Please please pleasehi,
i'am a beta tester to a one app for fotogrammetry, and i have a possible solution to downgrade the rc and the drone.
for third party app actually is only possible to install in the drone and rc a developer firmware. then you might install on the drone and rc the developer version of the firmware and then later return to the version you want , I prefer the 1.1.9 instead of 1.2.6 .
if we want , i write the guide .
Phantom 3 guide to downgrade
1) Downgrade the transmitter
In order to get the new firmware to install on the transmitter, you will have to downgrade the transmitter with this tool " https://www.dropbox.com/s/wapuxv3b5e94pny/gs_ofdm.bin?dl=1 ". Please follow the same instructions for updating, except using the gs_ofdm.bin file in the root directory of the USB drive instead of the firmware bin file.
This process will take up to 60 seconds to start, and about 2 minutes to complete. Power off the RC, remove the USB key, and follow the standard firmware update procedure from here.
2) Update the transmitter and Drone
You can find the SDK supported firmware here " https://www.dropbox.com/s/375t56kblxmiqw0/P3X_FW_V01.01.1003.bin?dl=1 ". This will install Phantom 3 firmware v01.01.1003.
Please follow the same set of instructions as detailed on the normal firmware install page: http://download.dji-innovations.com/downloads/phantom_3/en/How_to_Update_Firmware_en.pdf
3) now install the firmware if you want
So back to the unanswered question. Do we have a firmware programmer in the house? Or Maybe a DJI engineer who could post a reset?You cannot install the dev firmware if you've done any updating of the firmware on the Phantom. This why there was a need to downgrade. Number 2 only contains information on _updating_.
This is probably what jacky just encountered.