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I've tried several Dell keyboards with the Pi, and all the ones I've tried (they're definitely not faulty, work fine elsewhere) "bounce" horribly - that is every so often it doesn't seem to detect I've released a key and will thus act like the key is being held down until another is pressed. This gets rather annoying very quickly!

A Logitech keyboard I had lying around works fine, so it's not a problem with the Pi (both Pis I have display the same behaviour.)

Is this a known problem and if so is it solvable (without changing the keyboard?)

Currently running the default Debian squeeze distribution.

  • Sounds like bad keyboard modules. Is this within xorg? – Jivings Jun 12 '12 at 22:32
  • @Jivings Both in and outside of x.org - sometimes the problem occurs when logging into the terminal which is really annoying! – berry120 Jun 12 '12 at 22:34
  • ...That is weird. +1 – Jivings Jun 12 '12 at 22:35
  • Just to cover all details can you state the distro too please. – Jivings Jun 12 '12 at 22:46
  • 1
    Key presses caught be X. It doesn't really help to diagnose the problem. – Jivings Jun 13 '12 at 14:15
8

I see the same problem with a Dell keyboard, and I believe it's down to the fact that the keyboard has a built-in USB hub. This is from the R-Pi Troubleshooting page at elinux.org:

R-Pi does not respond to key presses / Keyboard randomly repeats key presses

This is caused by inadequate power. Use a good power supply and a good power cable. Some cheap cables that work with a cell phone, cannot fully power the R-Pi. Some USB devices require a lot of power: most will have a label showing the voltage and mA requirements. They should be 5v 100mA each max, any more than this they must be used with a powered USB hub. Try unplugging every USB device except the keyboard (you should also note that some keyboards have built in hubs and can try to draw 150mA (Pi can only handle 100mA per USB slot without a hub)). Also, use the latest software. Forum user MrEngman reported some keyboard repeats and wireless hangs until upgrading to the debian6-19-04-2012 kernel, which he reports stable with no problems even with a low TP1-TP2 voltage of 4.65 - 4.68 volts.

  • I'm seeing the same with a HP keyboard - AND I have it plugged in via a powered USB hub. I may replace it with a Logitech anyway: I'd forgotten how horrible the keys felt! – winwaed Aug 23 '12 at 15:00
  • I have the same problem with Microsoft wireless keyboard and I have made my own power supply as mentioned here : elinux.org/RPi_5V_PSU_construction but it did not solve the problem at all. – M.Sameer Apr 12 '13 at 13:06

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