Help! Gremlin Femto F3 Firmware Problem

[olingoudey]

Hello FliteTest Forums,

It's already been a journey to the place I'm at now in building a Gremlin. I realize now that I've been in a little bit over my head starting with a Gremlin.

I'm running into a few problems that I would love some help help fixing. Fixing one major problem might help me solving the next. This is my second attempt at building a Gremlin, so any help would be greatly appreciated.

The first problem is with the firmware of the Femto F3 flight controller. The board does not function correctly after attempts to flash firmware. A red light flashes every second, it's not possible to spin motors with BetaFlight, and the receiver and transmitter do not connect, suggesting the receiver is not properly powered. I'm worried that the FC might be bricked, but it is soldered together properly, and I have only tried flashing the SPRACINGF3EVO firmware, so I don't know why.

I've tried many times to wipe the firmware clean, and flash the right one (3.4.1 - SPRACINGF3EVO). I don't know what I'm doing wrong: First I short the boot pads, and I keep them connected because it's unclear at what point exactly I need to have them jumped. At this point I plug the FC into BetaFlight, and I see that the FC is in DFU mode. Before flashing the firmware, I successfully ran the Zadig application that the FC Manual recommends. I've experimented with this entire flashing process, changed settings in BetaFlight before flashing, all with the same result.

Anyway, thanks for taking the time to read this, I can't wait to get this working. If you have any ideas as to what might be causing this, I'd love some input.

 

[ElectriSean]

The hard part is getting it into DFU mode, if you're at that point the drivers are fine and you should be able to flash. Make sure that you have the "Full chip erase" option checked. After reconnecting you should be able to see the 3D model move as you move the FC around. Once you're at this point, you're half way there.

At this point I get my receiver connected, bound and adjust the radio endpoints and subtrim. You didn't say what receiver you're trying to use, so if you can post some more information and some pictures of your connections we can help you through it

 

[olingoudey]

Great! Thanks for the response.

We got it in DFU mode for flashing it, with these settings: After we flash the new firmware the gyro works perfectly, but the motors do not respond and we don't get signal from the receiver. (Although we were having that last problem before the firmware got screwed up, although before the bars with the channel inputs were empty, now they are stuck at halfway).

We have the boot pads shorted when we plug in the USB through when we flash it. Here's a screenshot of betaflight just before we flash:

https://imgur.com/liL83yR

These are our connections: The receiver is the FLYSKY X6B, plugged into the port labelled iBUS.

Thank you so much for your help, hope we can fix this!

 

[ElectriSean]

Connections look good, in the ports tab make sure that SerialRX is enabled on UART3, and in the configuration tab set the receiver mode to serial and the serial provider to IBUS.

 

[Userofmuchtape&glue]

Nice clean soldering too!

 

[olingoudey]

Connections look good, in the ports tab make sure that SerialRX is enabled on UART3, and in the configuration tab set the receiver mode to serial and the serial provider to IBUS.

Good news!

After getting a response from Emax support, we tried flashing the 3.0.1 firmware version and the constant flashing red light has stopped! Also, we are not getting the 5 really short flashes.

The remaining problem is that when we switch to iBUS from the default option, then save and reboot, the setting switches back from the default option, so the setting is not applying for some reason.

Here are some images of the settings currently:

https://imgur.com/qEqiAlT

(album isn't working, so here's the link: imgur.com/a/qEqiAlT )

I appreciate the help, it feels really good to make progress on this again.

Nice clean soldering too!

Thanks! That was pretty fun, although the board is insanely small!

 

[ElectriSean]

Good news!

After getting a response from Emax support, we tried flashing the 3.0.1 firmware version and the constant flashing red light has stopped! Also, we are not getting the 5 really short flashes.

The remaining problem is that when we switch to iBUS from the default option, then save and reboot, the setting switches back from the default option, so the setting is not applying for some reason.

Make sure you set up the ports tab, then save and reboot before setting up the configuration tab. If that doesn't work, it may be because there are some conflicts between the older firmware and the new versions of the configurator, which is why we always recommend using the latest versions of each. If you can't make the 3.4.x firmware work, you may have to get a hold of an older version of the configurator.

 

[olingoudey]

Make sure you set up the ports tab, then save and reboot before setting up the configuration tab. If that doesn't work, it may be because there are some conflicts between the older firmware and the new versions of the configurator, which is why we always recommend using the latest versions of each. If you can't make the 3.4.x firmware work, you may have to get a hold of an older version of the configurator.

Alright, thanks! We tried Betaflight Configurator version 10.0.0 and the IBUS setting stays after saving and rebooting. The motors spin up properly, and the FPV camera is transmitting perfectly! It's great to have it working better.

This leaves only one remaining problem: the empty receiver info in the Receiver page of the Configurator. Here's an image of what I mean:

I believe this is the correct channel map, and the serial output mode of the transmitter (FS-i6x) is set to IBUS, and the IBUS setup (not sure what this is) is on channel one.

Thanks again for your help, it's looking like there's light at the end of the tunnel!

 

[ElectriSean]

That receiver tab problem is yet another configurator/firmware conflict. To use a version as old as 3.0.x I think you'll have to go back even further with the configurator, back to the chrome app days.