diff options
Diffstat (limited to 'glucometerutils/support/lifescan.py')
| -rw-r--r-- | glucometerutils/support/lifescan.py | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/glucometerutils/support/lifescan.py b/glucometerutils/support/lifescan.py index 19155d4..9340e49 100644 --- a/glucometerutils/support/lifescan.py +++ b/glucometerutils/support/lifescan.py @@ -8,22 +8,25 @@ from glucometerutils import exceptions class MissingChecksum(exceptions.InvalidResponse): """The response misses the expected 4-digits checksum.""" + def __init__(self, response): super(MissingChecksum, self).__init__( - 'Response is missing checksum: %s' % response) + "Response is missing checksum: %s" % response + ) class InvalidSerialNumber(exceptions.Error): """The serial number is not as expected.""" + def __init__(self, serial_number): super(InvalidSerialNumber, self).__init__( - 'Serial number %s is invalid.' % serial_number) + "Serial number %s is invalid." % serial_number + ) class MalformedCommand(exceptions.InvalidResponse): def __init__(self, message): - super(MalformedCommand, self).__init__( - 'Malformed command: %s' % message) + super(MalformedCommand, self).__init__("Malformed command: %s" % message) def crc_ccitt(data): @@ -39,13 +42,13 @@ def crc_ccitt(data): This function uses the non-default 0xFFFF seed as used by multiple LifeScan meters. """ - crc = 0xffff + crc = 0xFFFF for byte in data: - crc = (crc >> 8) & 0xffff | (crc << 8) & 0xffff + crc = (crc >> 8) & 0xFFFF | (crc << 8) & 0xFFFF crc ^= byte - crc ^= (crc & 0xff) >> 4 - crc ^= (((crc << 8) & 0xffff) << 4) & 0xffff - crc ^= (crc & 0xff) << 5 + crc ^= (crc & 0xFF) >> 4 + crc ^= (((crc << 8) & 0xFFFF) << 4) & 0xFFFF + crc ^= (crc & 0xFF) << 5 - return crc & 0xffff + return crc & 0xFFFF |