Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.os.linux.misc > #16960 > unrolled thread

Cursor while booting

Back to article view | Back to comp.os.linux.misc

Contents

  Cursor while booting Helge <w4hw4h.hh@gmail.com> - 2016-03-12 02:54 -0800
    Re: Cursor while booting Andreas Kohlbach <march.10.ankman@spamgourmet.net> - 2016-03-12 15:08 -0500
    Re: Cursor while booting w4hw4h.hh@gmail.com - 2016-03-13 00:26 -0800
      Re: Cursor while booting William Unruh <unruh@invalid.ca> - 2016-03-13 16:26 +0000
      Re: Cursor while booting Andreas Kohlbach <march.10.ankman@spamgourmet.net> - 2016-03-13 17:05 -0400
        Re: Cursor while booting w4hw4h.hh@gmail.com - 2016-03-15 02:48 -0700
          Re: Cursor while booting Robert Heller <heller@deepsoft.com> - 2016-03-15 06:25 -0500
            Re: Cursor while booting gazelle@shell.xmission.com (Kenny McCormack) - 2016-03-15 13:32 +0000
              Re: Cursor while booting Reinhardt Behm <rbehm@hushmail.com> - 2016-03-15 22:12 +0800
              Re: Cursor while booting Robert Heller <heller@deepsoft.com> - 2016-03-15 10:48 -0500
                Re: Cursor while booting gazelle@shell.xmission.com (Kenny McCormack) - 2016-03-16 09:20 +0000
                Re: Cursor while booting Pascal Hambourg <boite-a-spam@plouf.fr.eu.org> - 2016-03-16 20:15 +0100
                  Re: Cursor while booting Keith Keller <kkeller-usenet@wombat.san-francisco.ca.us> - 2016-03-16 16:09 -0700
                    Hot-swap-ability of PS/2 devices (Was: Cursor while booting) gazelle@shell.xmission.com (Kenny McCormack) - 2016-03-17 00:31 +0000
                      Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Robert Riches <spamtrap42@jacob21819.net> - 2016-03-17 01:10 +0000
                        Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) William Unruh <unruh@invalid.ca> - 2016-03-17 05:11 +0000
                      Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Robert Heller <heller@deepsoft.com> - 2016-03-16 20:54 -0500
                        Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) William Unruh <unruh@invalid.ca> - 2016-03-17 05:13 +0000
                      Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Keith Keller <kkeller-usenet@wombat.san-francisco.ca.us> - 2016-03-17 09:37 -0700
                        Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) William Unruh <unruh@invalid.ca> - 2016-03-17 16:42 +0000
                          Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Bobbie Sellers <bliss-sf4ever@dslextreme.com> - 2016-03-17 10:02 -0700
                            Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) "Carlos E.R." <robin_listas@invalid.es> - 2016-03-17 20:11 +0100
                              Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) William Unruh <unruh@invalid.ca> - 2016-03-18 01:55 +0000
                                Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Robert Riches <spamtrap42@jacob21819.net> - 2016-03-18 03:21 +0000
                              Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) The Natural Philosopher <tnp@invalid.invalid> - 2016-03-18 12:10 +0000
                                Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) William Unruh <unruh@invalid.ca> - 2016-03-18 15:33 +0000
                                  Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) "Carlos E.R." <robin_listas@invalid.es> - 2016-03-18 20:21 +0100
                            Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) William Unruh <unruh@invalid.ca> - 2016-03-17 19:14 +0000
                              Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Bobbie Sellers <bliss-sf4ever@dslextreme.com> - 2016-03-17 13:03 -0700
                                Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) William Unruh <unruh@invalid.ca> - 2016-03-18 01:57 +0000
                                  Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Bobbie Sellers <bliss-sf4ever@dslextreme.com> - 2016-03-17 19:11 -0700
                            Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Robert Heller <heller@deepsoft.com> - 2016-03-17 14:30 -0500
                          Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Keith Keller <kkeller-usenet@wombat.san-francisco.ca.us> - 2016-03-17 14:59 -0700
                            Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Robert Heller <heller@deepsoft.com> - 2016-03-17 18:16 -0500
                              Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Keith Keller <kkeller-usenet@wombat.san-francisco.ca.us> - 2016-03-18 11:07 -0700
                                Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Robert Heller <heller@deepsoft.com> - 2016-03-18 13:49 -0500
                                  Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2016-03-18 22:13 +0000
                                Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) William Unruh <unruh@invalid.ca> - 2016-03-18 19:55 +0000
                                  Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Robert Heller <heller@deepsoft.com> - 2016-03-18 15:13 -0500
                              Re: Hot-swap-ability of PS/2 devices Andreas Kohlbach <march.10.ankman@spamgourmet.net> - 2016-03-18 14:35 -0400
                    Re: Cursor while booting Pascal Hambourg <boite-a-spam@plouf.fr.eu.org> - 2016-03-17 13:31 +0100
                      Re: Cursor while booting William Unruh <unruh@invalid.ca> - 2016-03-17 15:04 +0000
                  Hot-swap-ability of PS/2 devices (Was: Cursor while booting) gazelle@shell.xmission.com (Kenny McCormack) - 2016-03-17 00:33 +0000
                    Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) William Unruh <unruh@invalid.ca> - 2016-03-17 05:09 +0000
                      Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Aragorn <thorongil@telenet.be.invalid> - 2016-03-17 14:15 +0100
                        Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Pascal Hambourg <boite-a-spam@plouf.fr.eu.org> - 2016-03-17 15:05 +0100
        Re: Cursor while booting w4hw4h.hh@gmail.com - 2016-03-15 02:49 -0700
          Re: Cursor while booting w4hw4h.hh@gmail.com - 2016-03-15 02:57 -0700
    Re: Cursor while booting Teemu Likonen <tlikonen@iki.fi> - 2016-03-13 11:36 +0200
      Re: Cursor while booting w4hw4h.hh@gmail.com - 2016-03-15 02:47 -0700
        Re: Cursor while booting William Unruh <unruh@invalid.ca> - 2016-03-15 19:45 +0000
      Re: Cursor while booting w4hw4h.hh@gmail.com - 2016-03-15 02:53 -0700
        Re: Cursor while booting The Natural Philosopher <tnp@invalid.invalid> - 2016-03-15 10:02 +0000
    Re: Cursor while booting Chick Tower <c.tower@deadspam.com> - 2016-03-15 16:52 +0000

Page 1 of 3  [1] 2 3  Next page →

#16960 — Cursor while booting

Linux Ubuntu 12.04
2 partitions: Windows XP, Linux 12.04
For some reason the cursor is no longer active during boot. So I can't select WiXP to be booted. Both partitions are flagged as bootable.
How to reactivate the cursor while booting the system?

[toc] | [next] | [standalone]

#16961

Helge wrote on 12. March 2016:
>
> Linux Ubuntu 12.04
> 2 partitions: Windows XP, Linux 12.04
> For some reason the cursor is no longer active during boot. So I can't select WiXP to be booted. Both partitions are flagged as bootable.
> How to reactivate the cursor while booting the system?

Do you mean the boot menu doesn't show up? If, press and hold any key
right after the BIOS message has gone. With some luck it should drop you
into the boot menu.

Assuming GRUB and having root access, have a look into /etc/default/grub
and find

GRUB_TIMEOUT=

and put the number in seconds after the "=" you want it to wait before
booting the default OS. Run "update-grub" after that.
-- 
Andreas

I use a Unix based operating system, which means I get laid almost as often
as I have to reboot my computer.

[toc] | [prev] | [next] | [standalone]

#16965

Am Samstag, 12. März 2016 11:54:56 UTC+1 schrieb Helge:
> Linux Ubuntu 12.04
> 2 partitions: Windows XP, Linux 12.04
> For some reason the cursor is no longer active during boot. So I can't select WiXP to be booted. Both partitions are flagged as bootable.
> How to reactivate the cursor while booting the system?

No. The boot menu shows up for 10s (GRUB_TIMEOUT=10) but I can't move the cursor within the menu to select one of the four options. The cursor is not present.
Helge

[toc] | [prev] | [next] | [standalone]

#16969

On 2016-03-13, w4hw4h.hh@gmail.com <w4hw4h.hh@gmail.com> wrote:
> Am Samstag, 12. M?rz 2016 11:54:56 UTC+1 schrieb Helge:
>> Linux Ubuntu 12.04
>> 2 partitions: Windows XP, Linux 12.04
>> For some reason the cursor is no longer active during boot. So I can't select WiXP to be booted. Both partitions are flagged as bootable.
>> How to reactivate the cursor while booting the system?
>
> No. The boot menu shows up for 10s (GRUB_TIMEOUT=10) but I can't move the cursor within the menu to select one of the four options. The cursor is not present.
> Helge

So what happens if you use the arrow keys. Can you select which menu
item to boot with the arrow keys?
>

[toc] | [prev] | [next] | [standalone]

#16974

w4hw4h.hh@gmail.com wrote on 13. March 2016:
>
> Am Samstag, 12. März 2016 11:54:56 UTC+1 schrieb Helge:
>> Linux Ubuntu 12.04 2 partitions: Windows XP, Linux 12.04 For some
>> reason the cursor is no longer active during boot. So I can't select
>> WiXP to be booted. Both partitions are flagged as bootable.  How to
>> reactivate the cursor while booting the system?
>
> No. The boot menu shows up for 10s (GRUB_TIMEOUT=10) but I can't move
> the cursor within the menu to select one of the four options. The
> cursor is not present.

Are you using an USB or Bluetooth keyboard?
-- 
Andreas

I use a Unix based operating system, which means I get laid almost as often
as I have to reboot my computer.

[toc] | [prev] | [next] | [standalone]

#16989

Am Sonntag, 13. März 2016 22:05:45 UTC+1 schrieb Andreas Kohlbach:
> w4hw4h.hh@gmail.com wrote on 13. March 2016:
> >
> > Am Samstag, 12. März 2016 11:54:56 UTC+1 schrieb Helge:
> >> Linux Ubuntu 12.04 2 partitions: Windows XP, Linux 12.04 For some
> >> reason the cursor is no longer active during boot. So I can't select
> >> WiXP to be booted. Both partitions are flagged as bootable.  How to
> >> reactivate the cursor while booting the system?
> >
> > No. The boot menu shows up for 10s (GRUB_TIMEOUT=10) but I can't move
> > the cursor within the menu to select one of the four options. The
> > cursor is not present.
> 
> Are you using an USB or Bluetooth keyboard?

Keyboard is used via PS2.

> -- 
> Andreas
> 
> I use a Unix based operating system, which means I get laid almost as often
> as I have to reboot my computer.

[toc] | [prev] | [next] | [standalone]

#16994

At Tue, 15 Mar 2016 02:48:41 -0700 (PDT) w4hw4h.hh@gmail.com wrote:

> 
> Am Sonntag, 13. M=E4rz 2016 22:05:45 UTC+1 schrieb Andreas Kohlbach:
> > w4hw4h.hh@gmail.com wrote on 13. March 2016:
> > >
> > > Am Samstag, 12. M=E4rz 2016 11:54:56 UTC+1 schrieb Helge:
> > >> Linux Ubuntu 12.04 2 partitions: Windows XP, Linux 12.04 For some
> > >> reason the cursor is no longer active during boot. So I can't select
> > >> WiXP to be booted. Both partitions are flagged as bootable.  How to
> > >> reactivate the cursor while booting the system?
> > >
> > > No. The boot menu shows up for 10s (GRUB_TIMEOUT=3D10) but I can't move
> > > the cursor within the menu to select one of the four options. The
> > > cursor is not present.
> >=20
> > Are you using an USB or Bluetooth keyboard?
> 
> Keyboard is used via PS2.

Did you plug the keyboard into the PS/2 mouse port by mistake?

> 
> > --=20
> > Andreas
> >=20
> > I use a Unix based operating system, which means I get laid almost as oft=
> en
> > as I have to reboot my computer.
> 
>                                                                                                                

-- 
Robert Heller             -- 978-544-6933
Deepwoods Software        -- Custom Software Services
http://www.deepsoft.com/  -- Linux Administration Services
heller@deepsoft.com       -- Webhosting Services
                                                                                         

[toc] | [prev] | [next] | [standalone]

#16998

In article <l5adna1O3JmjbHrLnZ2dnUU7-avNnZ2d@giganews.com>,
Robert Heller  <heller@deepsoft.com> wrote:
...
>> Keyboard is used via PS2.
>
>Did you plug the keyboard into the PS/2 mouse port by mistake?

Good point.

Also, make sure the computer is plugged in and that you've paid your
electric bill.

-- 
The last time a Republican cared about you, you were a fetus.

[toc] | [prev] | [next] | [standalone]

#16999

Kenny McCormack wrote:

> In article <l5adna1O3JmjbHrLnZ2dnUU7-avNnZ2d@giganews.com>,
> Robert Heller  <heller@deepsoft.com> wrote:
> ...
>>> Keyboard is used via PS2.
>>
>>Did you plug the keyboard into the PS/2 mouse port by mistake?
> 
> Good point.
> 
> Also, make sure the computer is plugged in and that you've paid your
> electric bill.

Is it a computer?
 
-- 
Reinhardt

[toc] | [prev] | [next] | [standalone]

#17000

At Tue, 15 Mar 2016 13:32:00 +0000 (UTC) gazelle@shell.xmission.com (Kenny McCormack) wrote:

> 
> In article <l5adna1O3JmjbHrLnZ2dnUU7-avNnZ2d@giganews.com>,
> Robert Heller  <heller@deepsoft.com> wrote:
> ...
> >> Keyboard is used via PS2.
> >
> >Did you plug the keyboard into the PS/2 mouse port by mistake?
> 
> Good point.
> 
> Also, make sure the computer is plugged in and that you've paid your
> electric bill.
> 

I was actually serious. Computers with PS/2 ports have two and both are the
*same* sort of connector (usually colored differently, but earlier machines
did not color the connectors differently). It is really a *common* mistake
(even *I* have done it) to plug the mouse into the keyboard and keyboard into
the mouse port. This does not always work (and sometimes it does). It is also
important to completely reboot the machine when you plug in PS/2 devices --
the PS/2 ports are *NOT* 'hot swappable' (USB ports ARE 'hot swappable').

-- 
Robert Heller             -- 978-544-6933
Deepwoods Software        -- Custom Software Services
http://www.deepsoft.com/  -- Linux Administration Services
heller@deepsoft.com       -- Webhosting Services
                

[toc] | [prev] | [next] | [standalone]

#17013

In article <xcqdnZcb6MJYs3XLnZ2dnUU7-aPNnZ2d@giganews.com>,
Robert Heller  <heller@deepsoft.com> wrote:
...
>> Also, make sure the computer is plugged in and that you've paid your
>> electric bill.
>> 
>
>I was actually serious.

What makes you think I wasn't?  I've certainly made the mistake of
forgetting to plug it in.  Luckily, I'm not in charge of paying the bills
around here, so have never made the second mistake alluded to above.

>Computers with PS/2 ports have two and both are the
>*same* sort of connector (usually colored differently, but earlier machines
>did not color the connectors differently).

I've got such a machine here.  It's really old, but the connectors are
color coded.  I think you'd have to go back to the 80s to find one that
isn't.

>It is really a *common* mistake (even *I* have done it) to plug the mouse
>into the keyboard and keyboard into the mouse port. This does not always
>work (and sometimes it does). It is also important to completely reboot
>the machine when you plug in PS/2 devices -- the PS/2 ports are *NOT* 'hot
>swappable' (USB ports ARE 'hot swappable').

All true.

-- 
Just for a change of pace, this sig is *not* an obscure reference to
comp.lang.c...

[toc] | [prev] | [next] | [standalone]

#17026

Robert Heller a écrit :
> 
> It is also
> important to completely reboot the machine when you plug in PS/2 devices --

No. It is important to *power off* the machine before plugging or
unplugging PS/2 devices.

> the PS/2 ports are *NOT* 'hot swappable' (USB ports ARE 'hot swappable').

Indeed. You can even fry a PS/2 port or device if you plug or unplug it
while the power is on.

[toc] | [prev] | [next] | [standalone]

#17027

On 2016-03-16, Pascal Hambourg <boite-a-spam@plouf.fr.eu.org> wrote:
>
> Indeed. You can even fry a PS/2 port or device if you plug or unplug it
> while the power is on.

I know this is true in theory, but I have plugged/unplugged PS/2 devices
with the power on probably hundreds of times over the past 20 years, and
have had one device and one port fry in that time (in unrelated separate
incidents).  If you can power down, great.  If not, the risk is low,
just be very very sure that you can make alternate arrangements in case
you do fry something.

--keith


-- 
kkeller-usenet@wombat.san-francisco.ca.us
(try just my userid to email me)
AOLSFAQ=http://www.therockgarden.ca/aolsfaq.txt
see X- headers for PGP signature information

[toc] | [prev] | [next] | [standalone]

#17029 — Hot-swap-ability of PS/2 devices (Was: Cursor while booting)

In article <ol5prcxops.ln2@goaway.wombat.san-francisco.ca.us>,
Keith Keller  <kkeller-usenet@wombat.san-francisco.ca.us> wrote:
...
>> Indeed. You can even fry a PS/2 port or device if you plug or unplug it
>> while the power is on.
...
>I know this is true in theory, but I have plugged/unplugged PS/2 devices
>with the power on probably hundreds of times over the past 20 years, and
>have had one device and one port fry in that time (in unrelated separate
>incidents).  If you can power down, great.  If not, the risk is low,
>just be very very sure that you can make alternate arrangements in case
>you do fry something.

Yeah, I was about to question the, er, if not veracity, shall we say,
relevance of the previous poster's post.  I'd like to know if he could say
more about what conditions (actions) would actually cause the noted
"frying".  My guess is that it would be if you "bounced" the connection -
that is, sorta made contact, then broke contact, etc - enough times (and in
just the "right" way).

I say all this because, back in the day, I had a PS/2 KVM at my office
desk, switching happily between several computers.  Obviously, this was
hot-swapping a PS/2 mouse and PS/2 keyboard around, and it all worked fine.
I'm sure this was because the makers of the KVM knew what they were doing
and knew how to do it safely.  Nowadays, we all have USB KVMs, of course,
but those were the days...

So, in conclusion, it seems pretty clear that the previous poster's advice
was much more in the category of "This is what we must tell beginners" than
in the "This is what is actually true" category.

-- 
http://www.xmission.com/~gazelle/BestCLCPostEver

[toc] | [prev] | [next] | [standalone]

#17031 — Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting)

On 2016-03-17, Kenny McCormack <gazelle@shell.xmission.com> wrote:
> In article <ol5prcxops.ln2@goaway.wombat.san-francisco.ca.us>,
> Keith Keller  <kkeller-usenet@wombat.san-francisco.ca.us> wrote:
> ...
>>> Indeed. You can even fry a PS/2 port or device if you plug or unplug it
>>> while the power is on.
> ...
>>I know this is true in theory, but I have plugged/unplugged PS/2 devices
>>with the power on probably hundreds of times over the past 20 years, and
>>have had one device and one port fry in that time (in unrelated separate
>>incidents).  If you can power down, great.  If not, the risk is low,
>>just be very very sure that you can make alternate arrangements in case
>>you do fry something.
>
> Yeah, I was about to question the, er, if not veracity, shall we say,
> relevance of the previous poster's post.  I'd like to know if he could say
> more about what conditions (actions) would actually cause the noted
> "frying".  My guess is that it would be if you "bounced" the connection -
> that is, sorta made contact, then broke contact, etc - enough times (and in
> just the "right" way).
>
> I say all this because, back in the day, I had a PS/2 KVM at my office
> desk, switching happily between several computers.  Obviously, this was
> hot-swapping a PS/2 mouse and PS/2 keyboard around, and it all worked fine.
> I'm sure this was because the makers of the KVM knew what they were doing
> and knew how to do it safely.  Nowadays, we all have USB KVMs, of course,
> but those were the days...
>
> So, in conclusion, it seems pretty clear that the previous poster's advice
> was much more in the category of "This is what we must tell beginners" than
> in the "This is what is actually true" category.

Switching PS/2 keyboard and mouse with a properly designed KVM is
not necessarily the same thing as physically [un]plugging the
connectors.  The KVM might have active circuitry inside to do the
switching with controlled logic levels.  Even if the KVM was
entirely passive, it could have had Rs, Cs, and maybe Ls to keep
the transient voltages at the instance of switching to reasonable
levels.  The KVM's switch or relay contacts could also be
designed to minimize transients.

While it's not the same thing as a PS/2 port, you can give
yourself a nice little zap with a 9V battery and a _single_
winding of a power or audio transformer (or even a simple choke)
via inductive kick.  You'll get voltages _way_ over 9V.

For another illustration, old-style (1970ish) automotive ignition
systems used inductive kick to transform 12V into a 400V
transient on the _primary_ side of the ignition coil.

-- 
Robert Riches
spamtrap42@jacob21819.net
(Yes, that is one of my email addresses.)

[toc] | [prev] | [next] | [standalone]

#17034 — Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting)

On 2016-03-17, Robert Riches <spamtrap42@jacob21819.net> wrote:
> On 2016-03-17, Kenny McCormack <gazelle@shell.xmission.com> wrote:
>> In article <ol5prcxops.ln2@goaway.wombat.san-francisco.ca.us>,
>> Keith Keller  <kkeller-usenet@wombat.san-francisco.ca.us> wrote:
>
> While it's not the same thing as a PS/2 port, you can give
> yourself a nice little zap with a 9V battery and a _single_
> winding of a power or audio transformer (or even a simple choke)
> via inductive kick.  You'll get voltages _way_ over 9V.

Yes, and mice and keyboards are know for the huge inductors all of the
place in them. 

>
> For another illustration, old-style (1970ish) automotive ignition
> systems used inductive kick to transform 12V into a 400V
> transient on the _primary_ side of the ignition coil.

And shoes on carpets produce thousands of volts. 
>

[toc] | [prev] | [next] | [standalone]

#17032 — Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting)

At Thu, 17 Mar 2016 00:31:40 +0000 (UTC) gazelle@shell.xmission.com (Kenny McCormack) wrote:

> 
> In article <ol5prcxops.ln2@goaway.wombat.san-francisco.ca.us>,
> Keith Keller  <kkeller-usenet@wombat.san-francisco.ca.us> wrote:
> ...
> >> Indeed. You can even fry a PS/2 port or device if you plug or unplug it
> >> while the power is on.
> ...
> >I know this is true in theory, but I have plugged/unplugged PS/2 devices
> >with the power on probably hundreds of times over the past 20 years, and
> >have had one device and one port fry in that time (in unrelated separate
> >incidents).  If you can power down, great.  If not, the risk is low,
> >just be very very sure that you can make alternate arrangements in case
> >you do fry something.
> 
> Yeah, I was about to question the, er, if not veracity, shall we say,
> relevance of the previous poster's post.  I'd like to know if he could say
> more about what conditions (actions) would actually cause the noted
> "frying".  My guess is that it would be if you "bounced" the connection -
> that is, sorta made contact, then broke contact, etc - enough times (and in
> just the "right" way).
> 
> I say all this because, back in the day, I had a PS/2 KVM at my office
> desk, switching happily between several computers.  Obviously, this was
> hot-swapping a PS/2 mouse and PS/2 keyboard around, and it all worked fine.
> I'm sure this was because the makers of the KVM knew what they were doing
> and knew how to do it safely.  Nowadays, we all have USB KVMs, of course,
> but those were the days...

My guess is the KVM switch had enough inner 'logic' to cause the 'diconnected' 
machine to believe a keyboard & mouse were in fact still connected.

> 
> So, in conclusion, it seems pretty clear that the previous poster's advice
> was much more in the category of "This is what we must tell beginners" than
> in the "This is what is actually true" category.

Oh, it is really true.  If the PS/2 keyboard or mouse is not plugged in at 
boot time, it *will not work* if plugged in later.  *Really*.  If your PS/2 
mouse or keyboard dies, *you must reboot* when you replace it.

USB mice/keyboards can be swapped amoungst live running computers with totall
impunity.

> 

-- 
Robert Heller             -- 978-544-6933
Deepwoods Software        -- Custom Software Services
http://www.deepsoft.com/  -- Linux Administration Services
heller@deepsoft.com       -- Webhosting Services
                                                                                                                            

[toc] | [prev] | [next] | [standalone]

#17035 — Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting)

On 2016-03-17, Robert Heller <heller@deepsoft.com> wrote:
> At Thu, 17 Mar 2016 00:31:40 +0000 (UTC) gazelle@shell.xmission.com (Kenny McCormack) wrote:
>
>> 
>> In article <ol5prcxops.ln2@goaway.wombat.san-francisco.ca.us>,
>> Keith Keller  <kkeller-usenet@wombat.san-francisco.ca.us> wrote:
>> ...
>> >> Indeed. You can even fry a PS/2 port or device if you plug or unplug it
>> >> while the power is on.
>> ...
>> >I know this is true in theory, but I have plugged/unplugged PS/2 devices
>> >with the power on probably hundreds of times over the past 20 years, and
>> >have had one device and one port fry in that time (in unrelated separate
>> >incidents).  If you can power down, great.  If not, the risk is low,
>> >just be very very sure that you can make alternate arrangements in case
>> >you do fry something.
>> 
>> Yeah, I was about to question the, er, if not veracity, shall we say,
>> relevance of the previous poster's post.  I'd like to know if he could say
>> more about what conditions (actions) would actually cause the noted
>> "frying".  My guess is that it would be if you "bounced" the connection -
>> that is, sorta made contact, then broke contact, etc - enough times (and in
>> just the "right" way).
>> 
>> I say all this because, back in the day, I had a PS/2 KVM at my office
>> desk, switching happily between several computers.  Obviously, this was
>> hot-swapping a PS/2 mouse and PS/2 keyboard around, and it all worked fine.
>> I'm sure this was because the makers of the KVM knew what they were doing
>> and knew how to do it safely.  Nowadays, we all have USB KVMs, of course,
>> but those were the days...
>
> My guess is the KVM switch had enough inner 'logic' to cause the 'diconnected' 
> machine to believe a keyboard & mouse were in fact still connected.
>
>> 
>> So, in conclusion, it seems pretty clear that the previous poster's advice
>> was much more in the category of "This is what we must tell beginners" than
>> in the "This is what is actually true" category.
>
> Oh, it is really true.  If the PS/2 keyboard or mouse is not plugged in at 
> boot time, it *will not work* if plugged in later.  *Really*.  If your PS/2 
> mouse or keyboard dies, *you must reboot* when you replace it.
>
> USB mice/keyboards can be swapped amoungst live running computers with totall
> impunity.

Yup. I guess I better hope that this message does not get transmitted to
my keyboard and mouse, since I just hot swapped then and they work. Must
be imagining things. 

>
>> 
>

[toc] | [prev] | [next] | [standalone]

#17045 — Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting)

On 2016-03-17, Kenny McCormack <gazelle@shell.xmission.com> wrote:
> In article <ol5prcxops.ln2@goaway.wombat.san-francisco.ca.us>,
> Keith Keller  <kkeller-usenet@wombat.san-francisco.ca.us> wrote:
> ...
>>I know this is true in theory, but I have plugged/unplugged PS/2 devices
>>with the power on probably hundreds of times over the past 20 years, and
>>have had one device and one port fry in that time (in unrelated separate
>>incidents).  If you can power down, great.  If not, the risk is low,
>>just be very very sure that you can make alternate arrangements in case
>>you do fry something.

> So, in conclusion, it seems pretty clear that the previous poster's advice
> was much more in the category of "This is what we must tell beginners" than
> in the "This is what is actually true" category.

It is really true; as I said, the incidence of failures I have seen is
definitely nonzero, and the connectors were definitely not made to be
hot-plugged.

--keith

-- 
kkeller-usenet@wombat.san-francisco.ca.us
(try just my userid to email me)
AOLSFAQ=http://www.therockgarden.ca/aolsfaq.txt
see X- headers for PGP signature information

[toc] | [prev] | [next] | [standalone]

#17046 — Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting)

On 2016-03-17, Keith Keller <kkeller-usenet@wombat.san-francisco.ca.us> wrote:
> On 2016-03-17, Kenny McCormack <gazelle@shell.xmission.com> wrote:
>> In article <ol5prcxops.ln2@goaway.wombat.san-francisco.ca.us>,
>> Keith Keller  <kkeller-usenet@wombat.san-francisco.ca.us> wrote:
>> ...
>>>I know this is true in theory, but I have plugged/unplugged PS/2 devices
>>>with the power on probably hundreds of times over the past 20 years, and
>>>have had one device and one port fry in that time (in unrelated separate
>>>incidents).  If you can power down, great.  If not, the risk is low,
>>>just be very very sure that you can make alternate arrangements in case
>>>you do fry something.
>
>> So, in conclusion, it seems pretty clear that the previous poster's advice
>> was much more in the category of "This is what we must tell beginners" than
>> in the "This is what is actually true" category.
>
> It is really true; as I said, the incidence of failures I have seen is
> definitely nonzero, and the connectors were definitely not made to be
> hot-plugged.
>

Well, there are two questions, one is whether plugging something in/out
destroys something, or whether the hardware does not report anything to
the system that something has been plugged in/out. The former is a case
of completely incompetent engineering if it is the case. Anything that
is plugged in could be disconnected by accident or even
connected/disconnected repeatedly by a loose contact, and if it is not
engineered to take that, it is incompetent engineering. I am of course
not saying that incompetent engineering does not occur, but it is surely
not the norm. 

[toc] | [prev] | [next] | [standalone]

Page 1 of 3  [1] 2 3  Next page →

Back to top | Article view | comp.os.linux.misc

csiph-web