[comp.unix.microport] Keyboard Lockup in Scroll

lindsay@dscatl.UUCP (Lindsay Cleveland) (11/02/88)

In article <1545@viper.Lynx.MN.Org> dave@viper.Lynx.MN.Org (David Messer) writes:
>In article <319@sdti.UUCP> mjy@sdti.UUCP (Michael J. Young) writes:
> >4.  Sometimes the keyboard locks up (scroll lock light on) and there
> >    doesn't seem to be a way to free it up short of reset.  Even Ctrl-Alt-Del
> >    stops working.  It's happened to me three times in four days, usually when
> >    I've accidentally hit more than one key at a time while using CTRL-S
> >    and CTRL-Q.  This never happened under 2.3, even though I wasn't
> >    any better a typist back then!
>
>I've had this happen several times also with the same
>symptoms.  When it happened I was both changing screens
>rapidly with the "hot" keys and beating the disks with my
>test.  Perhaps they are losing interrupts on the keyboard
>driver?
>

While I don't have answers, I have a indication and a work-around.

I have a system has the same symptom.  It is an AT clone with a
"Turbo Switch" which allows me to vary the clock speed.  I find that
at the higher speeds (Norton index > 5), some keyboards will *always*
lock up when one is rapidly hitting the keys, while others will
not.  The same keyboards that give this problem also cause the
"Keyboard Error...Press F1 to Continue" message to appear during
a cold-boot.  However, at lower clock speeds, no problems occur.

The suspicion is the difference in the performance of the IC chip
in various keyboards.  My work-around for a lock-up is to disconnect the
keyboard for about 10 seconds, and plug it back in; then
do CNTL-Q.  It will crank back up 90% of the time.  Pressing
"Scroll Lock" usually does *not* get it going again, but CNTL-Q does.

Additional symptom...the keyboards that lock up also do not light
the "caps lock", "num lock", or "scroll lock" indicators at the
higher clock speed, yet they control them properly at the lower
speeds.

Cheers,
  Lindsay

Lindsay Cleveland         Digital Systems Co.   Atlanta, Ga
  gatech!dscatl!lindsay     (404) 497-1902
                         (U.S. Mail:  PO Box 1140, Duluth, GA  30136)