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Lost an entire column

Lost an entire column

From:
Sean Escriva
Date:
2015-04-08 @ 03:33
Guessing it's just a construction flaw on my part, but today the entire 
far right column went out. I've been using it as my daily since I built it
a while back. 

Enter / ; P all failed. 

Tomorrow I'll be pulling it apart to check the solder, just a heads up to 
other builders I guess. Make sure those solder joints are solid!

-sme

Re: [atreus] Lost an entire column

From:
Jd Carpenter
Date:
2015-04-08 @ 03:39
If it's an entire column, it's either the first diode in that column, or
more likely, the header pin on the controller that connects it to the
column on the PCB.

On Tuesday, April 7, 2015, Sean Escriva <sean@escrivas.com> wrote:

> Guessing it's just a construction flaw on my part, but today the entire
> far right column went out. I've been using it as my daily since I built it
> a while back.
>
> Enter / ; P all failed.
>
> Tomorrow I'll be pulling it apart to check the solder, just a heads up to
> other builders I guess. Make sure those solder joints are solid!
>
> -sme
>

Re: [atreus] Lost an entire column

From:
Phil Hagelberg
Date:
2015-04-08 @ 06:56
JD Carpenter <jdcarpe@gmail.com> writes:

> If it's an entire column, it's either the first diode in that column, or
> more likely, the header pin on the controller that connects it to the
> column on the PCB.

The diodes are actually laid out in parallel, so a single diode failing
would only cause a single switch to go out, not a column.

You can see here that the far right column is connected by a trace on
the back across over to the middle...

  http://gerblook.org/pcb/NxuQ7JEGZ9KDHQV3TiAaLe#back

Then (remember the front side is flipped, so look at the left for this
one) through a via to the front side and to the 4th pin down on the
controller's left side:

  http://gerblook.org/pcb/NxuQ7JEGZ9KDHQV3TiAaLe#front

If you're lucky, the bad joint is on the exposed side of the PCB. This
is easy to fix; just take your iron to that pin and re-flow.

There's a chance that the bad joint is on the microcontroller
itself. This is a much bigger hassle to repair as it involves
desoldering the switches so you can get at the controller.

Give it a try re-flowing the pin on the exposed side; hopefully that
does the trick. You can also try connecting that 4th pin to any of the
bottom 4 pins on that side of the microcontroller with a wire. If that
works, then the problem shouldn't require removing the switches to
fix. If not, let me know and I can walk you through the steps of fixing
it on the other side.

-Phil

Re: [atreus] Lost an entire column

From:
Sean Escriva
Date:
2015-09-05 @ 03:21
On Wed, Apr 8, 2015, at 02:56 AM, Phil Hagelberg wrote:
> JD Carpenter <jdcarpe@gmail.com> writes:

I realized I hadn't responded with any results to this.
 
> > If it's an entire column, it's either the first diode in that column, or
> > more likely, the header pin on the controller that connects it to the
> > column on the PCB.
> 
> The diodes are actually laid out in parallel, so a single diode failing
> would only cause a single switch to go out, not a column.
> 
> You can see here that the far right column is connected by a trace on
> the back across over to the middle...
> 
>   http://gerblook.org/pcb/NxuQ7JEGZ9KDHQV3TiAaLe#back
> 
> Then (remember the front side is flipped, so look at the left for this
> one) through a via to the front side and to the 4th pin down on the
> controller's left side:
> 
>   http://gerblook.org/pcb/NxuQ7JEGZ9KDHQV3TiAaLe#front
 
these graphics help quite a bit for reference

> If you're lucky, the bad joint is on the exposed side of the PCB. This
> is easy to fix; just take your iron to that pin and re-flow.

I've mostly been lazy since I have a kinesis to fall back to using. The
issue 
with the rightmost column is intermittent, but seems to sort of have
resolved 
itself for now.

> There's a chance that the bad joint is on the microcontroller
> itself. This is a much bigger hassle to repair as it involves
> desoldering the switches so you can get at the controller.
> 
> Give it a try re-flowing the pin on the exposed side; hopefully that
> does the trick. You can also try connecting that 4th pin to any of the
> bottom 4 pins on that side of the microcontroller with a wire. If that
> works, then the problem shouldn't require removing the switches to
> fix. If not, let me know and I can walk you through the steps of fixing
> it on the other side.

Since it seems to go in and out I'm hopeful this is all the issue is. 
Is there a good a way to test it, maybe readings on a micro at specific
points?
It seems to be an issue only when I have the case fully assembled, but
if I remove 
the layers of the case and use the keyboard with only the switchplate
the column 
works just fine.

-sean