User Manual

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Copyright (c) 2009-2013 RoboPeak Team
Copyright (c) 2013-2016 Shanghai Slamtec Co., Ltd.
Format of the data response packets
RPLIDAR uses the following data response packet structure for responding the
EXPRESS_SCAN request.
Figure 4-11 Format of a RPLIDAR Express Scan Data Response Packet
When working in express scan mode RPLIDAR will send the above data packet
cyclically to output the measurement data to host system. The packet contains 16
group of substructures called Cabin in the same format. Each Cabin is a 5-byte data
body with specific structure corresponding with the angle and distance value of two
measurement sampling data sets. Therefore, an express scan data response packet
carries 32 measurement sampling data points.
ChkSum[7:4]
sync1
ChkSum[3:0]
8
3
0
start_angle_q6[7:0]
8
0
start_angle_q6[14:8]
8
0
cabin[0]
39
0
+0
+1
+2
+3
+4
Byte
offset
sync2
8
3
0
S
7
cabin[1]
3
9
0
+9
cabin[15]
39
0
+79



8
1
0
+0
+1
+2
+3
distance1[14:7]
8
0

[3:0]
8
0
+4
distance1[6:0]



8
1
0
distance2 [14:7]
8
0
distance2[6:0]

[3:0]
3
Cabin