def get(self, nmea_sentences=None, timeout=15):
"""Get NMEA sentences
Parameters
----------
nmea_sentence : list of str, NMEA sentence codes to return i.e. 'GSV'
timeout : int, seconds to wait for data before returning
Returns
-------
list of str, NMEA sentences
"""
if nmea_sentences is None:
nmea_sentences = self.metadata.supported_nmea_sentences
check = {s: False for s in nmea_sentences}
t0 = time.time()
while sum([x == False for x in check.values()]) > 0:
if time.time() - t0 > timeout: # timeout in seconds
break
for single_line in self.raw_get():
sentence_type = single_line[3:6]
if (sentence_type in nmea_sentences) & ("*" in single_line):
gps_data = single_line.split("*")
gps_cs = gps_data[1]
gps_data = gps_data[0][1:]
driver_cs = calc_checksum(gps_data)
if gps_cs == driver_cs:
check[sentence_type] = single_line
return [v for k, v in check.items()]
def _connect(_round):
self.wlan.connect(ssid=self.ssid,
bssid=self.bssid,
auth=(WLAN.WPA2, self.key))
t0 = time.time()
while not self.wlan.isconnected():
machine.idle()
if time.time() - t0 > self.connect_timeout:
return False
if self.verbose:
print(_round, time.time())
return True
def measure_single_shot_blocking(self):
"""On-demand measurement of CO2 concentration, relative humidity
and temperature. See Ch 3.10.1
Returns
-------
co2 : int, CO2 concentration in ppm
t : float, temperature in degrees Celsius
rh : int, relative humidity in percent
"""
t0 = time.time()
self.measure_single_shot()
time.sleep(5) # 5000 ms
self.dt = time.time() - t0
return self.read_measurement()
def measure(self, verbose=False):
"""Get the temperature, pressure and humidity"""
self._new_data = 0
t0 = time.time()
cx = 1
while True:
self.get_measurement_status()
dt = (time.time() - t0)
if self._measuring == 1:
if verbose:
print('Still measuring, waiting 1 second...')
time.sleep(1)
elif self._new_data == 1:
if verbose:
print('New data found!')
break
elif dt > 5:
if verbose:
print('Timeout waiting for new data :(')
return False
if verbose:
print('While loop %s' % cx)
cx += 1
data = self.bus.read_register_nbit(0x1F, 3) # 0x1F
self._adc_pres = ((data[0] << 16) + (data[1] << 8) + data[2]) >> 4
data = self.bus.read_register_nbit(0x22, 3) # 0x22
self._adc_temp = ((data[0] << 16) + (data[1] << 8) + data[2]) >> 4
data = self.bus.read_register_nbit(0x25, 3) # 0x25
self._adc_hum = (data[0] << 8) + data[1]
_gas_r_msb = self.bus.read_register_8bit(0x2A)
_gas_r_lsb = self.bus.read_register_8bit(0x2B)
self._adc_gas = (_gas_r_msb << 2) + (_gas_r_lsb >> 6)
self._gas_valid = (_gas_r_lsb >> 5) & 0b1
self._heat_stab = (_gas_r_lsb >> 4) & 0b1
self._gas_range = _gas_r_lsb & 0b1111 # 0x2B <4:0>
return True
def measured_values_blocking(self, verbose=False):
"""Block and poll until new data is available
Parameters
----------
dt : int, seconds to pause between polling requests
timeout : int, maximum seconds to poll
# continuous : bool, if True do not stop measurement to read latest data
verbose : bool, print debug statements
"""
self.start_measurement()
time.sleep(self.blocking_settle_dt)
t0 = time.time()
while (time.time() - t0 < self.blocking_timeout):
if self.data_ready():
self.stop_measurement()
return self.measured_values()
if verbose:
print('waiting...')
return False