JHEMCU GSF405A - a 3.3g 1-2S F405 AIO FC w/5A ESCs, BMP280, BB, and 2.4G ELRS!

Koh_Sueda · August 3, 2022, 9:26am

Hi,

I tried ELRS firmware update via Betaflight passthrough but it is not successful. Do you have any advice for me? My ELRS configurator settings are:

Device category: JHEMCU 2.4 GHz
Target: JHEMCU RX24T 2400 RX, JHEMCU EP24S 2400 RX, JHEMCU SP24S 2400 RX
*I tried all 3 “Target” above. then I saw the error as follows:

======== PASSTHROUGH INIT ========
  Trying to initialize COM13 @ 420000


 [ERROR] Invalid serial RX configuration detected:
    !!! serialrx_provider != CRSF !!!
Traceback (most recent call last):
  File "C:\Users\apoch\AppData\Roaming\ExpressLRS Configurator\firmwares\github\ExpressLRS\src/python/BFinitPassthrough.py", line 170, in <module>

    Please change the configuration and try again!

    bf_passthrough_init(args.port, args.baud)
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\apoch\AppData\Roaming\ExpressLRS Configurator\firmwares\github\ExpressLRS\src/python/BFinitPassthrough.py", line 77, in bf_passthrough_init
    raise PassthroughFailed(error)
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
PassthroughFailed: 

 [ERROR] Invalid serial RX configuration detected:
    !!! serialrx_provider != CRSF !!!

    Please change the configuration and try again!

*** [upload] Error 1
========================= [FAILED] Took 44.91 seconds =========================

Environment                                           Status    Duration
----------------------------------------------------  --------  ------------
DIY_2400_RX_ESP8285_SX1280_via_BetaflightPassthrough  FAILED    00:00:44.912
==================== 1 failed, 0 succeeded in 00:00:44.912 ====================

cyrilhl · August 3, 2022, 3:55pm

According to information on JHEMCU GitHub, in ELRS.7z file shows the target should be “DIY 2400 RX” and device is “DIY 2400 RX ESP8285 SX1280”.

And your result is normal fail case in my previous try and error. Even I success one time, I cannot understand how that time is working. I can only tell you that the time I successfully is plug the FC and wait for 2 to 3 sec, then I click “Build and Flash” in betaflight passthrough mode

mamario · August 15, 2022, 3:29pm

Are you following these steps for flashing with betaflight passthrough Betaflight Passthrough - ExpressLRS ? it seems that the RX will need to be powered off which suggests that a built-in elrs cannot be flashed using this method. So it might be the cause for some of your successful tries?

cyrilhl · August 15, 2022, 4:39pm

I found a post about this issue in intoFPV

V-22 has mentioned
“2. To flash ELRS via Passthrough, you may need to put the receiver into bootloader mode. For some reason, this requires holding down both buttons on the FC when you plug in USB. A pair of alligator clips comes in handy. After you do that, the correct target to flash is DIY_2400_RX_ESP8285_SX1280_via_BetaflightPassthrough.”

I think i maybe go into this mode unintentionally

You can read through the thread to have the whole picture of the story

https://intofpv.com/t-mobigital-7-build?page=2

mamario · August 17, 2022, 3:56am

holding 2 buttons when plugging in USB is not right since FC will be in DFU mode thus no COM port will be available for elrs flashing

CrashTestPilot · August 17, 2022, 6:03am

It is showing you the error, you don’t have SerialRX set to CRSF. Also you want to use the DIY 2400 RX ESP8285 SX1280 target as cyrilhl mentioned below.

Refer to the ExpressLRS website for full instructions on wiring, FC configuration, and flashing: Configuring FC - ExpressLRS

CrashTestPilot · August 17, 2022, 6:05am

It looks like you are trying to build a very old version of the target. Due to platformio updates, most of the old targets won’t build anymore. You should be selecting 2.5.1 or 3.0.0-RC2. Also, you almost certainly do not want NO SYNC ON ARM enabled.

You would think so, but for some reason the ESP32 seems to win. I have several of these boards now, and their behavior is all slightly different (to be expected with JHEMCU). One board could only be flashed via WiFi when it was sitting on top of my WiFi AP, on another board the WiFi is completely dead. One board I was able to put into bootloader mode just by holding down the ELRS RX button, on another board I needed to hold down both buttons to put the receiver into bootloader mode to be able to successfully flash via WiFi. And some boards do not have loading caps near the crystal and seem to be within spec, while other boards have loading caps that must be removed for the receiver to connect at all (see: Crystal Oscillator (XO) Frequency Error · ExpressLRS/ExpressLRS Wiki · GitHub).

Also, @marco3dr recently discovered a way to flash ELRS via passthrough on Ardupilot:

I do not remember where I had read it in the wiki but to flash a rx R9 Mini with Ardupilot in passthrough it was necessary to set the SERIAL_PROTOCOL to -1 of the UART related to the rx.
After trying a billion times without ever being able to flash the rx in that way I found out how it always works.
Leave the serial protocol at 23 (CRFS) and the receiver must be binded and connected to the tx module.
Then carry out the passthrough using the appropriate parameter in Ardupilot and the rx will flash without any problem.
If the rx is not connected to the tx module the procedure will not work, it cannot find the rx bootloader, don’t ask me why.
but so it always works here.
Tested with Matek H743-Slim and Pixhaek 2.4.8.

Link to join the ELRS Discord if you do not have access to the above:

This was also mentioned early on in the thread here: JHEMCU GSF405A - a 3.3g 1-2S F405 AIO FC w/5A ESCs, BMP280, BB, and 2.4G ELRS! - #17 by CrashTestPilot

marco3dr · August 17, 2022, 7:31am

To flash the rx via Ardupilot passthrough follow this steps:

set the SERIAL_PASSTIMO parameter to 0 so you don’t have any timeout and reboot the board
set the SERIAL_PASS2 on the serial where the rx is connected
don’t change the serial protocol on that port, leave it at 23
imperative: keep the receiver connected to the module, it must be gone and connected or the procedure will not work, so if it is the first time that the rx receives the firmware it will not work, in that case it uses a USB-TTL board.

Pay attention to this problem, which is present and verified by me several times.
The R9 Mini with the ELRS V3-RC2 occasionally crashes, randomly.
With other receivers based on ESP8285 I don’t have this problem so pay attention to the rx based on STM32 MCU.
It is not yet understood if it is a problem in the code but surely with the FrSky firmware it is stable, so something that haunts the receiver is in the ELRS firmware.

mamario · August 18, 2022, 2:02am

I finally figured it out. To flash firmware on this board using ELRS configurator via uart is to connect the USB-TTL TX to the TX1, USB-TTL RX to RX1 to the board (this is because the silkscreen for TX1 and RX1 shows the FC side UART which is the opposite to the receiver side, since we want to talk to the receiver, we need to wire it accordingly.) Of course, we will need the USB-TTL ground to the FC ground and USB-TTL 5V to the FC 5v.

Hold down ONLY the receiver boot button and plug in the USB-TTL and you can select the correct port in the ELRS configurator and start the firmware flashing.

According to JHEMCU, the board with the BMI imu should support WiFi firmware flashing. The one I am working with is the MPU imu version so unfortunately it will not support that.

mamario · August 18, 2022, 2:04am

you can try my suggested method by flashing through UART

Koh_Sueda · August 19, 2022, 12:15am

Hi, thank you for your information!
I’ll get a USB-TTL and try it again

mamario · September 8, 2022, 3:18am

Also, must make sure that when holding down the receiver boot button and plug in the USB. the receiver LED needs to be solid green which indicates that it is in boot mode. If it is still slowling blinking and then fast blinking, this means it did not enter boot mode successfully. It is likely that you did not press down the button correctly or the boot button is spoiled. If it is the latter case, you can use a tweezer to bridge both sides (4 pads).

manbehindthemadness · September 22, 2022, 7:44pm

So I also was just wrestling with this, my solution turned out a little weird:

Set serial to -1
Reboot normally
Connect ftdi to onboard pads
Open betaflight and select the serial ftdi and not connect.
Use the ELRS configurator to flash using “betaflight pass through”
Profit.

CrashTestPilot · February 14, 2023, 9:05pm

It looks like one of the new versions comes with the BMI270 gyro, so the hwdef will need to be updated. I have one of the new BMI boards on order to test.

yamigos · February 15, 2023, 5:36am

Yes, there new bmi in description

andyp1per · February 15, 2023, 7:22am

You will need to add two lines like this:

SPIDEV bmi270    SPI1 DEVID2 MPU6000_CS   MODE3   1*MHZ  10*MHZ
IMU BMI270 SPI:bmi270 ROTATION_PITCH_180

You will need to adjust for SPI bus and rotation

geofrancis · February 20, 2023, 2:15pm

can a servo be attached to this anywhere?

MaxBuzz · February 21, 2023, 5:48am

It supports one servo channel, which, as far as I understand, is indicated as LED in the documentation.

ltwin8 · March 1, 2023, 12:07am

Hi there, I have a lil build that I would like to try Ardupilot on, not experienced with Ardupilot at all.

I have a rekon 3 frame (1S 18650VTC6) currently running inav, the board is the GAF405A-BMI

The other hardware includes a Walksnail 1S VTX, a matek m8q GPS and mag…

I would love to fly it on Ardupilot since I like the idea of a autonomous little 18650 powered quad which has long flighttime and thanks to ELRS also great range

Carvalhais_Aviation · May 18, 2023, 9:20pm

Hy, can some one add the Target for the gsf405a-bmi? I would love to use this board