Figure 7-5 RS-232 Example Transmission
7.4.4 GPS Connection Scenarios
Depending on the user’s application, the source of the NMEA message (and PPS) can be a GPS/INS receiver or a sub-
stitute device such as a laptop or microcomputer.
There are three common connection scenarios: connecting to a sensor from a Velodyne-supplied Garmin 18x LVC GPS
receiver, connecting to it from a computer's serial port, and connecting directly from a microcomputer’s UART.
7.4.4.1 Connecting a Garmin 18x LVC GPS Receiver
As an option, Velodyne LiDAR offers a Garmin 18x LVC GPS Receiver (P/N 80-GPS18LVC) pre-configured for optimized
operation with your sensor. The receiver plugs directly into the Interface Box’s GPS port and is used to synchronize your
sensor's timestamp with precision GPS time. The signals from the Garmin receiver will be similar to those shown in
where the signal is normally low and zeros are represented by the high voltage.
Figure 7-6 Garmin GPRMC Message
7.4.4.2 Connecting to a computer's serial port
In some situations, you may wish to source NMEA messages from a computer instead of a GPS receiver.
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VLP-16 User Manual