Help!! Ergodox Thumb Keys Aren't Working!

[clickclack123]

Well, yesterday i got my Ergodox, thanks czarek! It certainly looks the business but…

Unfortunately, the thumb keys on the left hand side aren't working. :-[ When I first plugged it in and loaded the ergodox-kinesis-mod hex, it kept going to the screen you get when you hit ctrl-alt-del over and over.

If I start it with the left hand disconnected, the right hand works fine by itself.

Actually one time I jiggled the cable a bit and both hands worked for a while but at that time none of the left thumb keys did anything.

Then I made my own layout using the massdrop ergodox configurator with just letters on the thumbkeys, this stopped it from going to the ctrl-alt-del screen, but promptly hard-reboots my pc every time!! I think Win7 completely barfs when zillions of keypresses are sent to it. Who knew! Might be a good trick to play on coworkers or people you hate (or even better, coworkers you hate).

Basically I think that there must be a solder bridge somewhere that is making it think that all the thumb keys on the left side are being pressed at once. In the 10 seconds before it crashes the machine, I can see that the left thumb characters were being held when I ran the Aqua key test program.

I don't have a full schematic of the Ergodox, the only one that I could find was a very simplified one without the actual key connections on it, just the teensy and TRRS/IO expander.

Anyone know where I should start checking the board for faults? I assume on the left board, near the thumbkeys… I'm thinking that there must be one place where, if bridged, it will confuse the IO expander into thinking that all the thumb keys are being held at once.

Does anyone have a full schematic of the ergodox? I haven't attempted to install software to open the pcb files yet, not sure if that will help me a huge amount with this problem anyway.

[Icarium]

Just check the keys for shorts with a multimeter. You don't really need a schematic since it is only a matrix for the keys. It just looks a little more complicated because you have left and right side on both PCBs.

[clickclack123]

Working!!!

Took all night, but I ended up desoldering every left thumb switch except one, starting at SW0:7. That wasn't the one that was the problem, I think one of the others may have had a little too much solder on it and shorted to the ground plane on the top. Installed them individually back again, testing that they weren't shorted again at every step, and it worked in the end!!

Now to get used to this crazy thing!!

[fifted]

Glad to hear it: enjoy that lovely keyboard!

[clickclack123]

Damn, seems I spoke too soon.

Last night it worked for about 3 hours, then started doing the same thing. I ended up desoldering and removing every left thumb switch again, then installed them all back. Then it worked for about 30 minutes, then started doing it again.

This is driving me crazy!! Plus I'm worried about damaging the tracks on the board from all the desoldering/resoldering. Now I'm worried that the IO Expander is flaky, although it obviously does work fine on all but one pin (the one that connects to the thumb switches).

I measured the voltage on that pin on the IO Expander, and it is about 2.2V, when all the other rows are at 5V. So it's being held lower than it should for some reason. I guess there's a short but damned if I can find it.

Stay tuned!

[tricheboars]

could it be the trrs?

[clickclack123]

could it be the trrs?

I think it's the IO Expander. I have a thread open at geekhack about it.

So, the Ergodox worked perfectly all night last night. For about 5 hours.

...Then I get home from work today, and it's not working. The pc is seeing all the left thumbkeys as being held down. I measured the red part from the diagram, and it's at 1.5-2V again!

Anyway, I'm now blaming the IO Expander. I just shorted out pin 8 of the IO Expander (the red part) with the 5V line from the TRRS cable for a second, and now the keyboard is working fine. It seems that for some reason that output line can't get to 5V without a little help!

My girlfriend just said that she can't believe that I've built a crazy keyboard that I have to jump start!

But I'm just stoked that the thing works and I don't have to spend the night soldering again.

Anyone know where I can get a replacement mcp23018 in Australia so it doesn't take too long to get here? Digi-Key Australia wants $34 for postage on a $3 part! RS Components has reasonable shipping but has a minimum order of 5.

So my fingers are firmly crossed that I will be able to jump-start it tonight.