def setup_phidget():
log.i("Setting up sensor")
voltageRatioInput0 = VoltageRatioInput()
voltageRatioInput0.setIsHubPortDevice(True)
voltageRatioInput0.setHubPort(0)
voltageRatioInput0.setOnSensorChangeHandler(onSensorChange)
voltageRatioInput0.openWaitForAttachment(5000)
voltageRatioInput0.setSensorType(VoltageRatioSensorType.SENSOR_TYPE_1120)
voltageRatioInput0.setDataInterval(1)
log.i("sensor ready")
return voltageRatioInput0
def main():
"The main function: loads an input and waits until terminated."
try:
try:
channel = VoltageRatioInput()
except PhidgetException as e:
sys.stderr.write(
"Runtime Error -> Creating VoltageRatioInput: \n\t")
display_error(e)
raise
except RuntimeError as e:
sys.stderr.write(
"Runtime Error -> Creating VoltageRatioInput: \n\t" + e)
raise
channel.setChannel(0)
channel.setOnAttachHandler(on_attach)
channel.setOnErrorHandler(on_error)
channel.setOnVoltageRatioChangeHandler(on_voltage_change)
channel.setOnSensorChangeHandler(on_sensor_change)
print("\nOpening and Waiting for Attachment...")
try:
channel.openWaitForAttachment(5000)
# Set the sensor type to the 10-80cm distance one
channel.setSensorType(
VoltageRatioSensorType.SENSOR_TYPE_1101_SHARP_2Y0A21)
except PhidgetException as e:
print_open_error(e, channel)
return
print("Sampling data for 10 seconds.")
while True:
time.sleep(60)
return
except PhidgetException as e:
sys.stderr.write("\nExiting with error(s)...")
display_error(e)
traceback.print_exc()
return
finally:
print("Cleaning up...")
channel.setOnVoltageRatioChangeHandler(None)
channel.setOnSensorChangeHandler(None)
channel.close()
class Distance:
"""A glorified wrapper over the distance sensor."""
name = None # type: str
value = None # type: float
valid = None # type: Optional[bool]
def __init__(self, name: str, channel: int):
self.name = name
self.value = 0
self.valid = None
self.lock = threading.Lock()
self.phidget = VoltageRatioInput()
self.phidget.setChannel(channel)
self.phidget.setOnSensorChangeHandler(self._on_change)
self.phidget.setOnErrorHandler(self._on_error)
def _on_change(self, _, value, _unit):
"Callback for when the sensor's input is changed." ""
with self.lock:
if not self.valid or abs(self.value - value) > 0.05:
# Update properties and notify observers
if self.name == "front_dist_0" or self.name == "front_dist_1":
LOG.debug("%s = %s%s", self.name, value, _unit.symbol)
self.value = value
self.valid = True
def get(self) -> float:
""" Returns the value of the sensors data """
with self.lock:
data = self.value
return data
def get_valid(self) -> Optional[bool]:
""" Returns the true/false if the sensor reading is valid"""
with self.lock:
return self.valid
def _on_error(self, ph, code, msg):
"""Callback for when the sensor detects receives an error.
We have a special implementation, as we want to handle the case where
the input is out of range.
"""
if code == 4103:
# Mark as malformed and notify observers
with self.lock:
if self.valid or self.valid is None:
LOG.warning("%s is out of bounds", self.name)
self.valid = False
else:
on_error(ph, code, msg)
def __enter__(self):
"""Attach this sensor and configure it with various properties.
For now, we subscribe to updates every 50ms (20Hz).
"""
self.phidget.openWaitForAttachment(ATTACHMENT_TIMEOUT)
self.phidget.setDataInterval(50)
self.phidget.setSensorType(
VoltageRatioSensorType.SENSOR_TYPE_1101_SHARP_2D120X)
LOG.info("Attached %s", self.name)
return self
def __exit__(self, _a, _b, _c):
self.phidget.setOnErrorHandler(None)
self.phidget.setOnSensorChangeHandler(None)
self.phidget.close()