@Gijs I tried last pycom firware update 1.20.0.r7

@railmonitor thank you

@Wolli01 Don't have a Pycom module at hand to test, but does that actually return local time by default? If so, I wonder where it could possibly get the timezone from... But a quick glance through the code makes me think it doesn't, does it? You can control the timezone used by localtime (and mktime) using utime.timezone, but it's simplistic (just an offset from UTC), it does not handle automatic DST changes. If you want that to be handled for you (which seems overkill on such a device IMHO) you'll probably have to use an external library that supports it.

@paul-thornton said in How to send/receive LORAWAN MAC Commands?: https://docs.pycom.io/firmwareapi/pycom/network/lora.html#lorastats I'm not sure whether lora.stats() rx_timestamp is of use, it does not seem to represent a time value, but if it does, how do I convert it? [LORA ] 2019/02/21 04:51:55 (rx_timestamp=0, rssi=0, snr=0.0, sfrx=0, sftx=0, tx_trials=0, tx_power=14, tx_time_on_air=0, tx_counter=0, tx_frequency=0) [LORA ] 2019/02/21 04:52:04 (rx_timestamp=30539834, rssi=-45, snr=7.0, sfrx=3, sftx=5, tx_trials=1, tx_power=0, tx_time_on_air=57, tx_counter=0, tx_frequency=0) [LORA ] 2019/02/21 04:52:11 (rx_timestamp=38155453, rssi=-38, snr=8.0, sfrx=3, sftx=5, tx_trials=1, tx_power=0, tx_time_on_air=47, tx_counter=1, tx_frequency=0) [LORA ] 2019/02/21 09:04:47 (rx_timestamp=45778581, rssi=-43, snr=8.0, sfrx=3, sftx=5, tx_trials=1, tx_power=0, tx_time_on_air=47, tx_counter=2, tx_frequency=0) [LORA ] 2019/02/21 09:15:32 (rx_timestamp=690412324, rssi=-47, snr=6.0, sfrx=5, sftx=5, tx_trials=2, tx_power=0, tx_time_on_air=57, tx_counter=4, tx_frequency=0) [LORA ] 2019/02/21 09:15:38 (rx_timestamp=696682500, rssi=-48, snr=6.0, sfrx=5, sftx=5, tx_trials=1, tx_power=0, tx_time_on_air=57, tx_counter=5, tx_frequency=0) [LORA ] 2019/02/21 09:15:44 (rx_timestamp=702935506, rssi=-47, snr=6.0, sfrx=5, sftx=5, tx_trials=1, tx_power=0, tx_time_on_air=57, tx_counter=6, tx_frequency=0)

@snehasg96 main.py is executed automatically when the device boots. If ouy wnat to run a script, like recv.py, manually, just enter at the REPL prompt (the one with >>>): import recv

@crumble also, is it fine to use the utime.time() in the receiver as well or just use it in the sender? Also i tried running the code after removing time.sleep() in the receiver but for some reason i still experience the same issue.

Hi, Have you fix it? I'm facing the same problem

@livius Hi. I have the issue, that the device does not start again after several cycles. That was a try to fix it... Update: Fixed the issue using WDT :-)

Did you ever get it work? Any advise for me, as I am in the exact same situation?

@jmarcelino said in Cheapest GPS for time sync only: Interesting alternative, but i will stay with GPS - it also work on ship and is really simple to use (mostly UART). As always i probably do not need position - but if i can get it than it sometimes can be usefull as a gadget. And can be simply repleaced by more accurate GPS without firmware modification. Then better is GPS for me here.

@soren current firmware is 1.6.13.b1 but i never have had problem with line number in error message Do you have line break as LF or CRLF or mixed?

Sleep() function actually suspends the processing of the thread in which it is called by the operating system, allowing other threads and processes to execute while it sleeps. With multiple threads and processes, sleep() suspends your thread - it uses next to zero processing power.

@robert-hh Thanks a lot! :)

@Emmanuel-Goudot Yes, that's the piece of code below, which works for my DHT22 on a Lopy. It is buried far below in a thread, where two people fight to get it running(https://forum.pycom.io/topic/1172/pure-python-library-for-reading-dht-sensor-on-pycom-boards). No clue what their problem is, since I consider it solved, even if not bullet proof. import time from machine import enable_irq, disable_irq, Pin class DTHResult: 'DHT sensor result returned by DHT.read() method' ERR_NO_ERROR = 0 ERR_MISSING_DATA = 1 ERR_CRC = 2 error_code = ERR_NO_ERROR temperature = -1 humidity = -1 def __init__(self, error_code, temperature, humidity): self.error_code = error_code self.temperature = temperature self.humidity = humidity def is_valid(self): return self.error_code == DTHResult.ERR_NO_ERROR class DTH: 'DHT sensor (dht11, dht21,dht22) reader class for Pycom' __pin = Pin('P3', mode=Pin.OPEN_DRAIN) __dhttype = 0 def __init__(self, pin, sensor=0): self.__pin = pin self.__pin(1) self.__dhttype = sensor def read(self): time.sleep(1) # send initial high #self.__send_and_sleep(1, 25000) # pull down to low #self.__send_and_sleep(0, 40000) # collect data into an array data = self.__collect_input() # parse lengths of all data pull up periods pull_up_lengths = self.__parse_data_pull_up_lengths(data) # if bit count mismatch, return error (4 byte data + 1 byte checksum) print(pull_up_lengths) if len(pull_up_lengths) != 40: return DTHResult(DTHResult.ERR_MISSING_DATA, 0, 0) # calculate bits from lengths of the pull up periods bits = self.__calculate_bits(pull_up_lengths) # we have the bits, calculate bytes the_bytes = self.__bits_to_bytes(bits) print(the_bytes) # calculate checksum and check checksum = self.__calculate_checksum(the_bytes) if the_bytes[4] != checksum: return DTHResult(DTHResult.ERR_CRC, 0, 0) # ok, we have valid data, return it [int_rh, dec_rh, int_t, dec_t, csum] = the_bytes if self.__dhttype==0: #dht11 rh = int_rh #dht11 20% ~ 90% t = int_t #dht11 0..50°C else: #dht21,dht22 rh = ((int_rh * 256) + dec_rh)/10 t = (((int_t & 0x7F) * 256) + dec_t)/10 if (int_t & 0x80) > 0: t *= -1 return DTHResult(DTHResult.ERR_NO_ERROR, t, rh) def __send_and_sleep(self, output, mysleep): self.__pin(output) time.sleep_us(mysleep) def __collect_input(self): # collect the data while unchanged found unchanged_count = 0 # this is used to determine where is the end of the data max_unchanged_count = 100 last = -1 data = [] m = [1]*500 # needs long sample size to grab all the bits from the DHT self.__pin(0) time.sleep_us(20000) self.__pin(1) irqf = disable_irq() for i in range(len(m)): m[i] = self.__pin() ## sample input and store value enable_irq(irqf) for i in range(len(m)): current = m[i] data.append(current) if last != current: unchanged_count = 0 last = current else: unchanged_count += 1 if unchanged_count > max_unchanged_count: break #print(data) return data def __parse_data_pull_up_lengths(self, data): STATE_INIT_PULL_DOWN = 1 STATE_INIT_PULL_UP = 2 STATE_DATA_FIRST_PULL_DOWN = 3 STATE_DATA_PULL_UP = 4 STATE_DATA_PULL_DOWN = 5 state = STATE_INIT_PULL_UP lengths = [] # will contain the lengths of data pull up periods current_length = 0 # will contain the length of the previous period for i in range(len(data)): current = data[i] current_length += 1 if state == STATE_INIT_PULL_DOWN: if current == 0: # ok, we got the initial pull down state = STATE_INIT_PULL_UP continue else: continue if state == STATE_INIT_PULL_UP: if current == 1: # ok, we got the initial pull up state = STATE_DATA_FIRST_PULL_DOWN continue else: continue if state == STATE_DATA_FIRST_PULL_DOWN: if current == 0: # we have the initial pull down, the next will be the data pull up state = STATE_DATA_PULL_UP continue else: continue if state == STATE_DATA_PULL_UP: if current == 1: # data pulled up, the length of this pull up will determine whether it is 0 or 1 current_length = 0 state = STATE_DATA_PULL_DOWN continue else: continue if state == STATE_DATA_PULL_DOWN: if current == 0: # pulled down, we store the length of the previous pull up period lengths.append(current_length) state = STATE_DATA_PULL_UP continue else: continue return lengths def __calculate_bits(self, pull_up_lengths): # find shortest and longest period shortest_pull_up = 1000 longest_pull_up = 0 for i in range(0, len(pull_up_lengths)): length = pull_up_lengths[i] if length < shortest_pull_up: shortest_pull_up = length if length > longest_pull_up: longest_pull_up = length # use the halfway to determine whether the period it is long or short halfway = shortest_pull_up + (longest_pull_up - shortest_pull_up) / 2 bits = [] for i in range(0, len(pull_up_lengths)): bit = False if pull_up_lengths[i] > halfway: bit = True bits.append(bit) return bits def __bits_to_bytes(self, bits): the_bytes = [] byte = 0 for i in range(0, len(bits)): byte = byte << 1 if (bits[i]): byte = byte | 1 else: byte = byte | 0 if ((i + 1) % 8 == 0): the_bytes.append(byte) byte = 0 #print(the_bytes) return the_bytes def __calculate_checksum(self, the_bytes): return the_bytes[0] + the_bytes[1] + the_bytes[2] + the_bytes[3] & 255