Game Input MultipleXer

Hello, problem already seen here but with no public solution so I have to ask.

I used a CP2102 and a atmega32u4, connected as shown here:
https://gimx.fr/wiki/index.php?title=DIY_USB_adapter

Then I loaded the firmware using gimx 8.0 with emug29ps4, made my config to use my sim hardware as a g29. Everything seemed good so far.

I plugged it in my started ps4, disconnected the DS4 and started gimx launcher with my config and got this: As mentionned in the wiki, I tried inverting rx/tx, but it changed nothing. I have only one port detected (and none if I disconnect it) so no possible error here too. Last suggested thing to do is to verify the firmware. If I click on verify in gimx launcher it just tells me "joystick not found".

edit: my config is a Xeon v3 on windows 10, 32gb of ram and I don't know if there's anything else useful

Hopefully the solution is simple.

No one ?

Hello.
Have you soldered the wires between the cp2102 and atmega?
Also when you installed Gimx did you reboot the computer?
These might sound like stupid questions but they are infact important.

Bad connection when using jumperwires.
And the amount of fault people are having with gimx if not rebooting before using for the first time after installing the drivers are alot.

If these steps does not help, try connecting the atmega to the pc to see that it is recoqnized by windows properly.
If not there is as chance that its broken.

You can post picture of your adapter incase the wiring is incorrect on the adapter (Adapter might have wrong wiring placement.)

You have the DS4 connected to your PC right?
Hope this helps.

Thanks for the answer.

I did reboot my computer after installing gimx.

I do use jumpwire so I might check it.

How are the atmega supposed to be recognized as ? After flashing the firmware none were visible on windows, though I noticed one has a green led light and the other two a red one.

And yes the DS4 was connected to my pc.

https://i.ibb.co/JwGfMFJ0/IMG-20250227-154739.jpg
https://i.ibb.co/JwGfMFJ0/IMG-20250227-154739.jpg

Device manager should have the atmega showing.
Like this

Yes i highly recomment that you solder the wires since the connection is unstable with jumper connections.
If you think its hard to solder those three wires on the atmega board, you can make it easier just by using the ground point on the other side of the board.

Since the boards leds are lightning up, there is no power issue atleast.

On the logg it says you are using windows 10. If you are using windows 11 it might be the issue.
Drivers are not updated for that OS.

Sorry for the late answer, I didn't have much time those last two weeks.

I'm on Windows 10. And I confirm that none of the board are recognized after flashing them.

I'll try to do the soldering this week-end.

shenron67 wrote: ↑Wed Mar 12, 2025 4:38 pm Sorry for the late answer, I didn't have much time those last two weeks.

I'm on Windows 10. And I confirm that none of the board are recognized after flashing them.

I'll try to do the soldering this week-end.

Hopefully after soldering is done the issue is gone.

Had a conversation with another dude about some issues.
He used an older version of Gimx.
https://forum.gimx.fr/viewtopic.php?t=3144

If none of these work, i'm out of options

Good news everyone, it works.

I ended up not soldering it, why ? Because I wasn't able to remove the pin header. So I reconnected every pin, electrically tested everything, it was good. Tried again, and didn't work.

I resetted the board, reflashed it (important thing that I saw only in one thread about resetting the board: you need to reset it again and when it start writing the firmware so it doesn't disconnect).
I plugged it on PS4, clicked on "verify" and it still told me that there was no G27/G29.
I clicked on start and, as usual, same error.

As you know, a common mistake was the tx/rx connection, I already tried reversing the two in case there was false advertisement about my board being "with the right label". I thought that I might as well try again and here I realise that I never re-reversed it. When I reconnected the pin as mentionned before, I just kept the cable in the same order. We can see it on the picture I've posted too: the RX goes on the RXI.
I tried and it worked.

In conclusion: there probably was a connection problem, or a firmware problem as I already switched the connection, I reflashed it, and way too late realise that I didn't put the pin in the right order again.

Well done bro

Thank you, without your answers I'd have gave up.