E220 LoRa Receive-Intervall and MycroPython and Arduino Env communication (UnicodeError:)

Hi Renzo,

if the transmitter sends within 2sec, then the Micropython programme as receiver is terminated with the error unicode-error at line 636 in lora_e220.py.
What could be the reason for this? The message is only a few bytes long:
“Hello World! 1”. The next message is then “Hello World! 2” and so on.

best regards
Woto

Hi Renzo,
excuse me for the late answer.

I will do it today in the evening.

best regards,
woto

Hi Renzo,
I have now found a little time to reproduce the error.

When I send a message every second I get the following message in the Thonny editor:

Traceback (most recent call last):
  File "<stdin>", line 127, in <module>
  File "/lib/LoraWanE220/lora_e220.py", line 636, in receive_message
UnicodeError: 

Maybe you can help me.

best regards
Woto

Hi Renzo,

I send with the following command:
e220ttl.sendFixedMessage(0, DESTINATION_ADDL, 18, DateTimeStr + " ,Hello, world?" + String (i));

The variable DateTimeStr is:

DateTime nowTime = MCP7940.now(); // get the current time
String DateTimeStr = String(nowTime.year()) + "." + String(nowTime.month()) + "." + String(nowTime.day()) + " " + String(nowTime.hour()) + ":" + String(nowTime.minute()) + ":" + String(nowTime.second());

OWN_ADDH = 0x00
OWN_ADDL = 0x01
i is an integer

If I send all 6s, everything is fine. Only if I send every second does this message appear and the programme stops.

Hi Renzo,
yes, that’s right.

best regards
Woto

The sender is a ATTiny1616 and the receiver is a Rapsberry Pi pico.

• This reply was modified 1 year, 4 months ago by woto.

Hi g0730n,
I do not know “FEC”. What does it mean?

ok, I read
https://mischianti.org/ebyte-lora-e32-micropython-exploring-library-2/
now.

I think it is on, because the Default-Value is ON.

Hi g0730n,

thanks for answer.
I will test the function “ReceiveMessageUntil()”. Maybe it could help me.

Hello,
I would now like to switch off the FEC in the Python programm.
How can I do this?

Thanks Woto

Hello,
I now have data issued to me.
In lora_e220.py, I insert on line 636 (before data = data.decode(‘utf-8’):
print (data)

If I receive all 4s, I get the following output:
b’0212024.2.2 15:14:25 5cm’
After 4s the next output:
b’0212024.2.2 15:14:29 19cm’

If I receive every second, Data looks like this:
b’0212024.2.2 16:59:58 7cm\xf00212024.2.2 16:59:59 19cm’

After “7cm” it says \xf0. What does that mean?

• This reply was modified 1 year, 3 months ago by woto.
• This reply was modified 1 year, 3 months ago by woto.

Hello,

When I enter the following in the Thonny IDE, I get an error message:

>>> b'\xf0'.decode()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
UnicodeError: 
>>> 

I think the problem is the character \xf0.
This does not seem to be a Unicode character. Unfortunately, µPython does not allow you to specify a second parameter in the decode() function, e.g. data.decode('UTF-8','ignore').

This does not work.
But how can this be solved?

• This reply was modified 1 year, 3 months ago by woto.

Hi Renzo,
I tried it, but it does not work. I get the following error in der Thonny-IDE:

>>> b'0212024.2.2  15:26:34  3cm\xf60212024.2.2  15:26:35  22cm'.encode('utf-8','ignore').decode("utf-8")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'bytes' object has no attribute 'encode'
>>>

Hi renzo,
I think I have a solution for myself, maybe for others too.
I have created a new static method in the class LoraE220:

@staticmethod
 def _cleanData(_data):
     data = bytes(_data)
        
     ret_values = []
     ret_arr = bytearray(ret_values)
        
     for i in range(len(_data)):
         if _data[i] <= 127 :
             ret_arr.append(_data[i])
     return ret_arr

This methode is called before the decode function:

str_ret = LoRaE220._cleanData(data)

data = str_ret.decode('utf-8')
msg = data

Now the decoding function works and if I define a separator for the sender, I can separate the messages from each other.

• This reply was modified 1 year, 3 months ago by woto.