Hi guys,
I’m trying to get a Holybro M9N Dronecan GPS to work with a Matek H743 Slim v3 running Rover 4.5.2. However even when the GPS “3d fix” LED is solid blue (on the M9N unit itself) it still says “GPS: No Fix” in Mission Planner.
gpsstatus = 1
satcount = 0
Shouldn’t satcount be more than 0 if I have a 3d fix?
Any ideas what could be wrong here?
I think I’ve got this GPS unit to work before (on the bench) but not 100% sure. So could of course be defective.
Best Regards,
Andreas
Maybe a configuration error?
Please post a parameter file.
2024-05-14 23:18:09 : GPS 1: specified as DroneCAN1-125
2024-05-14 23:18:02 : EKF3 waiting for GPS config data
2024-05-14 23:18:02 : EKF3 waiting for GPS config data
2024-05-14 23:17:52 : EKF3 waiting for GPS config data
2024-05-14 23:17:52 : EKF3 waiting for GPS config data
2024-05-14 23:17:44 : PreArm: Compass not calibrated
2024-05-14 23:17:44 : PreArm: 3D Accel calibration needed
2024-05-14 23:17:41 : EKF3 waiting for GPS config data
2024-05-14 23:17:41 : EKF3 waiting for GPS config data
2024-05-14 23:17:31 : EKF3 waiting for GPS config data
2024-05-14 23:17:31 : EKF3 waiting for GPS config data
2024-05-14 23:17:21 : EKF3 waiting for GPS config data
2024-05-14 23:17:21 : EKF3 waiting for GPS config data
2024-05-14 23:17:13 : PreArm: Compass not calibrated
2024-05-14 23:17:13 : PreArm: 3D Accel calibration needed
2024-05-14 23:17:11 : EKF3 waiting for GPS config data
2024-05-14 23:17:11 : EKF3 waiting for GPS config data
2024-05-14 23:17:01 : EKF3 waiting for GPS config data
2024-05-14 23:17:01 : EKF3 waiting for GPS config data
2024-05-14 23:16:51 : EKF3 waiting for GPS config data
2024-05-14 23:16:51 : EKF3 waiting for GPS config data
2024-05-14 23:16:42 : PreArm: Compass not calibrated
2024-05-14 23:16:42 : PreArm: 3D Accel calibration needed
2024-05-14 23:16:41 : EKF3 waiting for GPS config data
2024-05-14 23:16:41 : EKF3 waiting for GPS config data
2024-05-14 23:16:31 : EKF3 waiting for GPS config data
2024-05-14 23:16:31 : EKF3 waiting for GPS config data
2024-05-14 23:16:21 : EKF3 waiting for GPS config data
2024-05-14 23:16:21 : EKF3 waiting for GPS config data
2024-05-14 23:16:11 : EKF3 waiting for GPS config data
2024-05-14 23:16:11 : EKF3 waiting for GPS config data
2024-05-14 23:16:11 : PreArm: Compass not calibrated
2024-05-14 23:16:11 : PreArm: 3D Accel calibration needed
2024-05-14 23:16:09 : IMU0: fast sampling enabled 2.0kHz
2024-05-14 23:16:09 : RCOut: PWM:1-13
2024-05-14 23:16:09 : MatekH743 003C0049 31315103 39353837
2024-05-14 23:16:09 : ChibiOS: 6a85082c
2024-05-14 23:16:09 : ArduRover V4.5.2 (291be848)
2024-05-14 23:16:08 : IMU0: fast sampling enabled 2.0kHz
2024-05-14 23:16:08 : RCOut: PWM:1-13
2024-05-14 23:16:08 : MatekH743 003C0049 31315103 39353837
2024-05-14 23:16:08 : ChibiOS: 6a85082c
2024-05-14 23:16:08 : ArduRover V4.5.2 (291be848)
2024-05-14 23:16:08 : IMU0: fast sampling enabled 2.0kHz
2024-05-14 23:16:08 : RCOut: PWM:1-13
2024-05-14 23:16:08 : MatekH743 003C0049 31315103 39353837
2024-05-14 23:16:08 : ChibiOS: 6a85082c
2024-05-14 23:16:08 : ArduRover V4.5.2 (291be848)
2024-05-14 23:16:05 : EKF3 waiting for GPS config data
2024-05-14 23:16:05 : EKF3 waiting for GPS config data
I’ve also tried to set GPS_AUTO_CONFIG to 2 (DroneCAN option) but same result.
As soon as the blue 3D Fix LED goes solid blue, the status in mission planner changes from No GPS to No Fix. But satcount is still 0.
This is how it looks in the CAN inspector once the Fix LED is lit on the GPS unit. Either the GPS is defective or I still have something wrong in my config. Just cannot find what it is.
I’m giving up on this and have just ordered a new identical module. Will be interesting to see if it works or not 
I’m a bit confused that it IDs as HolybroG4_GPS, I thought that was the F9P. Did you flash the firmware of your GPS?
The first folder should be for the F9P, the second one for the M8N and M9N I think.
EDIT: Here I mean.
No, I haven’t flashed the fw. I have no idea how to do that even. Can you please elaborate what makes you think that?
Oh, G4 is another Holybro product perhaps. Hmm well then that’s confusing.
In CAN Inspector it identifies as HolybroG4_GPS, which I think is the Holybro CAN GPS with an F9P chip, not your model with an M9N chip. That should identify as HolybroGPS (likely, maybe something else, but not HolybroG4_GPS). On the other hand, you haven’t flashed anything so why would it show the wrong ID.
You can update the firmware via Mission Planner: DroneCAN FW Upgrade | Holybro Docs
That’s all pure conjecture though, I could be completely wrong. I personally would try flashing the HolybroGPS firmware, but I don’t want you to brick your GPS module so I won’t advise you to do so. If you’ve already ordered a replacement part it will be interesting what it shows up as in CAN Inspector.
