#5658 NORM Ship.2: Sticky Alt or Control Key

[Zarro Boogs per Child]

#5658: Sticky Alt or Control Key
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  Reporter:  davidpfarrell  |       Owner:  wad      
      Type:  defect         |      Status:  new      
  Priority:  normal         |   Milestone:  Ship.2   
 Component:  hardware       |     Version:  Build 650
Resolution:                 |    Keywords:           
  Verified:  0              |    Blocking:           
 Blockedby:                 |  
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Comment(by joemck):

 Writing this from an XO that had a stuck Ctrl key yesterday. The key was
 only stuck sometimes, and almost always registered a press when the left
 shift or A were pressed. Ctrl was also over-sensitive -- just barely
 touching the key would register.

 It is indeed a hardware problem.  It seems that part of the frame around
 the keyboard presses down and inward on the edge of the rubber membrane.
 I took apart the bottom part of my XO, reassembled it, and the problem was
 still there.  Then I took it apart again, ran the OFW keyboard diagnostic
 with it open, messed with the edge of the frame, saw that it's what's
 causing the problem, then started putting it back together to see what
 part made it start messing up when I put it in.  I got the whole thing
 back together without any stuck keys, so I'm not entirely sure exactly
 what part was causing the problem.

 If you have stuck-key problems, I suggest pressing the thin left edge of
 the white keyboard frame outward into the green rail.

 ...There's also a separate problem mentioned in this thread: Quickly
 pressing and releasing a key occasionally leaves it in the "pressed"
 state. Pressing it again unsticks it. This is probably a hardware problem
 caused by how the keys get scanned. It may be possible to fix it in the
 OFW, though I'm not familiar with the keyboard interface. (Is it currently
 being polled at all? What's the update frequency?) Also, mashing multiple
 keys doesn't make all of them register, and often makes one become
 temporarily stuck.

-- 
Ticket URL: <http://dev.laptop.org/ticket/5658#comment:41>
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