actual, expected[i].state, 0.05, undefined), actual + " not equal to " + expected[i].state);
if (expected[i].time === 0) {
actual = this.state_history()[i].time;
assert(actual === expected[i].time, "Times are not equal Expected:" + expected[i].time + " Actual:" + actual);
} else if (expected[i].time !== 1) {
actual = this.state_history()[i].time;
assert(isclose(actual, expected[i].time, undefined, 10), actual + " not equal to " + expected[i].time);
}
}
};
MockPin.prototype.pull = function (value) {
if (value === undefined) {
return this._pull;
}
assert(this._function === 'input', 'Pin function is not set to input');
assert(['floating', 'up', 'down'].indexOf(value) !== -1, 'Invalid pull value');
this._pull = value;
if (value === 'up') {
this.drive_high();
} else if (value === 'down') {
this.drive_low();
}
};
MockPin.prototype.drive_high = function () {
assert(this._function === 'input', 'Pin function is not set to input');
if (this._change_state(true)) {
if (['both', 'rising'].indexOf(this._edges) !== -1) {
if(this._when_changed !== null) {
this._when_changed();
}
}
}
};
MockPin.prototype.drive_low = function () {
assert(this._function === 'input', 'Pin function is not set to input');
if (this._change_state(false)) {
if (['both', 'rising'].indexOf(this._edges) !== -1) {
if(this._when_changed !== null) {
this._when_changed();
}
}
}
};
exports.MockPin = MockPin;
function clear_pins() {
_PINS = {};
}
exports.clear_pins = clear_pins;
function MockPWMPin(number) {
MockPin.call(this, number);
this._state = 0.0;
this.clear_states();
this._frequency = undefined;
}
MockPWMPin.prototype = inherit(MockPin.prototype);
MockPWMPin.prototype.constructor = MockPWMPin;
exports.MockPWMPin = MockPWMPin;
MockPWMPin.prototype.close = function() {
this.frequency(undefined);
MockPin.prototype.close.call(this);
};
MockPWMPin.prototype.frequency = function(value) {
if (value === undefined) {
return this._frequency;
}
if (this._function !== 'output') {
throw new exc.PinSetInput("Pin is not set for output function");
}
if (value === -1) {
this._frequency = undefined;
this._change_state(0.0);
} else {
this._frequency = value;
}
};
MockPWMPin.prototype.state = function(value) {
if (value === undefined) {
return this._state;
}
if (this._function !== 'output') {
throw new exc.PinSetInput('cannot set state of pin ' + this);
}
if (value < 0 || value > 1) {
throw new exc.OutputDeviceBadValue("initial_value must be between 0 and 1, actual=:" + value);
}
this._change_state(parseFloat(value));
};
MockPWMPin.prototype.blink = function(on_time, off_time, fade_in_time, fade_out_time, n, fps, callback) {
this.on_time = (on_time === undefined ? 1 : on_time);
this.off_time = (off_time === undefined ? 1 : off_time);
this.fade_in_time = (fade_in_time === undefined ? 0 : fade_in_time);
this.fade_out_time = (fade_out_time === undefined ? 0 : fade_out_time);
this.fps = (fps === undefined ? 50 : fps);
this.n = (n === undefined ? 0 : n);
this.sequence = [];
this.blink_callback = callback;
var i = 0;
if (this.fade_in_time > 0) {
for (i = 0; i < this.fps * this.fade_in_time; i++) {
this.sequence.push({
value: i * (1 / this.fps) / this.fade_in_time,
delay: 1 / this.fps
});
}
}
this.sequence.push({
value: 1,
delay: this.on_time
});
if (this.fade_out_time > 0) {
for (i = 0; i < this.fps * this.fade_out_time; i++) {
this.sequence.push({
value: 1 - (i * (1 / this.fps)) / this.fade_out_time,
delay: 1 / this.fps
});
}
}
this.sequence.push({
value: 0,
delay: this.off_time
});
if (this.n > 0) {
for (i = 0; i < (this.n - 1); i++) {
this.sequence = this.sequence.concat(this.sequence);
}
var nextStep = this.sequence.pop();
this.state(nextStep.value);
var that = this;
this._blink_timer = setTimeout(that._run_blink, nextStep.delay, this.sequence, this);
}
};
MockPWMPin.prototype._run_blink = function(sequence, that) {
if (sequence.length > 0) {
var nextStep = sequence.pop();
that.state(nextStep.value);
that._blink_timer = setTimeout(that._run_blink, nextStep.delay, sequence, that);
} else if (that.blink_callback !== undefined) {
that.blink_callback();
}
};
/**
* This derivative of {@link MockPin} emulates a pin with a physical pull-up resistor.
*
* @param {int} number - GPIO Pin number that is being simulated.
* @class
* @augments MockPin
*/
function MockPulledUpPin(number) {
MockPin.call(this, number);
}
MockPulledUpPin.prototype = inherit (MockPin.prototype);
MockPulledUpPin.prototype.constructor = MockPulledUpPin;
MockPulledUpPin.prototype.pull = function (value) {
if (value !== 'up') {
throw new exc.PinFixedPull('pin has a physical pull-up resistor');
}
}
exports.MockPulledUpPin = MockPulledUpPin;
/*
def pi_info(cls):
return pi_info('a21041') # Pretend we're a Pi 2B
def __repr__(self):
return 'MOCK%d' % self._number
@property
def number(self):
return self._number
def close(self):
self.when_changed = None
self.function = 'input'
def _get_frequency(self):
return None
def _set_frequency(self, value):
if value is not None:
raise PinPWMUnsupported()
def _get_pull(self):
return self._pull
def _set_pull(self, value):
assert self._function == 'input'
assert value in ('floating', 'up', 'down')
self._pull = value
if value == 'up':
self.drive_high()
elif value == 'down':
self.drive_low()
def _get_bounce(self):
return self._bounce
def _set_bounce(self, value):
# XXX Need to implement this
self._bounce = value
def _get_edges(self):
return self._edges
def _set_edges(self, value):
assert value in ('none', 'falling', 'rising', 'both')
self._edges = value
def _get_when_changed(self):
return self._when_changed
def _set_when_changed(self, value):
self._when_changed = value
def drive_high(self):
assert self._function == 'input'
if self._change_state(True):
if self._edges in ('both', 'rising') and self._when_changed is not None:
self._when_changed()
def drive_low(self):
assert self._function == 'input'
if self._change_state(False):
if self._edges in ('both', 'falling') and self._when_changed is not None:
self._when_changed()
def clear_states(self):
self._last_change = time()
self.states = [PinState(0.0, self._state)]
def assert_states(self, expected_states):
# Tests that the pin went through the expected states (a list of values)
for actual, expected in zip(self.states, expected_states):
assert actual.state == expected
def assert_states_and_times(self, expected_states):
# Tests that the pin went through the expected states at the expected
# times (times are compared with a tolerance of tens-of-milliseconds as
# that's about all we can reasonably expect in a non-realtime
# environment on a Pi 1)
for actual, expected in zip(self.states, expected_states):
assert isclose(actual.timestamp, expected[0], rel_tol=0.05, abs_tol=0.05)
assert isclose(actual.state, expected[1])
class MockChargingPin(MockPin):
"""
This derivative of :class:`MockPin` emulates a pin which, when set to
input, waits a predetermined length of time and then drives itself high
(as if attached to, e.g. a typical circuit using an LDR and a capacitor
to time the charging rate).
"""
def __init__(self, number):
super(MockChargingPin, self).__init__()
self.charge_time = 0.01 # dark charging time
self._charge_stop = Event()
self._charge_thread = None
def _set_function(self, value):
super(MockChargingPin, self)._set_function(value)
if value == 'input':
if self._charge_thread:
self._charge_stop.set()
self._charge_thread.join()
self._charge_stop.clear()
self._charge_thread = Thread(target=self._charge)
self._charge_thread.start()
elif value == 'output':
if self._charge_thread:
self._charge_stop.set()
self._charge_thread.join()
def _charge(self):
if not self._charge_stop.wait(self.charge_time):
try:
self.drive_high()
except AssertionError:
# Charging pins are typically flipped between input and output
# repeatedly; if another thread has already flipped us to
# output ignore the assertion-error resulting from attempting
# to drive the pin high
pass
class MockTriggerPin(MockPin):
"""
This derivative of :class:`MockPin` is intended to be used with another
:class:`MockPin` to emulate a distance sensor. Set :attr:`echo_pin` to the
corresponding pin instance. When this pin is driven high it will trigger
the echo pin to drive high for the echo time.
"""
def __init__(self, number):
super(MockTriggerPin, self).__init__()
self.echo_pin = None
self.echo_time = 0.04 # longest echo time
self._echo_thread = None
def _set_state(self, value):
super(MockTriggerPin, self)._set_state(value)
if value:
if self._echo_thread:
self._echo_thread.join()
self._echo_thread = Thread(target=self._echo)
self._echo_thread.start()
def _echo(self):
sleep(0.001)
self.echo_pin.drive_high()
sleep(self.echo_time)
self.echo_pin.drive_low()
class MockSPIClockPin(MockPin):
"""
This derivative of :class:`MockPin` is intended to be used as the clock pin
of a mock SPI device. It is not intended for direct construction in tests;
rather, construct a :class:`MockSPIDevice` with various pin numbers, and
this class will be used for the clock pin.
"""
def __init__(self, number):
super(MockSPIClockPin, self).__init__()
if not hasattr(self, 'spi_devices'):
self.spi_devices = []
def _set_state(self, value):
super(MockSPIClockPin, self)._set_state(value)
for dev in self.spi_devices:
dev.on_clock()
class MockSPISelectPin(MockPin):
"""
This derivative of :class:`MockPin` is intended to be used as the select
pin of a mock SPI device. It is not intended for direct construction in
tests; rather, construct a :class:`MockSPIDevice` with various pin numbers,
and this class will be used for the select pin.
"""
def __init__(self, number):
super(MockSPISelectPin, self).__init__()
if not hasattr(self, 'spi_device'):
self.spi_device = None
def _set_state(self, value):
super(MockSPISelectPin, self)._set_state(value)
if self.spi_device:
self.spi_device.on_select()
class MockSPIDevice(object):
def __init__(
self, clock_pin, mosi_pin, miso_pin, select_pin=None,
clock_polarity=False, clock_phase=False, lsb_first=False,
bits_per_word=8, select_high=False):
self.clock_pin = MockSPIClockPin(clock_pin)
self.mosi_pin = None if mosi_pin is None else MockPin(mosi_pin)
self.miso_pin = None if miso_pin is None else MockPin(miso_pin)
self.select_pin = None if select_pin is None else MockSPISelectPin(select_pin)
self.clock_polarity = clock_polarity
self.clock_phase = clock_phase
self.lsb_first = lsb_first
self.bits_per_word = bits_per_word
self.select_high = select_high
self.rx_bit = 0
self.rx_buf = []
self.tx_buf = []
self.clock_pin.spi_devices.append(self)
self.select_pin.spi_device = self
def __enter__(self):
return self
def __exit__(self, exc_type, exc_value, exc_tb):
self.close()
def close(self):
if self in self.clock_pin.spi_devices:
self.clock_pin.spi_devices.remove(self)
if self.select_pin is not None:
self.select_pin.spi_device = None
def on_select(self):
if self.select_pin.state == self.select_high:
self.on_start()
def on_clock(self):
# Don't do anything if this SPI device isn't currently selected
if self.select_pin is None or self.select_pin.state == self.select_high:
# The XOR of the clock pin's values, polarity and phase indicates
# whether we're meant to be acting on this edge
if self.clock_pin.state ^ self.clock_polarity ^ self.clock_phase:
self.rx_bit += 1
if self.mosi_pin is not None:
self.rx_buf.append(self.mosi_pin.state)
if self.miso_pin is not None:
try:
tx_value = self.tx_buf.pop(0)
except IndexError:
tx_value = 0
if tx_value:
self.miso_pin.drive_high()
else:
self.miso_pin.drive_low()
self.on_bit()
def on_start(self):
"""
Override this in descendents to detect when the mock SPI device's
select line is activated.
"""
self.rx_bit = 0
self.rx_buf = []
self.tx_buf = []
def on_bit(self):
"""
Override this in descendents to react to receiving a bit.
The :attr:`rx_bit` attribute gives the index of the bit received (this
is reset to 0 by default by :meth:`on_select`). The :attr:`rx_buf`
sequence gives the sequence of 1s and 0s that have been recevied so
far. The :attr:`tx_buf` sequence gives the sequence of 1s and 0s to
transmit on the next clock pulses. All these attributes can be modified
within this method.
The :meth:`rx_word` and :meth:`tx_word` methods can also be used to
read and append to the buffers using integers instead of bool bits.
"""
pass
def rx_word(self):
result = 0
bits = reversed(self.rx_buf) if self.lsb_first else self.rx_buf
for bit in bits:
result <<= 1
result |= bit
return result
def tx_word(self, value, bits_per_word=None):
if bits_per_word is None:
bits_per_word = self.bits_per_word
bits = [0] * bits_per_word
for bit in range(bits_per_word):
bits[bit] = value & 1
value >>= 1
assert not value
if not self.lsb_first:
bits = reversed(bits)
self.tx_buf.extend(bits)
*/