NCS540 (N540X-16Z4G8Q2C-A) often fails to enter Time fix mode

[alansung1]

Dear All,

Recently I was doing NCS540 (N540X-16Z4G8Q2C-A) as a GM test. After 2 days of Survey-in, it could not enter Time-fix mode. There are very few instructions on setting GNSS in the file. N540X-16Z4G8Q2C-A looks like The U-Blox M8T module is used. Can anyone provide information on how to configure the GNSS module through the CLI?

[tkarnani]

Hi @alansung1 ,

here is the configuration guide

https://www.cisco.com/c/en/us/td/docs/iosxr/ncs5xx/timing-and-sync/71x/b-network-sync-71x-ncs540/b-network-sync-71x-ncs540_chapter_0101.html

Configuration Example
This section describes how you can configure GNSS for a router.

/* Enable the GNSS receiver and enter the gnss-receiver submode */

RP/0/RP0/CPU0(config)# gnss-receiver 0 location 
RP/0/RP0/CPU0(config-gnss)# no shutdown
RP/0/RP0/CPU0(config-gnss)# frequency synchronization
RP/0/RP0/CPU0(config-gnss-freqsync)# selection input
RP/0/RP0/CPU0(config-gnss-freqsync)# commit

Optional Configuration Example

RP/0/RP0/CPU0(config)# gnss-receiver 0 location 
RP/0/RP0/CPU0(config-gnss)# anti-jam disable
RP/0/RP0/CPU0(config-gnss)# constellation GPS
RP/0/RP0/CPU0(config-gnss)# snr threshold 10
RP/0/RP0/CPU0(config-gnss)# frequency synchronization
RP/0/RP0/CPU0(config-gnss-freqsync)# selection input
RP/0/RP0/CPU0(config-gnss-freqsync)# priority 5
RP/0/RP0/CPU0(config-gnss-freqsync)# wait-to-restore 180
    

[alansung1]

In addition to the above configuration examples, are there other related documents? Such as command function and parameter description, and simple troubleshooting.

[alansung1]

The manual of NCS540 is not very complete, please refer to the link above, there should be some problems with the sample at the end of the manual. Hope to have more detailed documents.

-------------------Configure the Global Navigation Satellite System----------

The following is the output of the show gnss-receiver command on the router models - N540-24Z8Q2C-SYS, N540-28Z4C-SYS, N540-ACC-SYS, and N540X-ACC-SYS. <<< Over determined clock mode ( could be Trimble module)

RP/0/RP0/CPU0:R6#sh gnss-receiver 
Fri Jan 17 07:27:34.804 UTC
GNSS-receiver 0 location 0/RP0/CPU0
    Status: Available, Up
    Position: 12:56.18 N 77:41.77 E 0.823km
    Time: 2020:01:17 07:31:41 (UTC offset: 0s)
    Locked at: 2020:01:15 17:15:28
    Firmware version: TIM 1.10   <<<< U-Blox M8T firmware version - the sample is not match