search

CBrunsch / scambus

Scambus is a python based wireless M-Bus scanner and dissector
MIT License
31 stars 16 forks source link

frame length field does not match length #5

Open tca22 opened 5 years ago

tca22 commented 5 years ago

I try to decode with ./reader.py -v -t '764421042003377025071C5F722003377021042507180060054F9E79056282DB137F36127732F287DC99463D448F7AE638B54250D4D49255AF4CBF70FC5918CEBCEB3A9942507D02A7C7F8F11D4130F6C9C5FB4E48CE8B88E7381055B17F31C960B83F2EE219CD0E7200CA9ECA2D37CE3735AEAF7DAFCE9310BD54BD4D81CFDEC7153C5E600AFB80' but get an WARNING: frame length field does not match effective frame length! Decoding might be unreliable. Check your input. frame[0]: 118 len(frame)-1: 135 error.

I wonder if this could be an issue with reader.py instead? - When the same raw-message is parsed through another tool (FHEM, 36_WMBUS.pm), it's processed fine, without error. Is this something you could have a look at?

Thanks!

tca22 commented 5 years ago

Well, it's basically an encoded message, so I had to add the AES key to reader.py. However, the issue remains. Any thoughts?

bdkacz commented 5 years ago

I have simmilar problem - I read data using rtl_sdr and my frame is 4e440106289675010507b2a57a37004085fa090db28a90c7e15c0550d85d7ef44015708f464f7f7040512db99052a9167bf47b63471e95a7e94b95708984c28e0935d6ef1928234ed4f3ed67cac6491bd9f0ffa8901b1e76c031e7 - it is AES encoded,but after add key I have the same problem

doxus commented 2 years ago

From what i found the data needs to have CRCs stripped form data an header