Hi Rob,
- Attaching Images to Forum Posts
Take a screenshot. Save it to your computer. Use the “Upload attachment” tab to attach the image to your post. You can drag and drop, or “Add files” through the file explorer. “Place inline” will insert the image - or a link to it - part-way through your post. Without place inline, the image is attached at the end of your post. Some images display fully, some just appear as links, I’ve been using the Forum for years and I still haven’t figured out how to always make the image display in the post!
- Antennas
Please make sure you are using a good quality dual-band antenna - with a clear view of the sky. Single-band antennas and/or a partial sky-view can cause all kinds of problems and prevent RTK from working properly.
- Restoring Default Configuration
You can reset the GNSS module back to its default (factory) configuration via u-center. Open Messages View and navigate to UBX-CFG-CFG. Select “Revert to default configuration” and click “Send”. Then “Save current configuration” and “Send”.
This is a good idea if you’re not sure what state your module is in.
- TIME solution
As I understand it, you want to get the F9T into a TIME-only solution - like you do with your F9P for RTK NTRIP.
If you are completely confident that you have an accurate ECEF (or LAT/LON/HEIGHT) position for your antenna, then, yes, you should be able to put the F9T into that mode like you do with the F9P. If you’re not completely confident about the position, I’d recommend doing a Survey-In first.
With the F9P, you configure the Time mode using UBX-CFG-TMODE3 (Class 0x06, ID 0x71).
u-center (22.07) supports only UBX-CFG-TMODE (Class 0x06, ID 0x1D) and UBX-CFG-TMODE3 (Class 0x06, ID 0x71).
According to the F9 TIM 2.20 Interface Description, the F9T only supports UBX-CFG-TMODE2 (Class 0x06, ID 0x3D). Not UBX-CFG-TMODE or UBX-CFG-TMODE3.
So, it is my belief that you will need to do the configuration using the UBX-CFG-VALSET message instead.
I’d recommend resetting to the default configuration first. Then:
In Messages View, navigate to UBX-CFG-VALSET. You need to “build up” several KEY IDs and then send them all in one go.
To start a survey-in, select:
Group CFG-TMODE, Key CFG-TMODE-MODE, “Add to list”. Then highlight the line that just appeared in the Configuration Items and select “1 - SURVEY_IN” as the Value.
Then Add:
Group CFG-TMODE, Key CFG-TMODE-SVIN_MIN_DUR with a value of 60 (seconds)
Group CFG-TMODE, Key CFG-TMODE-SVIN_ACC_LIMIT with a value of 50000 (* 0.1mm = 5.0m)
Click “Send” to start the survey-in.
Navigate to UBX-NAV-SVIN. Keep clicking “Poll” to watch the survey-in complete. It will complete when at least 60 seconds have passed and the accuracy is better then 5.0m.
All being well, it should then go into TIME mode. You can read off the ECEF position and use that with CFG-TMODE-MODE “2 - FIXED”.
For better accuracy, select 600 seconds and 10000 (* 0.1mm) = 1.0m.
- Enabling Periodic Messages
To save all that Poll-clicking, you can tell the module to output selected messages periodically.
Navigate to UBX-CFG-MSG.
Select 01-07 NAV-PVT and select “USB” (assuming you are connected via USB, not UART) to set the rate to 1Hz. Click “Send”. The module will now output UBX-NAV-PVT every second. In TIME mode, the position won’t change.
Likewise, you can enable 01-3B NAV-SVIN at 1Hz.
Navigate to UBX-NAV-SVIN to see the status without needing to click Poll.
I hope this gets you going,
Paul
