27
Table 5.4 Configuration Package Example
Info
Content
Config
Length
(
byte
)
Header
0xAA, 0x00, 0xFF, 0x11, 0x22, 0x22,
0xAA, 0xAA
8
Motor Speed
1200 rpm
0x04, 0xB0
2
Lidar IP (IP_SRC) 192.168.1.105
0xC0, 0xA8, 0x01, 0x69
4
Computer IP
(IP_DEST)
192.168.1.225
0xC0, 0xA8, 0x01, 0xE1
4
Data Port (port1)
6688
0x1A20
2
Device Port
(port2
)
8899
0x22C3
2
Lidar Rotation /
Stationary
Rotation
0x0000
2
Reserved
Reserved
0x00
1180
Tail
0x0F, 0xF0
2
When using this protocol to configure the device, byte-level or section-level addressing
and writing are not allowed, and the entire list must be written completely. After the list
is written, the corresponding function will be updated and take effect immediately.
6. Time Synchronization
There are two ways to synchronize the Lidar and external equipment: GPS
synchronization and external PPS synchronization. If there is no external
synchronization input, the Lidar internally generates timing information. The absolute
accurate time of the point cloud data is obtained by adding the 4-byte timestamp
(accurate to microsecond) of the data packet and the 6-byte UTC (accurate to second)
of the device packet.
6.1 GPS Synchronization
When GPS synchronization is employed, the Lidar will start timing in microseconds
after receiving the PPS second pulse, and the time value will be output as the timestamp
of the data packet. The Lidar extracts UTC information from the $GPRMC of the GPS
as the UTC (accurate to the second) output.
The GPS equipment is time-synchronized to mark and calculate the precise emission
and data measurement time of each laser. The precise time of the Lidar point cloud can
be matched with the pitch, roll, yaw, latitude, longitude and height of the GPS/inertial
measurement system.
The default serial configuration baud rate of the GPS data output received by the Lidar