Ublox EVK-M101 User Manual page 25

EVK-M101, EVK-M101C - User guide
The configuration will generate four ports as shown in the example in Figure 15 and the third port
can be used for UART communication with the receiver.
Figure 15: EVK-M101/C communication ports in Linux environment
EVK-M101/C does not work properly when connected to a GNSS simulator
When using EVK-M101/C together with a GNSS simulator, please pay attention to proper handling
of the EVK. A GNSS receiver is designed for real-life use (i.e. time is always moving forward). When
using a GNSS simulator scenarios, the scenario time can be in the past resulting in the receiver to
jump backwards in time. This can have serious side effects on the performance of GNSS receivers.
The solution is to configure the GPS week rollover value to a week number preceding the date in
GNSS simulator scenario. For example, setting the GPS week number to 1200 (corresponding to Jan
2003) allows running simulator scenarios taking place after this date. Please refer to Figure 16 for
how to set the GPS week number with u-center 2 GNSS evaluation tool. In addition, always issue a
cold start command before every simulator test to avoid receiver confusion due to the time jumps.
Figure 16: Setting GPS week number with u-center 2 GNSS evaluation tool
UBX-21003949 - R04 9 Troubleshooting Page 25 of 30
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