def test_analog_sensor_average_read(patch_pigpio_i2c, mock_i2c_hardware, ads1x15, seed):
"""__________________________________________________________________________________________________________TEST #6
Performs a several updates before averaging AnalogSensor.data to determine if the result matches expectations
- Data loaded into the conversion register is gaussian normal about the expected value
"""
random.seed(seed)
pga = random.choice(ads1x15._CONFIG_VALUES[2])
kwargs = {
"MUX": random.choice(ads1x15._CONFIG_VALUES[1]),
"PGA": pga,
"MODE": random.choice(ads1x15._CONFIG_VALUES[3]),
"DR": random.choice(ads1x15._CONFIG_VALUES[4]),
'offset_voltage': round(random.uniform(-0.35, 0.35) * pga, 2),
'output_span': round(random.uniform(.75, 1.0) * pga, 2),
'conversion_factor': round(random.choice([-1, 1]) * random.uniform(1, 10), 2)
}
mock = mock_i2c_hardware(
i2c_bus=1,
i2c_address=ads1x15._DEFAULT_ADDRESS,
n_registers=4,
reg_values=[b'\x00\x00', b'\x85\x83']
)
def voltage(bytes_value):
val = int.from_bytes(bytes_value, 'big', signed=True)
result = val*kwargs['PGA'] / 32767
return result
def gaussian_bytes(mu):
def _gauss():
val = random.gauss(mu, mu/1000)
result = int(round(val)).to_bytes(2, 'big')
return result
return _gauss
n_iter = 1000
target = random.randint(1000, 20000)
pig = PigpioConnection()
pig.add_mock_hardware(mock['device'], mock['i2c_address'], mock['i2c_bus'])
ads = ads1x15(pig=pig)
a_sensor = AnalogSensor(ads, **kwargs)
a_sensor.maxlen_data = n_iter
gauss_cannon = gaussian_bytes(target)
bytes_data = [gauss_cannon() for _ in range(n_iter)]
avg_voltage = np.mean([voltage(byt) for byt in bytes_data])
expected_value = kwargs['conversion_factor'] * (avg_voltage - kwargs['offset_voltage']) / kwargs['output_span']
for i in range(n_iter):
pig.mock_i2c[1][mock['i2c_address']].write_mock_hardware_register(0, bytes_data[i])
a_sensor.update()
data = a_sensor.data
result_0 = a_sensor.get(average=True)
result_1 = data[:, 1].mean()
assert len(data) == n_iter
assert result_0 - result_1 < 0.1
assert result_0 - expected_value < 0.1
"""__________________________________________________________________________________________________________
def test_read_conversion(patch_pigpio_i2c, mock_i2c_hardware, ads1x15, seed):
"""_________________________________________________________________________________________________________TEST #10
Tests that the proper cfg is generated and written to the config register given kwargs, and tests that the
conversion register is properly read & converted to signed int
"""
random.seed(seed)
kwargs = {
"MUX": random.choice(ads1x15._CONFIG_VALUES[1]),
"PGA": random.choice(ads1x15._CONFIG_VALUES[2]),
"MODE": random.choice(ads1x15._CONFIG_VALUES[3]),
"DR": random.choice(ads1x15._CONFIG_VALUES[4])
}
conversion_bytes = token_bytes(2)
expected_val = int.from_bytes(conversion_bytes, 'big',
signed=True) * kwargs['PGA'] / 32767
mock = mock_i2c_hardware(i2c_bus=1,
i2c_address=ads1x15._DEFAULT_ADDRESS,
n_registers=4,
reg_values=[conversion_bytes, b'\x85\x83'])
pig = PigpioConnection()
pig.add_mock_hardware(mock['device'], mock['i2c_address'], mock['i2c_bus'])
ads = ads1x15(pig=pig)
expected_default_config = ads.config.unpack(0xC3E3)
expected_config = ads.config.unpack(ads.config.pack(0xC3E3, **kwargs))
assert ads.print_config() == expected_default_config
result = ads.read_conversion(**kwargs)
assert ads.print_config() == expected_config
assert result == expected_val
"""__________________________________________________________________________________________________________
def test_analog_sensor_single_read_drop_kwargs(patch_pigpio_i2c, mock_i2c_hardware, ads1x15, seed):
"""__________________________________________________________________________________________________________TEST #4
Same as the above test, except it will randomly drop kwargs to check that the default attributes are
properly filled in and that the read functions normally.
- Note: calibration values are stored seperately s.t. the later verification of the result can be calculated
even without the store the default calibration for later conversion.
"""
random.seed(seed)
kwargs = {
"MUX": random.choice(ads1x15._CONFIG_VALUES[1]),
"PGA": random.choice(ads1x15._CONFIG_VALUES[2]),
"MODE": random.choice(ads1x15._CONFIG_VALUES[3]),
"DR": random.choice(ads1x15._CONFIG_VALUES[4]),
'offset_voltage': 0,
'output_span': 5,
'conversion_factor': 10
}
kw_copy = kwargs.copy()
for field in kw_copy:
if random.getrandbits(1) and field is not "MUX":
del kwargs[field]
kw_copy[field] = dict(**ads1x15._DEFAULT_VALUES, **AnalogSensor._DEFAULT_CALIBRATION)[field]
mock = mock_i2c_hardware(
i2c_bus=1,
i2c_address=ads1x15._DEFAULT_ADDRESS,
n_registers=4,
reg_values=[
b'\x00\x00',
b'\x85\x83'
]
)
pig = PigpioConnection()
pig.add_mock_hardware(mock['device'], mock['i2c_address'], mock['i2c_bus'])
ads = ads1x15(pig=pig)
a_sensor = AnalogSensor(ads, **kwargs)
n_iter = 250
conversion_bytes = [token_bytes(2) for _ in range(n_iter)]
raw_voltage = [int.from_bytes(cb, 'big', signed=True) * kw_copy['PGA'] / 32767 for cb in conversion_bytes]
expected = [
kw_copy['conversion_factor'] * (rv - kw_copy['offset_voltage']) / kw_copy['output_span'] for rv in raw_voltage
]
for i in range(n_iter):
pig.mock_i2c[1][mock['i2c_address']].write_mock_hardware_register(0, conversion_bytes[i])
result = a_sensor.get()
assert round(result, 9) == round(expected[i], 9)
"""__________________________________________________________________________________________________________
def test_analog_sensor_single_read(patch_pigpio_i2c, mock_i2c_hardware, ads1x15, seed, pga, mode):
"""__________________________________________________________________________________________________________TEST #3
Tests the proper functioning of an AnalogSensor with random, but plausible, calibration.
- Performs a sequence of observations and verifies that each matches expectations and that the age of each reading
properly reflects called updates
"""
random.seed(seed)
kwargs = {
"MUX": random.choice(ads1x15._CONFIG_VALUES[1]),
"PGA": pga,
"MODE": mode,
"DR": random.choice(ads1x15._CONFIG_VALUES[4]),
'offset_voltage': round(random.uniform(-0.35, 0.35) * pga, 2),
'output_span': round(random.uniform(.75, 1.0) * pga, 2),
'conversion_factor': round(random.choice([-1, 1]) * random.uniform(1, 10), 2)
}
mock = mock_i2c_hardware(
i2c_bus=1,
i2c_address=ads1x15._DEFAULT_ADDRESS,
n_registers=4,
reg_values=[
b'\x00\x00',
b'\x85\x83'
]
)
pig = PigpioConnection()
pig.add_mock_hardware(mock['device'], mock['i2c_address'], mock['i2c_bus'])
ads = ads1x15(pig=pig)
a_sensor = AnalogSensor(ads, **kwargs)
n_iter = 250
conversion_bytes = [token_bytes(2) for _ in range(n_iter)]
raw_voltage = [int.from_bytes(cb, 'big', signed=True) * kwargs['PGA'] / 32767 for cb in conversion_bytes]
expected = [
kwargs['conversion_factor'] * (rv - kwargs['offset_voltage']) / kwargs['output_span'] for rv in raw_voltage
]
for i in range(n_iter):
pig.mock_i2c[1][mock['i2c_address']].write_mock_hardware_register(0, conversion_bytes[i])
result = a_sensor.get()
assert round(result, 9) == round(expected[i], 9)
"""__________________________________________________________________________________________________________
def test_analog_sensor_kwarg_exceptions(patch_pigpio_i2c, mock_i2c_hardware, ads1x15, seed, pga, mode):
"""__________________________________________________________________________________________________________TEST #5
Tests that an exception is properly raised when either:
- a kwarg is passed that it unrecognized
- MUX is not passed in kwargs
"""
random.seed(seed)
kwargs = {
"MUX": random.choice(ads1x15._CONFIG_VALUES[1]),
"PGA": pga,
"MODE": mode,
"DR": random.choice(ads1x15._CONFIG_VALUES[4]),
'offset_voltage': round(random.uniform(-0.35, 0.35) * pga, 2),
'output_span': round(random.uniform(.75, 1.0) * pga, 2),
'conversion_factor': round(random.choice([-1, 1]) * random.uniform(1, 10), 2)
}
mock = mock_i2c_hardware(
i2c_bus=1,
i2c_address=ads1x15._DEFAULT_ADDRESS,
n_registers=4,
reg_values=[
b'\x00\x00',
b'\x85\x83'
]
)
pig = PigpioConnection()
pig.add_mock_hardware(mock['device'], mock['i2c_address'], mock['i2c_bus'])
ads = ads1x15(pig=pig)
with pytest.raises(TypeError):
bad_kwargs = kwargs.copy()
bad_kwargs['bad_key'] = 'bad_value'
AnalogSensor(ads, **bad_kwargs)
with pytest.raises(TypeError):
bad_kwargs = kwargs.copy()
del bad_kwargs['MUX']
AnalogSensor(ads, **bad_kwargs)
"""__________________________________________________________________________________________________________
def test_i2c_device(patch_pigpio_i2c, mock_i2c_hardware, seed):
"""__________________________________________________________________________________________________________TEST #5
Tests the various basic I2CDevice methods, open, close, read, write, etc.
- Note: i2c_device.read_device() returns raw bytes (assumed to have big-endian ordering.) read_register, on the
other hand, returns the integer representation of those bytes. write_device and write_register take an integer
argument which is the written to the device register as a big-endian two's complement.
- The RPi is native little endian, so to simulate/test the byte-swapping that occurs over I2C we generate a
random 16-bit integer (`data`), write it to the register, and read it back.
- If the int->byte-> int conversions in i2c_device are working correctly, we should expect one of two possible
values to be returned (depending on whether read_device() or read_register() is called)
- read_device() should return the big-endian two's complement of `data`
- read_register() should just return `data`
"""
results = []
random.seed(seed)
mock = mock_i2c_hardware()
n_registers = len(mock['values'])
data = [random.getrandbits(15) for _ in range(n_registers)]
signed = random.getrandbits(1)
expected = [data[0].to_bytes(2, 'big', signed=signed)
] if n_registers == 1 else data
pig = PigpioConnection()
pig.add_mock_hardware(mock['device'], mock['i2c_address'], mock['i2c_bus'])
i2c_device = I2CDevice(mock['i2c_address'], mock['i2c_bus'], pig=pig)
assert i2c_device.pigpiod_ok
if n_registers == 1:
i2c_device.write_device(data[0], signed=signed)
results.append(i2c_device.read_device()[1])
else:
for register in range(n_registers):
i2c_device.write_register(register, data[register], signed=signed)
results.append(i2c_device.read_register(register, signed=signed))
i2c_device._close()
assert not i2c_device._pig.mock_i2c[mock['i2c_bus']]
assert results == expected
"""__________________________________________________________________________________________________________
def test_sfm_single_read(patch_pigpio_i2c, mock_i2c_hardware, seed):
"""__________________________________________________________________________________________________________TEST #7
Tests the proper functioning of an SFM sensor. similar to single read of analog sensor, except starts with 4 bytes
in the register and discards two (just like in real life)
"""
random.seed(seed)
mock = mock_i2c_hardware(
i2c_bus=1,
i2c_address=SFM3200._DEFAULT_ADDRESS,
reg_values=[b'\x00\x00']
)
pig = PigpioConnection()
pig.add_mock_hardware(mock['device'], mock['i2c_address'], mock['i2c_bus'])
sfm = SFM3200(address=mock['i2c_address'], i2c_bus=mock['i2c_bus'], pig=pig)
n_iter = random.randint(100, 1000)
conversion_bytes = [token_bytes(4) for _ in range(n_iter)]
raw_int = [int.from_bytes(cb[:2], 'big') for cb in conversion_bytes]
expected = [(rv - sfm._FLOW_OFFSET) / sfm._FLOW_SCALE_FACTOR for rv in raw_int]
for i in range(n_iter):
pig.mock_i2c[1][mock['i2c_address']].write_mock_hardware_register(0, conversion_bytes[i])
result = sfm.get()
assert round(result, 10) == round(expected[i], 10)
"""__________________________________________________________________________________________________________
def test_mock_pigpio_i2c(patch_pigpio_i2c, mock_i2c_hardware, seed):
"""__________________________________________________________________________________________________________TEST #4
Tests the functionality of the mock pigpio i2c device interface. More specifically, tests that:
- mock hardware devices are initialized correctly
- mock handles, i2c_open(), and i2c_close() can be used to add, interact with, and remove mock hardware devices
- correct functioning of i2c_open is implied by the read/write tests
- the correct functioning of i2c_close() is ascertained from the assertion that pig.mock_i2c[i2c_bus] is empty
- mock i2c read and write functions work as intended:
- This is three tests in one. For each register of each mock hardware device:
1) Read the register with i2c_read and store the result in results['init']. We expect it to be the value
from the correct register of the matching mock_device (expected['init'])
2) Write two random bytes to the register with i2c_write. Look at the actual contents of the target register
and put them in results['write']. We expect them to be the same as the two random bytes we generated.
3) Read the register with i2c_read again and put the results in expected['read']. These should also match
the two random bytes from the 'write' test.
-> Assert that the results match what we expect
- if there is only one register on the device, test read_device() and write_device() instead of read_register()
and write_register() -> this matches how such a device would be interacted with in practice.
"""
random.seed(seed)
n_devices = random.randint(1, 20)
address_pool = random.sample(range(128), k=n_devices)
pig = PigpioConnection()
mocks = []
for i in range(n_devices):
mock = mock_i2c_hardware(i2c_address=address_pool.pop())
pig.add_mock_hardware(mock['device'], mock['i2c_address'],
mock['i2c_bus'])
mock['handle'] = pig.i2c_open(mock['i2c_bus'], mock['i2c_address'])
mocks.append(mock)
for mock_device in mocks:
handle = mock_device['handle']
bus = mock_device['i2c_bus']
address = mock_device['i2c_address']
results = {'init': [], 'write': [], 'read': []}
expected = {'init': [], 'write': [], 'read': []}
for reg in range(len(mock_device['values'])):
expected['init'] = mock_device['values'][reg]
expected['write'] = token_bytes(2)
expected['read'] = expected['write']
if len(mock_device['values']) == 1:
results['init'] = pig.i2c_read_device(handle, 2)[1]
pig.i2c_write_device(handle, expected['write'])
results['write'] = pig.mock_i2c[bus][address].registers[0][-1]
results['read'] = pig.i2c_read_device(handle, 2)[1]
else:
results['init'] = pig.i2c_read_i2c_block_data(handle,
reg,
count=2)[1]
pig.i2c_write_i2c_block_data(handle, reg, expected['write'])
results['write'] = pig.mock_i2c[bus][address].registers[reg][
-1]
results['read'] = pig.i2c_read_i2c_block_data(handle,
reg,
count=2)[1]
assert results == expected
pig.i2c_close(handle)
assert not pig.mock_i2c[0]
assert not pig.mock_i2c[1]
assert not pig.mock_i2c['spi']
"""__________________________________________________________________________________________________________