Exemple #1
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def _convert_elevation(bin_data):
	'''Convert the elevation from 15 bit binary big endian to signed int. Only
	the last 15 bit are taken from the 2 byte input.
	
	@param bin_data: 2 byte binary data.'''
	chunk_one = bin(ord(bin_data[0]))[2:]
	chunk_one = '%s%s' % ((8-len(chunk_one))*'0', chunk_one)
	chunk_one = chunk_one[1:]
	chunk_two = bin(ord(bin_data[1]))[2:]
	chunk_two = '%s%s' % ((8-len(chunk_two))*'0', chunk_two)
	bit_string = '%s%s' % (chunk_one, chunk_two)
	if bit_string.startswith('1'): # negative, build two-complement
		result = ''
		for char in bit_string:
			result = '%s%s' % (result, '1' if char == '0' else '0')
		return -(int(result, 2) + 1)
	else: # positive
		return int(bit_string, 2)
Exemple #2
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def _convert_time(data):
	'''Convert the binary time to a datetime object and return it.
	
	@param data: The binary time.'''
	bin_data = ''
	for byte in data:
		bin_chunk = bin(ord(byte))[2:]
		bin_data = '%s%s%s' % (bin_data, (8-len(bin_chunk))*'0', bin_chunk)
	year = int(bin_data[0:6], 2) + 2006
	month = int(bin_data[6:10], 2)
	day = int(bin_data[10:15], 2)
	hour = int(bin_data[15:20], 2)
	minute = int(bin_data[20:26], 2)
	second = int(bin_data[26:32], 2)
	return datetime.datetime(year, month, day, hour, minute, second)
Exemple #3
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def _convert_speed(bin_data):
	'''Convert the speed from 9 bit binary big endian to int in km/h. The input
	has the size of 2 byte, but only the first 9 bit are interpreted.
	
	@param bin_data: 2 byte binary data.'''
	return ord(bin_data[0]) + int(bin(ord(bin_data[1]))[2:3], 2)