27 lines
565 B
Python
27 lines
565 B
Python
import struct
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def checksum(data: bytes) -> bytes:
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ck_a = 0
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ck_b = 0
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for i in range(len(data)):
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ck_a = (ck_a + data[i]) & 0xFF
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ck_b = (ck_b + ck_a) & 0xFF
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return struct.pack("BB", ck_a, ck_b)
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def frame_create(msg_class: int, msg_id: int, payload: bytes) -> bytes:
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hdr = b'\xb5\x62'
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frame = struct.pack('B', msg_class)
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frame += struct.pack('B', msg_id)
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frame += struct.pack('<H', len(payload))
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frame += payload
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check = checksum(frame)
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return hdr + payload + check
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if __name__ == "__main__":
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result = frame_create(1, 2, b'Hallo')
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print(result)
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