Passthrough telemetry over CRSF (crossfire)

yaapu · November 23, 2020, 10:43pm

ok, version 4.06 added support for an ardupilot reserved frame id, I have no idea if tracer firmware was updated as well, need to check with TBS, you’ll know if rf mode detection works by looking for messages like CRSF: rf_mode etc

JoshW · November 23, 2020, 10:43pm

I suppose we can pose the question to Remo but let me test first.

yaapu · November 23, 2020, 10:44pm

Yeah, I just asked Remo for more info

JoshW · November 24, 2020, 12:12am

It doesn’t appear to work, but qq: the TELEMx_FUNCTION in your write-up says 23, which is RCIN… why wouldn’t it be 29 (Crossfire)? Is that not fully supported yet?

edit: It must not be, because if I change to 29, I get no working RC. Odd…

akhilzid · November 24, 2020, 3:54am

Reporting successful copter build and test
with CUAV pixhack V3x using branch test/crsf_telem_passthrough

TX : Qx7 + opentx 2.3.10 + Crossfire Micro tx v2
Rc : crossfire Nano rx

yaapu · November 24, 2020, 8:38am

@vierfuffzig, @andyp1per and I played with DMA on the omnibusf4pro (really need to thank Andy for helping me out on this) and we can state that DMA is a requirement for CRSF to work at full speed.
The MatekF405-Wing suffers the same lack of available DMA streams, if you check

build/MatekF405-Wing/hwdef.h

after running

./waf configure --board MatekF405-Wing

you’ll see that the DMA resolver cannot find a dma stream for any UART except for UART1 (UART2 has the NODMA directive)

// Note: The following peripherals can't be resolved for DMA: ['UART4_RX', 'USART6_RX', 'USART3_RX', 'UART5_RX']

vierfuffzig · November 24, 2020, 5:59pm

thanks @andyp1per and @yaapu for persistently tracking this down. if i understand this right it might not be easily resolvable though and limit full speed crsf support to a single uart on quite a few boards though…?

yaapu · November 24, 2020, 7:24pm

@vierfuffzig well yes, at least for F4 an F7 boards, CubeOrange (H743) on SERIAL4 (GPS2) has TX DMA disabled but I get 160Hz no problem whereas on a kakute F7 dma is required on both TX/RX to get 160Hz

shoyboom · November 27, 2020, 5:35pm

hello.
could you build a version for [F35Lightning] board.

yaapu · November 28, 2020, 10:38pm

Hi, please check version 0.9 here it has an F35lightning build

Alex.

yaapu · November 28, 2020, 10:50pm

Hi all,
I updated the test builds, version 0.9 is available here

This version has better rf mode detection and it’s compatible with the crossfire lua parameters script.
On non DMA uarts telemetry works fine but the crossfire lua script is kind of slow in getting the parameters from ardupilot, not much we can do about this.

I tested it with crossfire fw 3.72 up to 4.08 on a Micro TX V2.
It requires a newer yaapu script, version 1.9.1 beta1, download from here

cheers,

Alex

JoshW · November 28, 2020, 11:49pm

Hi Alex,

Thanks again so much for your efforts here. These enhancements really do make ArduPilot more fun to fly!

I saw that you now have a “pr” version of the pr in addition to the test one. Is that the one we should be building off of if we’re building ourselves, or would you prefer we stick with the “test” one?

Thanks again so much for everything!

Josh

PS Any word back from Remo on Tracer supporting this enhancement?

shoyboom · November 29, 2020, 6:17am

Thank you, Alex.
I’ll try it.

yaapu · November 29, 2020, 1:15pm

Hi Josh,
right now the pr version is identical to the test one, I have distinct branches so I can change the pr one without affecting testing. You can compile either one.
No feedback from Remo about the tracer. Did you ever have success with it?
You should use serial protocol 23 and hopefully get RC + telemetry, use a UART with dma enabled.

Edit: The TRacer manual says it has a single rf mode (up to 15 miles in “rural” environment), and fw versioning is distinct from the TBS legacy one. I’ll need for sure a way to detect tracer vs tbs and change the way I handle rf mode switching

JoshW · November 30, 2020, 12:22am

No success.

Can you confirm which UART I should be using for normal CRSF on CubeOrange?

master-of-desaster-8 · November 30, 2020, 7:29am

Hi Alex,
I have tested Your last version compiled from Your test branch ( ff56022 ).
I tested it with crossfire fw 3.72 on a Micro TX V2 - yaapu script, version 1.9.1 beta1.
Settings same as at the last test.
Working fine at distances over 1000m.
Just missing the “Air Speed”
Cheers, Markus

yaapu · November 30, 2020, 8:18am

Thanks Markus, your feedback is really welcome!

Missing “Air Speed” because you do not have the separate indicator for both groundspeed and airspeed (like when using the MavToPT firmware) correct?

yaapu · November 30, 2020, 8:29am

Hi Josh,
Telem1 and Telem2 are fine, don’t use GPS 1 (DMA on RX is disabled), GPS 2 has DMA only on RX but in my testing CRSF works fine @160Hz, so to recap:

telem 1
telem 2
gps 2

Alex

master-of-desaster-8 · November 30, 2020, 9:08am

Thats correct. The "Airspeed" was only implemented at the "Plus Version" from Erics MavlinkToPassthru.

0x50F2 VFR_Heads Up Display

Cheers, Markus

yaapu · November 30, 2020, 9:14am

OK, I’ll be able to get that from scripting as soon as the frsky scripting PR gets in.
Telemetry data injected from scripting will work for both passthrough over frsky and over crossfire.