37 lines
959 B
Python
37 lines
959 B
Python
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import struct
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class AFrame:
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def __init__(self, data: bytes):
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self.valid = False
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self.data_id = 0
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self.data_len = 0
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self.payload = b""
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# A帧最小长度: 4+4+4+4+4+4 + 8 + 2 = 34
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if len(data) < 34:
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return
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try:
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# 大端解包
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magic, dlen, dir_, data_id, ptype, sat = struct.unpack('>IIIIII', data[:24])
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payload = data[24:-2]
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tail = data[-2:]
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if magic != 0xEB90EB90 or tail != 0x4C3A.to_bytes(2, 'big'):
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return
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self.valid = True
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self.data_id = data_id
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self.data_len = dlen
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self.payload = payload
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except:
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pass
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def get_doubles(self):
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doubles = []
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buf = self.payload
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while len(buf) >= 8:
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d = struct.unpack('>d', buf[:8])[0]
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doubles.append(d)
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buf = buf[8:]
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return doubles
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