Recover GPS-RTK2 from Connection Issues?

tomg · August 22, 2024, 3:13pm

SparkFun GPS-RTK2 u-blox ZED-F9P Connection Issues

Setup:

OS: Windows 10
Connection: USB-C via u-center

I connected the GPS-RTK2 to u-center via USB-C, and everything seemed fine initially. Then I added an OpenLog SD card reader using Qwiic, but noticed it was only writing blank files to the SD card—strange.

I tried initializing OpenLog with a sketch from the example library in Arduino IDE but got no results. I adjusted settings in u-center, especially messages to/from UART1, experimenting with various configurations based on forum advice and my growing understanding of the system. Then, I tried uploading an example sketch to write RTCM data to the SD card, along with other similar sketches.

Issues: At this point, u-center started having trouble connecting to the COM ports. Opening the menu takes a long time, where originally it popped right up. It seemed the ports were always busy, but I couldn’t find anything else using it—Arduino IDE included, though it might be holding a reference somewhere in Windows. Switching USB ports or rebooting would sometimes resolve the issue, but now I can rarely connect. When I do, the top bar shows a green handshake, but the bottom bar stays grey, and there’s no activity in the UI. u-center crashes when I attempt any action.

Additionally, even outside of device connections, u-center seems laggy. I’ve reinstalled it multiple times, removed drivers, and rebooted without improvement.

To troubleshoot further, I purchased a Serial Basic, soldered pins onto the RTCM correction pins on the GPS-RTK2 (UART2?), and connected it via USB-C using a brand new cable. It shows up as USB-Serial CH340 on COM15. I confirmed the connection with a loopback test in PuTTY, but when I connect it to the GPS-RTK2 and open u-center, I face the same “connected but no info” status. Disappointingly, I get no response from the GPS-RTK2 through the Serial Basic.

The firmware update tool also fails to connect, whether through USB-C or Serial Basic. It repeatedly tries to poll the version but eventually fails, and the update utility crashes with an exit code (2).

I have pulled line low on RST pin on GPS-RTK2 more than once, and while it does reset, it doesn’t do anything meaningful and the problems remain.

The GPS-RTK2 PPS light is blinking once every 4s. I believe in the past, it was blinking every 2s. I have not been able to find posts on PPS blinking at a frequency that is not once per s.

Summary: I’ve read countless documents and forum posts, but I’m stuck. What could I be doing wrong, and is there a way to recover from this? Any advice would be greatly appreciated. Thanks for your time.

TS-Russell · August 22, 2024, 9:53pm

Do you have any win11 machines around that you can test with to rule it out as a potential issue?

tomg · August 23, 2024, 2:17am

On Windows 11, unfortunately I get the same results.

To GPS-RTK2 cannot connect to com port
Via Serial Basic I get the connection up top, but no handshake icon on bottom bar, no action.

Thanks for the suggestion. I need to find a way to update my i9900 its ineligible

Edit: On windows 11, the lag in u-center is gone, however it is of course another machine.

tomg · September 14, 2024, 7:13pm

bumping this along

Perhaps someone can confirm to me instead that it is indeed possible to disallow through configuration communication on both uart ports to a point where the reset functionality does not bring it back to a workable state, and the board is in fact ‘bricked’ as they say and is now garbage - would just be nice to hear that you can in fact ruin these boards so I can move on.

In addition - any comment on the successful connection but no handshake activity on the lower bar. This is very common to read about online but no answers as to what causes it or how to restore settings from this state.

Thanks

sparky · September 15, 2024, 4:55pm

If I’ve got Bluetooth enabled, I will see u-center lag for 4-5 seconds when I hit the com port drop down box:

This is normal behavior in my mind. This is u-center pinging each COM port to see what is active. If Bluetooth is turned off, and those ports are gone, then u-center is very quick to display the dropdown of COM ports. This behavior doesn’t affect the ZED, and is just an artifact of the u-center interface.

Once connected to a ZED, with an antenna attached, you should begin to see all sorts of data roll by including a 1 second blink of the PPS LED. You report 4 seconds - I have never seen this, nor can I explain it.

I would start from the basics. I assume you’ve got the u-blox driver installed and can see the associated COM port. From there, I would use u-center to verify communication and the version of firmware loaded on the ZED:

Above, firmware is HPG v1.32. If you’ve gotten this far, I would do a factory reset by using the CFG-CFG command below:

Assuming you’ve got the externally attached USB to serial board on UART 1 of the ZED, it should be outputting NMEA at 38400 (once you’ve factory reset things), config shown below: