Firmware installation problem on pixhawk 2.4.8

Hi, dear friends,
I have a problem installing plane firmware on my pixhawk 2.4.8.
it is possible to install px4 firmware on board via Qground but I can not install the Ardioupilot firmware on my board with Mission planner. I do appreciate any help or suggestion.
Attached is a picture of the Qground control installation page.
Which platform (fmuv2, fmuv3, . . . ) do I have to select when I am about to install ardupilot?
(After installing firmware from Qground the mission planner can connect to my board. But immediately after downloading find and installing the plane firmware on board the mission planner can not recognize the board)

It depends on what version of 2.4.8 you have. If it’s an older one with 3 IMU’s use Pixhawk1. If it’s a newer one with 1 IMU use Fmuv3.

Thanks for your quick reply Dave,
Unfortunately, it doesn’t work in two cases. For the pixhawk1 I got the error

and for fmuv3 it stacks in the scanning comports step

Use QGC to flash Ardupilot. I suppose PX4 is on there now.
Like this but select Pixhawk1 of course:

I installed the pixhawk1 via Qground. It was successfully installed on board without any effect! Not only the Qgournd but also the mission planner can not now connect to the board. I had the same result with fmuv3!!!
I have attached the screenshot of the result when I tried with the fmuv3.
(The Buzzer is silent after installation and the board can not connect to Qgournd and/or Mission)

Member Claudio gave an almost perfect manual how to install Ardupilot on a Pixhawk 2.4.8. Perhaps useful in your case as well?: Pixhawk 2.4.8 Firmware? - #10 by ClaudioZavagno

Hi Hans,
Unfortunately it didn’t work for me!!!

I don’t know what you are saying. Did it work or not?

I solve the problem. when the mission planner asks me to reconnect the board I must use the reset key on the board, otherwise, it stops in the search for the comport stage.
I installed the “stable 4.0.5 fmuv3” version on board. But I don’t know why I can’t install the newer firmware (the newer firmware than 4.0.5 are installed on board but they don’t work i.e. the buzzer doesn’t make the beeps after installation).

The com port number may be different after the firmware update, so do check for that and ensure you select the correct baud rate, 115200 baud.

If you cant install the latest stable version for Pixhawk1 and find a working com port then I would seriously reconsider using that flight controller for actual flight.

Thanks, @xfacta
I “can” install the stable firmware 4.0.5 fmuv3 for the plane successfully. For the newer versions than 4.0.5, i.e. 4.0.6 to 4.3.6, the mission planner shows 1-connect 2-erase 3-program 4-the frame has been updated (something like that) then there is no beep comes out from Buzzer and the board doesn’t connect to mission planner. I have tested all coms and bauds rate options.
I am curious about what happened from firmware 4.0.5 to 4.0.6 (and later versions) that my board doesn’t work.
again to clearify: I have no problem till version 4.0.5
in version 4.0.6 and later the firmware is installed but doesn’t work. (after installation there is no beep with Buzzer).

Out of curiosity post the screen shot of the Mandatory Hardware>HW ID screen after connecting with whatever version works.

Thank you so much @dkemxr
Please take a look at my HW IDs.

OK, 2 IMU’s so Pixhawk1 is the right firmware.

Dear @dkemxr
I used pixhawk1 but my problem didn’t solve. I “can” install the firmware till 4.0.5. successfully and I “can’t” install the later version.
when I am about to install the new stable version (later than 4.0.5 i.e. 4.0.6 to 4.3.5 for the plane) I do these steps
Mission Planner ->Install Firmware->All Options, and select the below options

then I select Upload Firmware then I have, select coms->erase->program->Upload Done
Then no beep comes to the Buzzer and FC can not connect to the Mission Planner. I have tested all versions from 4.0.6 to 4.3.5 but none works!!!

One more thing to try then I’m out of ideas. Download the .apj file from here:
AP Pixhawk1
Then use Mission Planners “load custom firmware” option to flash it.

didn’t work! give up!

Replace it with a quality branded Flight Controller. Matek and Holybro make some nice FC’s that are reasonably priced.

Thank you @dkemxr for your assistance. I am about to set up a VTOL plane. Does the version 4.0.5 firmware have this capability?

Yes, but I would use another Flight Controller V4.0.5 is 3yrs old… Matek makes a Flight Controller configured for VTOL’s for ~$70. F405-VTOL