Source
r/olkb•
niv-gs

Could case-magnets have ruined my PCB?

Hi,

I've been using an Iris rev. 4 for almost a year now. Recently I tried gluing on magnets to the acrylic cases backs for more convenient travel and ever since, my left side PCB doesn't respond.

When I plug the keyboard to the PC via the left PCB, it is registered in the Windows device manager, but it both sides don't respond (nothing happens when I type).

When I plug it via the right PCB, typing on the right side does work, but typing on the left doesn't.

The left PCB doesn't look to have been damaged:

https://preview.redd.it/t1ko43wdagh91.jpg?width=4624&format=pjpg&auto=webp&s=5012be01c486e0026a75f96b5a5f3d69dc5b8e0b

https://preview.redd.it/wke896wdagh91.jpg?width=4624&format=pjpg&auto=webp&s=2ff0eade4483753445ee2475c5c38341b7384ac6

I tried hovering a magnet over the PCB and it seems it doesn't have any magnetic parts.

Does anyone have an idea how I can debug this, extract more info on the actual failure? or general fix ideas? I'm getting hopeless.

Thanks!

Posted Aug 13, 2022, 9:37 AM UTC

613
qw3r3wq•

Magnets should not have done anything.

How do you connect the time when it stopped working? Over left or right side to PC?

Have you tried connecting left side over usb to linux box and check dmesg?

Are you sure that trs cable or socket are good? Maybe they fried it?

2
niv-gsOP•

I was connected over the right side to the PC.

I tried with different cables and had the same results. And I don't think the TRRS cable having fried the board is the issue, I've been careful about that.

About dmesg, I'm attaching a link to the diff between the outputs when attaching either side. I'm not very familiar with this tool but nothing seems off to me... do you see anything I might've missed?

1
qw3r3wq•

Exactly as you said, all looks good. Have you tried to rewrite fw?

It do not respond as dead... It respond well. Have you tried checking with multimeter?

1
niv-gsOP•

I didn't try to rewrite the firmware as it seemed irrelevant to the magnets issue, but I'll give it a shot.

I'll try to get my hands on a multimeter. Once I do, what should I check?

1
qw3r3wq•

Sorry to reply late, I saw you already solved.

With multimeter, I would test trrs connectors, to check connection between them. Also check if signal comes to the board. That helped me.

2
FossilOG•

SpongeBob one goes for same amount

1
FlynnsAvatar•

No. If you had a magnet strong enough to actually affect flash you could lift a freight train or tear the iron out of your blood with it.

Vast majority of the metals are also not ferrous. Aluminum, copper, cadmium, zinc , etc.

IMHO, All the symptoms you’ve described put the TRRS connection(s) as the most probable issue. Cable, connectors , etc. try replacing cable, resoldering TRRS connectors ( possible cold joints )…

2
COrthbandt•

I added strong magnets to multiple Irises (Rev 4 and 5) and this never caused any issues.

But: I either embedded them in the bottom case so that the magnets cannot possibly touch the PCB. Or in other cases I glued them to the PCB too so they won't move around.

I'm using the magnets to "snap" on custom tenting legs.

2
niv-gsOP•

For anyone interested, eventually I solved it by both changing the TRRS cable, and re-flashing the PCBs.

2
OddStation6579•

ever thought is the TRRS cable or socket giving you problem? If you are handy with a multi-tester, you can try to test it out to make sure it is making proper connection on both side via the cable....

1
OddStation6579•

Oh ya... If you have ever pulled the cable joining the 2 halves when it is still connected to the usb, you run the risk of frying your controller too...

1
niv-gsOP•

I don't think the TRRS cable having fried the board is the issue, I've been careful about that.

I'll try to get my hands on a multi-tester. What should I check when I do?

1
OddStation6579•

With the cable plugged in, do a continuity test from the solder join on 1 board to the other. Wiggle the cable around when u testing it.. just to rule out the possibility of a broken wire in the cable.

1