Changing P3P from CE to FCC. Is it possible?

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Hey guys.
Im new to this forum and did a quick search on the topic of changing my p3p from CE mode to FCC mode. I tried several things,all to no avail. Does anyone know if this is still possible and if so how??
 
Just out of interest ... my P3P is CE but easily runs 2km urban and more rural ...

What are you getting ?

Nigel
 
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Im new to this forum and did a quick search on the topic of changing my p3p from CE mode to FCC mode. I tried several things,all to no avail.

What exactly did you tried?

Does anyone know if this is still possible?

Why "still possible"?
It can be done, but it's not easy.

and if so how??

There is no one-click script or pre-modified firmware available, if that's what you're asking for.

It is known how the OFDM board and the RC drives the power. It is known that there are differences between how it's done with Texas Instruments transciever vs. the Artosyn one.
The functions in proper firmware modules which send SPI commands to the transciever to set attenuation level are known.

If you understand what I wrote, then you should be able to do this. Otherwise - no, there's no way.
 
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What exactly did you tried?



Why "still possible"?
It can be done, but it's not easy.



There is no one-click script or pre-modified firmware available, if that's what you're asking for.

It is known how the OFDM board and the RC drives the power. It is known that there are differences between how it's done with Texas Instruments transciever vs. the Artosyn one.
The functions in proper firmware modules which send SPI commands to the transciever to set attenuation level are known.

If you understand what I wrote, then you should be able to do this. Otherwise - no, there's no way.

I tried the .DJI.configs file copy and paste to the DJI app. Im very new to Phantom drones. Realised very quickly that it wasnt possible to do it this way. I have got around 2.2Kms in Urban depending on Interference and conditions and would easily get more then that in a more open area. Just wondered if there is a relatively simple way to get to FCC mode without it costing hundreds. I have Ordered some parabolic range extenders so will see how they go. Thanks for your input guys
 
Just a quick update here guys. I bought the parabolic range extenders for my p3 pro. Tested it out today. Got 5km and Still had full signal connection. Didnt drop out at all. However.... I almost lost it on the way back as i was bringing it back home with a head wind. It force landed, but only 250 metres away. All in all the parabolics work so well. More then doubled the range. I was out in the open at the same spot that i recently got 2400 metres and then lost signal.. Very Impressed with the Improvement
 
Just a quick update here guys. I bought the parabolic range extenders for my p3 pro. Tested it out today. Got 5km and Still had full signal connection. Didnt drop out at all. However.... I almost lost it on the way back as i was bringing it back home with a head wind. It force landed, but only 250 metres away. All in all the parabolics work so well. More then doubled the range. I was out in the open at the same spot that i recently got 2400 metres and then lost signal.. Very Impressed with the Improvement
For what it's worth ... when you use this version of DJI Go, you fly in FCC mode:

DJI GO 3.1.18 FCC (English)
 
For what it's worth ... when you use this version of DJI Go, you fly in FCC mode:

DJI GO 3.1.18 FCC (English)

How can a Go App alter FW settings ? The FCC / CE is set by FW and the GPS location. To cheat that - there is a hack to alter the code line in the FW ... which basically Magic Power and Icarus do along with adding Telnet and allowing rollback to factory setting.

Nigel
 
How can a Go App alter FW settings ?

It is possible. Both the OFDM board and RC main board can get remote instruction to configure RF power.
But this is a complicated matter. Noone I know can understand all the quirks of sending such a packet.
And looks like noone is willing to spend more time into researching this.

The FCC / CE is set by FW and the GPS location. To cheat that - there is a hack to alter the code line in the FW ...

I did not heard about hacking Ph3 Pro/Adv to FCC by changing firmware. It is possible - by just changing all places where transceiver attenuation is set. It is a very brute-force method though.

While we know that FCC/CE is selected by GPS, and we know the mobile device is not required for the selection to work - we don't know which module within the drone selects the power mode and orders the rest of the drone to enter that mode.

which basically Magic Power and Icarus do along with adding Telnet and allowing rollback to factory setting.

You seem to talk about Phantom 3 Std. Lightbridge is completely different.
 
It is possible. Both the OFDM board and RC main board can get remote instruction to configure RF power.
But this is a complicated matter. Noone I know can understand all the quirks of sending such a packet.
And looks like noone is willing to spend more time into researching this.

As far as I know - it all refers back to FW .. and is why many 'hacks' in the past needed to be re-made each time powering up.

I did not heard about hacking Ph3 Pro/Adv to FCC by changing firmware. It is possible - by just changing all places where transceiver attenuation is set. It is a very brute-force method though.

While we know that FCC/CE is selected by GPS, and we know the mobile device is not required for the selection to work - we don't know which module within the drone selects the power mode and orders the rest of the drone to enter that mode.

Again as I was told - it comes down again to modifying control command set in FW.

I'm no hacker .. well actually in old days mmmmmmmm ... but with this piece of gear ? I leave well alone as having had boards blow just from FW change - I am reluctant to go near FW again.

You seem to talk about Phantom 3 Std. Lightbridge is completely different.

I am well aware of the difference as an owner of both ... BUT both function on similar FW ... majority of the code incl. FCC / CE from GPS data is as I understand same.

I agree that MP and Icarus are for P3S and for the 2.4Ghz Video set.

If I wanted to boost P3A or P3P ... to be quite honest - I would use a couple of external boosters and remove all the hassle / question of where / what does what etc. But as I'm a CE user and I already get over 2km anyway ... and if I want more I have the double parabola ... I can leave well alone.

I had 5km with my P3S ... so my mod'g days of P3 is satisfied.

Nigel
 
You seem to talk about Phantom 3 Std. Lightbridge is completely different.

I am well aware of the difference as an owner of both ... BUT both function on similar FW ... majority of the code incl. FCC / CE from GPS data is as I understand same.

Your statement about similar FW is correct. Though you need to know what does "similar" really mean in this context.

The Phantom 3 firmware (for any Ph3) is a pack of individual firmware modules. Each module contains programming for a specific chip, and there are a lot of programmable chips within the drone. The individual modules are explained here:
DJI Firmwares · o-gs/dji-firmware-tools Wiki · GitHub

The Ph3 Pro and Ph3 Adv have almomst identical firmware - only one of the modules is different (m0100).
For Ph3 Std, the Flight Controller firmware is identical to Pro (m0305, m0306), and some modules are similar. But the transceiver control modules are completely different. The FCC/CE selection is made in a different way.
 
Psycho Andy, I've seen another thread you created about that. Let me summarize:

1. FCC vs CE in the transceiver

There are two different implementations of lightbridge link used in Ph3 Pro/Adv:
- Analog Devices transciever + Altera FPGA - used in OFDM board v1 for the drone part and GL300a/b radio controller
- Artosyn transciever + Artosyn dedicated processing chip - used in OFDM v2 and GL300c
Sources:
o-gs/dji-firmware-tools
o-gs/dji-firmware-tools

While the Artosyn transciever is suspiciously similar to AD, there are also differences:
- both chips use the same SPI interface to configure internal options
- both have internal registers, of which one stores the transciever attenuation
- some of the registers have different addresses in each chip, and the attenuation value represents a different powe level in both chips
Source - reverse engineering firmware modules using symbols from here:
o-gs/dji-firmware-tools

2. FCC vs CE in the lightbridge control

The lightbridge pipeline is controlled by STM micro-controller, on both the OFDM board and GL300 main board. The STM uCs have firmware:
- m1400 for the controller within GL300
- m0900 for the controller within aircraft
These uCs are sending SPI instructions to transceivers, including one to configure attenuation, based on packets they receive from other parts of the drone. The packets are in so-called DUML format.
Source:
o-gs/dji-firmware-tools

3. FCC vs CE in the DUML

From FW analysis, it is known that there are DUML packets which make STM uCs set the transceiver attenuation. Some people did work to get details about these packets, but this was never investigated to the end.
Source:
Power zone (FCC/CE) in GL300a/b/c RC Firmware · Issue #10 · o-gs/dji-firmware-tools

So conclusions:
a) it is possible to just replace all attenuation levels set by the firmwares to a constant value equal to minimum attenuation. Not really hard for the Github guys. Though I'm not sure I would be comfortable in flying a drone with such brute-force changes.
b) it is possible to investigate the DUML packets further - capture them from a running drone, and then analyse to get an understanding about which chip makes a decision about power zone.

This is as far as I got. Contact the Github guys for an update.

For more background info, check out my description of the video pipeline here:
Camera to fried gimbal board bypass.
 
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thank you so much!
Very much appretiated!
Yet I wonder if enybody tryed the P3SE fake gps method and what came out!
When looking for a solution to switch P3SE to fcc mode we found out that the FCC to CE switch was done by the app based on what the aircraft was sending.
Russian Mod 3.1.18 app can't work as it was developed to switch to fcc mode the P3SE which has a different transmission protocol, but if the switch is done by the app there is probably some almost easy way to mod the app not to switch.
Unfortunately I don't think there is any chance to make the fake gps trick work, or at least no way to keep the AC in FCC mode as in P3SE we just found out 3.1.8 version did not switch back to ce mode, but I guess it was only because that version was released when P3SE did not exist.
 
Update:

There is a tool now in development, which extracts parameters from the Lightbiridge firmware and allows modifying it.
And the parameters include transceiver attenuation values, for both AD and Artosyn boards. Actually, it shows that there are more than 2 board types.

Only for advanced users though, it isn't very straightforward to use.

The tool:
lightbridge_stm32_hardcoder.py

Note: I didn't tried it beyond extracting params from one FW, I do not confirm it allows to change power zone.
What I can confirm is that you can extract attenuation values with it. Maybe it is possible to extract from several firmwares and compare how DJI changed the values between FW versions.
 
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Hi all,

i am new to drone flying and will need your expertise in this. My Phantom 3 Professional drone can only fly a maximum distance of 350 m before losing signals and triggering RTH. With interference, I can only from 150 m.

Is it still possible to switch from CE to FCC? I am trying to increase my flying distance.

Greatly appreciate your help.
 
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My Phantom 3 Professional drone can only fly a maximum distance of 350 m before losing signals and triggering RTH. With interference, I can only from 150 m.

This clearly indicates a hardware issue with either the drone or RC. Ph3 pro/adv will have no transmission issues to at least 500m, even in very high interference urban environment. Higher power will not fix a hardware issue. On the contrary, it may burn your drone - if the high power radio signal is created but not transmitted, it reflects back to the amplifier.
 
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