Author Topic: PC does not recognise USB keyboard (Read 4103 times)

glo · « **on:** Thu, 08 July 2010, 06:29:26 »

Hope for some technical help:
I was using my HHKB Lite 2 and all of a sudden it stopped working. When I tried to replug it into the USB port, XP complains the device is not recognized.
I opened it up and tried to see what went wrong but there's no sign of burnt PCB or anything.
I closed everything back and now whenever I plug it in, the computer will recognize the keyboard but after 5 or 10 minutes it stops working again.

Any ideas? Is the keyboard dead?

chimera15 · « **Reply #1 on:** Thu, 08 July 2010, 06:39:14 »

Since they have usb hubs in them they like to overvolt the hub they're plugged into. Don't use the usb plugs on the board, and make sure you're plugged into a port that has good power to it. You might want to get a powered external usb hub if you don't have one. Xp can be finicky when a device overvolts the hub recognizing it again. You have to reboot your system sometimes.

glo · « **Reply #2 on:** Thu, 08 July 2010, 06:52:16 »

Thanks chimera, I do not use its USB hub function. I even disabled it via DIP switch. I will try to remove all USB devices and try from there.

chimera15 · « **Reply #3 on:** Thu, 08 July 2010, 07:17:54 »

Or really it should be overamps I guess.

glo · « **Reply #4 on:** Thu, 08 July 2010, 07:44:16 »

Keyboard still stops working after 10 minutes or so. No other USB device was used. I'd try getting a PCI USB extension board but I'm not sure it has to do with it since other devices work without a hitch when plugged in.

microsoft windows · « **Reply #5 on:** Thu, 08 July 2010, 08:33:11 »

I bet if you got a Model M it would work more reliably than your HHKB.

chimera15 · « **Reply #6 on:** Thu, 08 July 2010, 08:41:02 »

HHkb light2's can be pretty skittish as usb keyboards. I've never had one time out like this though at a precise time. The fact that it's working though and stops, shows that it's almost certainly a power problem. You might want to try to get a ps2 adapter for it and see if it has the same symptoms being driven on the ps2 port, although I'm not 100% this will work either. Never tried that with a hhkbl2.

microsoft windows · « **Reply #7 on:** Thu, 08 July 2010, 08:42:43 »

They're 300 bucks. There's no excuse for them to be "skittish".

chimera15 · « **Reply #8 on:** Thu, 08 July 2010, 08:46:48 »

No, hhkbl2's are the cheap rubber dome variety with the bad reviews. I've mechanized 3 of mine. lol Probably like $30-60 on ebay.

You also might want to check the wiring that goes from the chip pcb to the hub pcb and make sure there's no shorting or anything.

Another problem might be that there's a short/open/wear in the usb wire, but this would only develop if you've been using it heavily. This happens with Trackball explorers for instance. The ground wires surrounding the other wires gets cut and causes an open which can cause malfunctions like this. The solution is a last resort, you cut the cord open and patch it then real the cord inside the body.

microsoft windows · « **Reply #9 on:** Thu, 08 July 2010, 08:52:02 »

Oh. I thought they were the really expensive ones.

chimera15 · « **Reply #10 on:** Thu, 08 July 2010, 08:56:23 »

The pros are the expensive ones. No usb hubs in them... At least not the first version...does the pro 2 have a usb hub? Oh yeah they do.

microsoft windows · « **Reply #11 on:** Thu, 08 July 2010, 09:16:21 »

Why does it got that mini USB port?

chimera15 · « **Reply #12 on:** Thu, 08 July 2010, 09:20:41 »

Removable cord, oh maybe not. I thought that thing on the right is dip switches, but maybe that's the removable cord....not sure.

Oh yup, that's the removable cord:

microsoft windows · « **Reply #13 on:** Thu, 08 July 2010, 09:25:13 »

That's strange.

glo · « **Reply #14 on:** Thu, 08 July 2010, 09:33:22 »

Quote from: chimera15;200637

Another problem might be that there's a short/open/wear in the usb wire, but this would only develop if you've been using it heavily. This happens with Trackball explorers for instance. The ground wires surrounding the other wires gets cut and causes an open which can cause malfunctions like this. The solution is a last resort, you cut the cord open and patch it then real the cord inside the body.

Can you give more information about this? The keyboard was actually stored for a while with the wire wrapped around it.

chimera15 · « **Reply #15 on:** Thu, 08 July 2010, 09:38:26 »

It usually happens where the wire goes into the body, where there's the most wear/stress/shear on the cord.

chimera15 · « **Reply #16 on:** Thu, 08 July 2010, 10:19:12 »

It usually only happens if there's a lot of wear. I had this happen on an old logitech keyboard of mine as well. Same symptoms, so it might be an explanation. Maybe if it had something sitting on top of it, it might have damaged the cord or something, who knows.

itlnstln · « **Reply #17 on:** Thu, 08 July 2010, 12:04:21 »

Quote from: chimera15;200650

Show Image

Quote from: microsoft windows;200651

That's strange.

From left to right:

-Outgoing USB
-Outgoing USB
-Detachable, Incoming USB
-DIP Switches (they have a cover that goes over them not seen in the pic).

microsoft windows · « **Reply #18 on:** Fri, 09 July 2010, 20:08:39 »

What's so bad about dip switches? I've got them on my printer to change its settings.

EverythingIBM · « **Reply #19 on:** Fri, 09 July 2010, 22:52:06 »

Quote from: ripster;201173

Figures you'd like DIP switches.

Show Image

ricercar · « **Reply #20 on:** Mon, 12 July 2010, 19:25:29 »

Quote from: EverythingIBM;201174

Show Image

Awesome! This image needs to be immortalized.

Quote from: microsoft windows;200636

[HHKB pro are] 300 bucks. There's no excuse for them to be "skittish".

Agreed. $300 keyboards have to be perfect.

News:

Author Topic: PC does not recognise USB keyboard (Read 4103 times)