Data Sheet

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 Type code
：
Start scan type code is 0x81
；
 Response content
：
Scan data, see data protocol for details.
DATA PROTOCOL
After the system starts scanning, the scanned data is output in the subsequent messages.
The data protocol is sent to the external device in hexadecimal to the serial port according
to the following data structure.
LSB
MSB
LSB
MSB
LSB
MSB
LSB
MSB
LSB
MSB
LSB
MSB
LSB
MSB
‥‥
PH
CT
FSA
LSA
CS
S1
S2
‥‥
LS
Byte offset
0
2
4
6
8
10
12
FIG 3 SCAN COMMAND RESPONSE CONTENT DATA STRUCTURE
CHART 2 SCAN COMMAND DESCRIPTIONS
Item
Name
Description
PH(2B)
Packet
header
The length is 2B, fixed at 0x55AA, with the low position in the
front and the high position in the back.
CT(1B)
Packet type
Indicates the type of the current packet; 0x00: Point cloud
packet 0x01: Start packet
LSN(1B)
Number of
samples
Indicates the number of sampling points contained in the
current packet; there is only one starting point in the starting
packet, and the value is 1.
FSA(2B)
Starting angle
Angle data corresponding to the first sample point in the
sampled data
LSA(2B)
End angle
Angle data corresponding to the last sample point in the
sampled data
CS(2B)
Check code
The current data packet check code, using double-byte XOR to
verify the current data packet
Si(2B)
Sampled data
The sampling data of the system test is the distance data of the
sampling point, and the interference flag is also integrated in
the LSB of the Si node.
 Start bit analysis：
When CT=1, that means the packet is a start data packet. In the packet , you can see LSN
= 1(the number of Si is 1). The specific values of distance and angle are as follows.
 Distance resolution:
Distance calculation formula
：
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