Contents
- 1Updates
- 2Known Working Receivers
- 3Goal
- 4Back Up Your Betaflight Configuration
- 5Original HappyModel Firmware
- 6Install And Configuration
- 6.1Back Up Your Stuff
- 7Download And Flash Custom Firmware
- 7.1Verify Firmware Installed
- 7.2Restore Your Configuration
- 7.3Enable Soft Serial
- 7.4Configure Soft Serial
- 7.5Where Is The PWM5 and LED Pad?
- 7.6Thats pretty much it.
- 7.7Notes
- 8FrSky Mobula7 Only, Not Really
- 9Changing VTX Channels/Bands
- 10F.Port
- 11None F.Port || Crossfire Receivers
- 12 Maiden Flight
Updates
v7 added fujins workaround for smart audio 2.1
v6 HoTT Telemetry, XBUS, SUMD, SUMH, PWM, MSP.
v5 that should support almost all receivers. The default hard wired SPI receivers have been removed from the firmware to make room for Crossfire, Spektrum, IBUS, SBUS, F.Port.
This should support all versions of the Mobula7. FrSky, DSMX and FlySky are technically the same board with different configurations per built in receiver. Removing those and adding the others fit inside the space allowed on the F3.
Known Working Receivers
Crossfire and F.Port and XM+
Goal
The goal of this project is two be able to run a full receiver and use smart audio? As of this post the CRAZYBEEF3FR does not allow Soft Serial, and it looks like crossfire is disabled. Using the internet I found out how to configure the features of the firmware. If you proceed make sure you read the Notes section at the bottom. Read the Notes section.
Back Up Your Betaflight Configuration
Before you begin any of this process back up and know your current firmware version. If you don’t know how to back up your betaflight configuration you should not be here, yet. Click here to find out about backing up your BetaFlight.
Original HappyModel Firmware
If you need to flash back to original HappyModel mobula7 firmware you can get it from happymodel here. Or below
Install And Configuration
Back Up Your Stuff
You will need to make sure you backed up your configuration. You will need to get your quad into DFU / bootloader mode. To find out how to get your quad in DFU / bootloader mode click here.
Download And Flash Custom Firmware
Flash the below firmware using the Load Firmware [Local] button. If you dont know how to flash firmware click here, and come back later.
This version has softserial and crossfire enabled. As of version 5 DSMX and IBUS should work.
Firmware Release Notes and other versions
Verify Firmware Installed
Once you have flashed the firmware you can verify the custom version by the release date in the betaflight log when you connect to betaflight.
V5 — Running firmware released on: Jan 6 2019 21:13:13
Click Show Log if you do not see the version
Restore Your Configuration
After flashing, restore your BetaFlight configuration and CLI backup.
Enable Soft Serial
The main reason for this firmware is to make available soft serial.
Click on the Configuration tab and enable soft serial. Save and reboot.
With soft serial enabled click the CLI tab. Copy and paste this into the command input and hit enter.
resource motor 5 none
resource led_strip 1 none
resource SERIAL_TX 11 B06
resource SERIAL_RX 11 B04
save
this will create a soft serial port and reboot the flight controller
Configure Soft Serial
What we have done is told the flight controller to pretend that the PWM5 pad is TX pad and the LED strip is a RX pad on the same UART. My testing and configuration used the UART3 for F.Port and TBS Crossfire. My configuration is having the smart audio configured on the softserial. I say this to explain the below image.
Click Ports and you will now see a SOFTSERIAL1 (1). Set the SOFTSERIAL1 peripherals to match your VTX protocol (2). The mobula7 stock is TBS Smart audio. I have crossfired configured on UART3 with Serial Rx enabled.
Where Is The PWM5 and LED Pad?
In my working configuration I moved the smart audio cable to SOFTSERIAL1 TX that is known as the PWM5 pad.
Thats pretty much it.
You should be able to bind your transmitter and use smart audio. If you have not read the notes. Read them.
Notes
FrSky Mobula7 Only, Not Really
This has only been tested on the FrSky version of the mobula7 CrazyBee F3 AIO. However stating that, in theory it should work for all versions, if you know how to configure your receiver on an F3 uart. F3’s handle inversion a lot better than F4’s.
Updated: DSXM and IBUS I cant test. Any feedback of V5 for these would be useful.
Changing VTX Channels/Bands
One important difference when changing VTX settings with smart audio in this configuration is that in order to get the new band/channel to change after you have set it in the OSD, you need to back all the way out of the OSD menu to the main menu, save and reboot.
F.Port
F.Port – I had to do this in CLI to get F.Port working properly.
set serialrx_halfduplex = ONset serialrx_inverted = ON
save
run this from CLI tab
None F.Port || Crossfire Receivers
The only two receivers I have tested this with are the Crossfire nano and the F.Port on the R9MM. Both of them worked.
One thing to keep in mind is inverted singals. If you have issues, you may be able to work around it with this in the CLI
set serialrx_inverted = ON
save
run this from CLI tab
Had problems with my docker, so couldn’r get a homebrew done myself and stumbled upon yours. What options did you leave out to make it fit?
I would like to use softserial and ledstrip. is ledstrip support in your build included?
Maybe put in the notes what features are in and which are out?
You might be able to run smart audio with one wire on the tx and change the LED_STRIP pad back to a strip pad.
resource SERIAL_RX 11 none
resource led_strip 1 B04
then save. if you have smart audio on the pwm5 pad and have issues it may be because half the uart is missing. if it works, it would be good to know.
also i dont think dsmx or ibus work with the current version. working on that now but need someone to test.
Looking at some of the discussions about LED features, LED_STRIP seems to be taken out of the master branch of all F3 firmware releases. Even if you wired it, I am not sure it would work. In theory it shouldn’t.
https://github.com/betaflight/betaflight/pull/7303
I have an R-XSR receiver, flashed for FPort. Will it be possible to to use both RX/TX and Smartaudio on one wire? My plan was to have lua scrips/Smartaudio and also Telemetry working…?
No but I have tested this with fport and smart audio and they both work. I wired Fport to UART3 RX and smart audio cable to the PWM5 pad shown above.
Thanks, I will give it a try asap!
I’m trying to set this up with a XM+ but I can’t get it to work. Maybe I understand the picture wrong but do I need to connect the SBUS cable to the LED strip or to the RX3? In the CLI it gives an “**INVALID** response to “resource led_strip 1 none”
Did you enable soft serial?
What do you get when you type
resource SERIAL_TX 11 B06
resource SERIAL_RX 11 B04
In cli?
If you didn’t restore a config that had led_strip you might see that error.
I use uart3 pads for receiver and pwm5 pad for smartaudio.
Yeah I enabled soft serial but I soldered the SBUS wire to the LED pad, marked with the green arrow and RX. But I think that’s where it went wrong. The SBUS is now connected to the RX3 (next to the pad where the SmartAudio used to be) and with stock firmware I get response on stick inputs in Betaflight. I’ll try your custom firmware tonight, see if it works. Will keep you updated
I have the same problem, did everything as in the instructions above, and it comes with the command “resource led_strip 1 none” again and again “** INVALID **”. The Smart Audio cable on the Pwm5 pad does not work either.
I use a FrSky XM +. Flying is very good with the BF version, only Smart Audio does not work, unfortunately.
Its ok if the LED resource gives an error. As long as B04 is assigned to the RX serial port for the soft serial. This command does that: resource SERIAL_RX 11 B04 And as long as B04 isnt assigned as another resource, it should be fine. You can see this by typing resource in betaflight CLI. I would recommend using the UART 3 for your receiver and the PWM5 pad as your smart audio TX cable. The stock firmware will not allow for soft serial. So going back to the stock firmware shouldn’t affect your UART3. It will however prevent… Read more »
I have the same issue. I wired my XM+ to the RX3 and Smartaudio cable to the PWM5 pad and copy and pasted the setup. The XM+ works fine. I am able to enable smart port and I can get to it in my OSD menus. Only thing is I make changes and nothing happens. I also tried to do the commands in CLI and it did not update the VTX. It seems it is not transmitting thru the PWM5 pad. I tried both v5 and v7 firmware with same results. Here are my settings: # resource resource BEEPER 1… Read more »
I have tried the setup with an XM+ and the Happymodel Whoop VTX. I followed the instructions to flash the firmware (and confirmed) and I also wired as suggested. The XM+ is on the RX3 and the VTX SmartAudio is on the PWM5. The XM+ works perfectly. As for the VTX, I now have the smart audio option in my OSD but when I make changes it appears that the changes don’t get transmitted to the VTX and nothing happens. I have checked resources and they are assigned correctly. I done some testing and if I assign them incorrectly then… Read more »
Hi Steve, same situation here. Were you able to get it working?
Thank you for this, I made the mistake of ordering a flysky rather than FrSky version of the M7 and decided it was faster to just hook-up an r-xsr rather than sending it back.
I was very displeased to find out that softserial was disabled in the BF target.
I can confirm that this works with the F3FS target. You do have to re-boot to write a VTX change though.
I also suggest using the beta65 pids as they are way better than stock.
First off, great write-up…very detailed. Nothing I’ve done has been able to get the R-XSR to work with the LED or Motor5 pads, either under SBUS or FPORT (which won’t save in the ports tab). Additionally, was not able to get FPORT to work with the UART3 RX pad. However, I was able to get SBUS working on the UART3 RX pad with SA on the PWM5 pad. To note, each person should run the RESOURCE LIST before they assign/free any. My LED was on B03, not B04. Brilliant solution – I’ve remapped tons of UARTS, but never thought to… Read more »
I flashed the V7 version on my FlySky F3 board after making the switch to FrSky transmitter (Q X7S). I first tested an IBUS receiver on RX3 and confirm this works also. Might be usefull to know somebody if their internal FlySky receiver brakes down. Then I connected an FrSky XM (not the +) receiver to RX3. Took me some time to get it working because I had my TX on D16 CH 1-8. In the end I found that I needed to use D16 CH1-16 for the XM to work. I stuck the XM on the board using double… Read more »
Is there any other links available for V5 or V7 to aownload?
When I click your links it takes me to another of your pages and there nothing to download.
Help grately appreciated
They seem to still be working. It could be a security issue with your browser, It may not like the .hex extension being downloaded.
Can you direct me to where I can download v5 or v7 please. Your links are not working. I can only download v3 from your links. Thanks
They seem to still be working. It could be a security issue with your browser, It may not like the .hex extension being downloaded.
Hi, Any chance you can make a new build based on BetaFlight 4.0.2?
Using this on 2 Flysky boards. I upgraded the receivers to Flit14+ Flysky receivers. Both wired to RX3. One is running a Runcam TX200U VTX which is Tramp Protocol. The other is an AKK 16×16 VTX that is Smart Audio. Both wired to PWM5 and everything works great! Thank you so much!
You are welcome. Glad it worked out!
Hello,
I am trying to replicate what you have done in my own betaflight git project, but am having issues. Do you have your source code somewhere so i can see the changes you made?
Thank you for your help.
Does this work on my Mobula 7 with CRAZYBEE F4 PRO V2.0? It has the Frsky RX.
Hi I cantfly,
I got Mobula7 from my friend. I’m a user of Tango 2 transmitter, so I need crsf. I was finally able to have inputs on stick movement with your firmware. Unfortunately, I’m not able to get into Modes tab in Betaflight. It is shown in Note 2 here https://www.dronejunkie.co.uk/racerstar-crazybee-f3-flight-controller-ur65-4-in-1-5a-1s-blheli_s-esc-compatible-frsky-d8-receiver
Do you have pls any hint how can I configure arming, beeper….
I was really keen to try Mobula for first time and this happened.
Thanks
Dusan
I realise this is old but I am in lockdown and have a mobula7 but it’s FlySky and I don’t have tx anymore I also have an xm+. Tried flashing and all worked apart from BF configurator wont let me set any modes up. Any ideas?
Thanks
will it work with mobula 7v2 and crossfire nano rx?
More than likely you dont need this to get crossfire and a micro rx to work. Can you take a picture of the board thats in there? From what I read this is the F4 board. Which eventually is what I upgraded all of my mobulas to. However when I bough the f4 boards, I made sure they didnt come with any SPI receivers built in. I first tried https://pyrodrone.com/products/happymodel-crazybee-f4-pro-v3-aio-whoop-flight-controller-for-larva-sailfly-mobula. What I ended up putting on my quads was https://amzn.to/2GM39Th. The betaflight f4 has more room. However the big problem with it and most whoop boards is the pre soldered… Read more »
Thanks for your reply I have the SPI version, so just for now.. I upgraded my Taranis xq7 radio with a software that allowed me pair the EU LBT radio with SPI frsky non-eu receiver in D8 mode Must say- it seems to be working just fine, so the receiver is not the bottleneck- rather VTX signal range is, but surprisingly it also does pretty well as for that tiny drone Also- not sure what antenna you are using for the crossfire, but I only have the immortal T for 5″ and that wire antennas for 5″, and for the… Read more »