simpleRTK2B – Starter Kit LR not sending correction data

Q&A forumCategory: QuestionssimpleRTK2B – Starter Kit LR not sending correction data
Elva asked 3 weeks ago

Hello.
I ordered simpleRTK2B – Starter Kit LR last year and used a couple of times.
After that everything has laying in a box untill now.
I put it all together and started a servey-in on base and connected rover to my samsung s9 (same as last year).
But i discovered that the base is not sending anyting over xbee. GPS>XBEE not flashing.
From u-center i see fix mode change to TIME after servey-in is completed.
And of coarse the rover does not recive anything either. XBEE<GPS not flasching.
 
Any suggestions that to do?
 
//Lenny

clive1 replied 3 weeks ago

Probably need to double check the configuration.
Did you update the firmware prior to this?
Check the UBX-CFG-PRT setting for UART2 has the right baud rate, and only configured for RTCM3 IN/OUT
Check the UBX-CFG-MSG settings for the RTCM3 messages, make sure a minimum sub-set are enabled, ie 1005, 1077, 1078, 1230

2 Answers
Elva answered 3 weeks ago
  • UBX-CFG-PRT setting for UART2 has the right baud rate

What is right? It says 38400 and only RTCM3 both in and out
 

  • UBX-CFG-MSG settings for the RTCM3 messages, make sure a minimum sub-set are enabled, ie 1005, 1077, 1078, 1230

Nothing is selected. 1078 is not avalible.
I selected 1005, 1077, 1230 and now GPS>XBEE is flashing on BASE. And ROVER is reciving ‘something’
But ‘NO RTK’ is lit on ROVER. What i remember from last time i used this, ‘NO RTK’ was off.
 
//Lenny

clive1 replied 3 weeks ago

Sorry 1087 (GLONASS MSM7)
On the rover side confirm baud rate.
Confirm data reception with UBX-RXM-RTCM, should see the RTCM packets you enabled on the other side of the link.

Elva answered 3 weeks ago

It´s working. Thanks.
 
I wonder why/how the configuration has change?
Is it possible there are more that has change?
 
//Lenny

clive1 replied 3 weeks ago

Eh?

The mechanics of this haven’t changed substantially in a couple of years. Writing a new firmware will likely disturb the configurations saved previously. The use of scripts tends to obfuscate what’s actually being configured, and most thus don’t really get to review/understand the basic requirements.

FW 1.13 did get more permissive of sending RTCM3 packets, equalized the effectiveness of MSM4 vs MSM7 messages for Moving Base, and blurred the lines a little with respect to 1005 vs 4072.0

The radio transport needs to be transparent, what goes in one end comes out the other, in the same order, with not bytes added or removed. The hurdles to success are pretty low, but the data transport needs to work, and radio is often a fickle mistress.