Time Synchronization; Gps Time Synchronization; The Use Of Gps For Time Synchronization - RoboSense LiDAR RS-Ruby Plus User Manual

4.6 Time Synchronization

RS-Ruby Plus supports GPS+PPS and PTP time synchronization methods.Users can use the
RS-Ruby Plus Web Interface to set. (Please refer to Appendix A.2)
RS-Ruby Plus can be connected to an external GPS module and can synchronize the sensor system
time with the time provided by the GPS.

4.6.1 GPS Time Synchronization

The GPS module continuously sends GPRMC message and PPS synchronization pulse signals to
the sensor. The PPS synchronization pulse width is from 20ms to 200ms, and the GPRMC message
must be sent within 500ms after the rising edge of the PPS synchronization pulse.

4.6.2 The Use of GPS for Time Synchronization

The GPS_REC interface in the Interface Box of the RS-Ruby Plus follows the RS232 level standard,
as shown in the table below:
Level
Receive the RS232 serial data
RS232
output by the GPS module
Note 1: The GPS_REC interface in the RS-Ruby Plus Interface Box is the JST S12B-J11DK-TXR connector, and the pin
definition is as shown in Figure 2-4.
The external GPS module needs to set the serial output baud rate to 9600bps, 8 bits, no parity, 1
stop bit. RS-Ruby Plus only accepts the GPRMC sentence sent by the GPS module. The standard
structure of the GPRMC sentence is as follows:
$GPRMC,<1>,<2>,<3>,<4>,<5>,<6>,<7>,<8>,<9>,<10>,<11>,<12>*hh
According to GPRMC message, synchronize the part of second
Reset part of sub-second
Figure 4-3 GPS Time Synchronization Timing Diagram
Table 4-3 GPS Receive Pin Definition
Receive Pin Definition
GPS GPRMC
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RS-Ruby Plus User Manual
GPS PPS
Receive the positive synchronization pulse signal
output by the GPS module, the level is required
to be 3.0V~15.0V