checksum_utils.py
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32 
33 """Utilities for calculating and checking NMEA checksums."""
34 
35 
36 def check_nmea_checksum(nmea_sentence):
37  """Calculate and compare the checksum of a NMEA string.
38 
39  Args:
40  nmea_sentence (str): The NMEA sentence to check.
41 
42  Return True if the calculated checksum of the sentence matches the one provided.
43  """
44  split_sentence = nmea_sentence.split('*')
45  if len(split_sentence) != 2:
46  # No checksum bytes were found... improperly formatted/incomplete NMEA data?
47  return False
48  transmitted_checksum = split_sentence[1].strip()
49 
50  # Remove the $ at the front
51  data_to_checksum = split_sentence[0][1:]
52  checksum = 0
53  for c in data_to_checksum:
54  checksum ^= ord(c)
55 
56  return ("%02X" % checksum) == transmitted_checksum.upper()


nmea_navsat_driver
Author(s): Eric Perko , Steven Martin
autogenerated on Mon Feb 28 2022 22:57:09