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-   -   Why do we have to keep rebooting things? (http://www.homecinemabanter.com/showthread.php?t=67530)

[email protected] September 28th 10 02:51 AM

Why do we have to keep rebooting things?
 
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot? Couldn't satellite receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the same
channel of course?).

Bill

Roderick Stewart[_2_] September 28th 10 06:55 AM

Why do we have to keep rebooting things?
 
In article de898962-6535-4431-9faa-
,
wrote:
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot? Couldn't satellite receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the same
channel of course?).


It would need software to detect the problem and make the decision to do
this - but it's usually software that is the cause of the problem in the
first place. Catch 22.

There's no substitute for a brain, and a finger on a button.

Or a big hammer.

Rod.
--
Virtual Access V6.3 free usenet/email software from
http://sourceforge.net/projects/virtual-access/


Woody[_3_] September 28th 10 08:43 AM

Why do we have to keep rebooting things?
 
" wrote in
message
...
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How
come? Why
don't they make these things so that when they're incapable of
doing
their job they just automatically reboot? Couldn't satellite
receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the
same
channel of course?).

Bill



You can actually make Windoze do that - but if it then detects a
problem during any subsequent boot-up it will keep restarting
itself ad infinitum.


--
Woody

harrogate three at ntlworld dot com



Paul D Smith[_2_] September 28th 10 09:49 AM

Why do we have to keep rebooting things?
 
" wrote in message
...
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot? Couldn't satellite receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the same
channel of course?).

Bill


You need to talk to some telecoms people. Telecoms require around 6-9s
reliability (i.e. dial-tone 99.9999% of the time - work out how many seconds
a year you can be "down").

Actually this is incredibly difficult using modern software because as
others have said, there is just so much of it and it can go wrong in so may
ways. For example consider the following code...

if (it's monday)
{
if (coronation street is on)
{
record it (1)
}
else
{
wait... (2)
}
else if (eastenders is on)
{
record it (3)
}
else
{
do something else (4)
}

There are 4 different blocks of "code" to test. Now software has 1000s of
such blocks and unlike in this case, they are often not independent. Think
perhaps of some code which does something if Coronation Street is on, or
East Enders, or both. You might think that these would be independent but
the programs are on different MUXs so two tuning operations not one, and
what if you're watching a third Mux? Oh, and you only have one hard disk to
record onto so the two recordings have to share - you get the idea!

So for something like a PVR, if things do go wrong it's far better to leave
the smartest device in the room (normally), i.e. the owner to decide what to
do next rather than take a guess which might be totally the wrong thing to
do.

For example if my PVR locks up, as it has done occasionally, I never reboot
until after the "thing it should be recording" has finished. Sometimes it
makes no difference but sometimes it actually is recording even though it's
not responding to commands.

Of course with telecoms there isn't that luxury but then we would be talking
of powerful boxes costing a large amount of money and the cost of specialist
hardware and the like can be justified.

So, all down to bangs per buck. If all you want is something that does all
that a video recorder can then fine, but PVRs do far, far, more and for far
less cost these days - but you get what you pay for.

Paul DS



Andy Burns[_7_] September 28th 10 09:58 AM

Why do we have to keep rebooting things?
 
wrote:

Couldn't satellite receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the same
channel of course?).


My sony IDTV used to do just that, bloody thing; might only have
happened once every few months, but always at the wrong moment.

Andy Burns[_7_] September 28th 10 10:02 AM

Why do we have to keep rebooting things?
 
Roderick Stewart wrote:

It would need software to detect the problem and make the decision to do
this - but it's usually software that is the cause of the problem in the
first place. Catch 22.


Sometimes the watchdog approach does work, so long as it is taken by the
developer as a sign that there is a problem rather than that it is the cure.

pete September 28th 10 10:09 AM

Why do we have to keep rebooting things?
 
On Tue, 28 Sep 2010 05:55:03 +0100, Roderick Stewart wrote:
In article de898962-6535-4431-9faa-
,
wrote:
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot? Couldn't satellite receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the same
channel of course?).


It would need software to detect the problem and make the decision to do
this - but it's usually software that is the cause of the problem in the
first place. Catch 22.

What you're asking is commonplace in embedded software. it's known as a
watchdog timer and is implemented in hardware. Briefly, every few
seconds a hardware reset is sent to the processor _unless_ in the
preceeding time it has been cancelled by code in the main programme
that says "it's OK, I'm still running normally" - at which point the
countdown to the next hardware reset starts again.

So far as consumer electronics goes, the reason it fails is because
it's not very well written. Often due to time constraints on the
developers (or lack of a decent specification, or last-minute changes)
or cheapness in the hardware or plain ineptitude - though often the
root cause is a combination of all of these.

Just be gald that stuff which really counts, such as the engine
management unit in your car is written to professional standards
and is rigorously tested (well, usually) to a much higher standard.

--
http://www.thisreallyismyhost.99k.or...9011619151.php

bugbear September 28th 10 10:28 AM

Why do we have to keep rebooting things?
 
wrote:
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot?


I read a wonderful piece of problem analysis/engineering design.

A team of programmers were working on an engine management system.
Now a car engine is a lousy place to put a computer; it's full
of vibration, noise and high frequency, high voltage electricity.

No matter how many fixes they added to the EMS they simply couldn't
make it run for more than a few minutes before it crashed.

And the cost of the EMS was spirally with all the "bomb proofing"
they were adding.

The eventual solution?

Solve a different problem.

They put a lot of effort into making the EMS boot up nearly
instantaneously, and rebooted it (from a simple timer)
every couple of seconds!

BugBear

Paul Ratcliffe September 28th 10 10:39 AM

Why do we have to keep rebooting things?
 
On Tue, 28 Sep 2010 08:49:59 +0100, Paul D Smith
wrote:

Actually this is incredibly difficult using modern software because as
others have said, there is just so much of it and it can go wrong in so may
ways. For example consider the following code...

if (it's monday)
{
if (coronation street is on)
{
record it (1)
}
else
{
wait... (2)
}
else if (eastenders is on)
{
record it (3)
}
else
{
do something else (4)
}


Oh the irony. Syntax error: mismatched braces. Computer went bang.
This post was inadequately tested before the Send operation was initiated.

Brian Gaff September 28th 10 10:48 AM

Why do we have to keep rebooting things?
 
So Clive Sinclairs claim that a nuclear power station could run on a zx81 is
a little irrisponsible then.
Brian

--
Brian Gaff -
Note:- In order to reduce spam, any email without 'Brian Gaff'
in the display name may be lost.
Blind user, so no pictures please!
"pete" wrote in message
...
On Tue, 28 Sep 2010 05:55:03 +0100, Roderick Stewart wrote:
In article de898962-6535-4431-9faa-
,
wrote:
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot? Couldn't satellite receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the same
channel of course?).


It would need software to detect the problem and make the decision to do
this - but it's usually software that is the cause of the problem in the
first place. Catch 22.

What you're asking is commonplace in embedded software. it's known as a
watchdog timer and is implemented in hardware. Briefly, every few
seconds a hardware reset is sent to the processor _unless_ in the
preceeding time it has been cancelled by code in the main programme
that says "it's OK, I'm still running normally" - at which point the
countdown to the next hardware reset starts again.

So far as consumer electronics goes, the reason it fails is because
it's not very well written. Often due to time constraints on the
developers (or lack of a decent specification, or last-minute changes)
or cheapness in the hardware or plain ineptitude - though often the
root cause is a combination of all of these.

Just be gald that stuff which really counts, such as the engine
management unit in your car is written to professional standards
and is rigorously tested (well, usually) to a much higher standard.

--
http://www.thisreallyismyhost.99k.or...9011619151.php




Brian Gaff September 28th 10 10:52 AM

Why do we have to keep rebooting things?
 
Of course there is always the multiple computer approach as used in aviation
where several systems work together and the moment one of these disagrees
its voted off and rebooted.
Brian

--
Brian Gaff -
Note:- In order to reduce spam, any email without 'Brian Gaff'
in the display name may be lost.
Blind user, so no pictures please!
"Paul D Smith" wrote in message
...
" wrote in message
...
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot? Couldn't satellite receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the same
channel of course?).

Bill


You need to talk to some telecoms people. Telecoms require around 6-9s
reliability (i.e. dial-tone 99.9999% of the time - work out how many
seconds a year you can be "down").

Actually this is incredibly difficult using modern software because as
others have said, there is just so much of it and it can go wrong in so
may ways. For example consider the following code...

if (it's monday)
{
if (coronation street is on)
{
record it (1)
}
else
{
wait... (2)
}
else if (eastenders is on)
{
record it (3)
}
else
{
do something else (4)
}

There are 4 different blocks of "code" to test. Now software has 1000s of
such blocks and unlike in this case, they are often not independent.
Think perhaps of some code which does something if Coronation Street is
on, or East Enders, or both. You might think that these would be
independent but the programs are on different MUXs so two tuning
operations not one, and what if you're watching a third Mux? Oh, and you
only have one hard disk to record onto so the two recordings have to
share - you get the idea!

So for something like a PVR, if things do go wrong it's far better to
leave the smartest device in the room (normally), i.e. the owner to decide
what to do next rather than take a guess which might be totally the wrong
thing to do.

For example if my PVR locks up, as it has done occasionally, I never
reboot until after the "thing it should be recording" has finished.
Sometimes it makes no difference but sometimes it actually is recording
even though it's not responding to commands.

Of course with telecoms there isn't that luxury but then we would be
talking of powerful boxes costing a large amount of money and the cost of
specialist hardware and the like can be justified.

So, all down to bangs per buck. If all you want is something that does
all that a video recorder can then fine, but PVRs do far, far, more and
for far less cost these days - but you get what you pay for.

Paul DS





Ian Jackson[_2_] September 28th 10 10:59 AM

Why do we have to keep rebooting things?
 
In message , Brian Gaff
writes
So Clive Sinclairs claim that a nuclear power station could run on a zx81 is
a little irrisponsible then.


The ZX81 was very reliable - provided you raised it a little by standing
it on a book, so that the RAM pack (plugged in at the back) dangled in
the air. One day, all nuclear power stations will be controlled this
way.
--
Ian

Richard Tobin September 28th 10 11:11 AM

Why do we have to keep rebooting things?
 
In article ,
Brian Gaff wrote:

So Clive Sinclairs claim that a nuclear power station could run on a zx81 is
a little irrisponsible then.


A lie perhaps, but not very irresponsible since no-one in a position
to use one for that purpose would actually believe him.

-- Richard

Richard Tobin September 28th 10 11:13 AM

Why do we have to keep rebooting things?
 
In article ,
Ian Jackson wrote:

The ZX81 was very reliable - provided you raised it a little by standing
it on a book, so that the RAM pack (plugged in at the back) dangled in
the air. One day, all nuclear power stations will be controlled this
way.


Unfortunately by then physical books will be a rare commodity. Does
it work if you stand it on a Kindle instead?

-- Richard

Richard Tobin September 28th 10 11:18 AM

Why do we have to keep rebooting things?
 
In article ,
Brian Gaff wrote:

Of course there is always the multiple computer approach as used in aviation
where several systems work together and the moment one of these disagrees
its voted off and rebooted.


Almost all the errors that cause your gadgets to reboot - and probably
most of the ones that cause planes to crash - are software errors, so
as well as several computers you need several independently-written
programs that do the same task, otherwise they will all get it wrong
together.

-- Richard

Ivan[_2_] September 28th 10 11:33 AM

Why do we have to keep rebooting things?
 

" wrote in message
...
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot? Couldn't satellite receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the same
channel of course?).



Why don't they just admit defeat and stick a reset button on the remote
control (IIRC didn't Nokia or have something similar back in the Ondigital
days?) a least it would save grovelling around on one's knees trying to
unplug the mains.


Ivan[_2_] September 28th 10 12:37 PM

Why do we have to keep rebooting things?
 

"brightside S9" wrote in message
...
On Tue, 28 Sep 2010 10:33:38 +0100, "Ivan"
wrote:


" wrote in message
...
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot? Couldn't satellite receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the same
channel of course?).



Why don't they just admit defeat and stick a reset button on the remote
control (IIRC didn't Nokia or have something similar back in the Ondigital
days?) a least it would save grovelling around on one's knees trying to
unplug the mains.


Buy a radio controlled 13 amp plug cum socket. Though the remote
control can have undocumented feature(s).


Ten to one the remotely controlled 13 amp plug/socket would crash and
without doubt in the 'off' condition!





Richard Russell September 28th 10 12:38 PM

Why do we have to keep rebooting things?
 
On 28 Sep, 09:28, bugbear wrote:
They put a lot of effort into making the EMS boot up nearly
instantaneously, and rebooted it (from a simple timer)
every couple of seconds!


Many years ago I designed a 'beacon keyer' for unattended operation at
a transmitter site; I really didn't want it to require a manual
reboot! So I connected the *reset* pin of the CPU (a Z80) to the
output of a divider off the master clock, which caused it to be reset
*tens of times per second*. Another possible source of instability is
corrupted RAM, so it had none: the only read/write storage in the
whole machine was the Z80's registers (around 48 bytes in all) -
fortunately they don't get cleared by a reset. It only once required
attention in several years of operation, when the crystal oscillator
failed.

Richard.
http://www.rtrussell.co.uk/


Gary September 28th 10 01:00 PM

Why do we have to keep rebooting things?
 

"Ivan" wrote in message
...

"brightside S9" wrote in message
...
On Tue, 28 Sep 2010 10:33:38 +0100, "Ivan"
wrote:


" wrote in message
...
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot? Couldn't satellite receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the same
channel of course?).



Why don't they just admit defeat and stick a reset button on the remote
control (IIRC didn't Nokia or have something similar back in the
Ondigital
days?) a least it would save grovelling around on one's knees trying to
unplug the mains.


Buy a radio controlled 13 amp plug cum socket. Though the remote
control can have undocumented feature(s).


Ten to one the remotely controlled 13 amp plug/socket would crash and
without doubt in the 'off' condition!






I worked for a manufacturer of a CNC mill set up.
They had a Emergency Stop that used the software .

I thought that was silly, no one listened.

A customer had a fault one day and the tool started going through the mill
table. They hit the Stop and nothing it kept on milling.

Then they found the main switch and turned it off, lost the programme,
everything off.

They then had to retrofit a simple power Emergency stop an all past and
future production.

Much safer.

Gary


AnthonyL September 28th 10 01:19 PM

Why do we have to keep rebooting things?
 
On Mon, 27 Sep 2010 17:51:51 -0700 (PDT), "
wrote:

Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot?


I switch everything off every night. I never have to reboot. ;)


--
AnthonyL

tim.... September 28th 10 01:24 PM

Why do we have to keep rebooting things?
 

"Java Jive" wrote in message
...
Would you want your PVR to reboot in the middle of recording?


One of mine randomly decides that it wants to do as "disk check" during
which it is capable of doing nothing else, and at least once this was in the
middle of a recording. What's the difference?



Alan White[_2_] September 28th 10 02:30 PM

Why do we have to keep rebooting things?
 
On Tue, 28 Sep 2010 09:18:05 +0000 (UTC),
(Richard Tobin) wrote:

Almost all the errors that cause your gadgets to reboot - and probably
most of the ones that cause planes to crash - are software errors, so
as well as several computers you need several independently-written
programs that do the same task, otherwise they will all get it wrong
together.


I think that Boeing use three different, independently written programs
for the three flight computers whereas Airbus use the same software in
each.

--
Alan White
Mozilla Firefox and Forte Agent.
Twenty-eight miles NW of Glasgow, overlooking Lochs Long and Goil in Argyll, Scotland.
Webcam and weather:-
http://windycroft.co.uk/weather

Dickie mint September 28th 10 02:33 PM

Why do we have to keep rebooting things?
 
On 28/09/2010 11:21, brightside S9 wrote:

Buy a radio controlled 13 amp plug cum socket. Though the remote
control can have undocumented feature(s).


In the initial BBC DTT stage 1998 - 2009?, when the Coding & mux went
through the Regions we fitted a simple telephone operated switch to the
Monitoring control PC. Despite some very stable software written in
house (BNCS), Windows would manage to crash occasionally.

Believe it or not, cutting edge technology C & M and all, if we couldn't
"see" the regional installation remotely we'd dial up the switch and
send the "off" code. Hang up, wait a couple of minutes, dial up again
and send "on" code. Now that's a elaborate PDR (Power Down Reset) !


Richard

John Legon September 28th 10 08:53 PM

Why do we have to keep rebooting things?
 
At 03:38:40 Tue, 28 Sep 2010, Richard Russell
wrote:

Another possible source of instability is
corrupted RAM, so it had none: the only read/write storage in the
whole machine was the Z80's registers (around 48 bytes in all)


48 bytes! I can only remember 24:

a - f a' - f' IX i
b - c b' - c' IY r
d - e d' - e' SP
h - l h' - l'

How do you get the other 24?

--
John L

Steve Thackery[_2_] September 28th 10 11:34 PM

Why do we have to keep rebooting things?
 
Some really good answers.

I would summarise it very simply: cost, and time-to-market.

While ever we - the buying public - reward companies who get their
widget to market first, or sell it the cheapest, we'll be stuck with
crash-prone products.

It is perfectly possible to make highly resilient, fault-tolerant
systems which will struggle on even in the face of hardware failures or
software glitches.

These are usually found where the device has a lot riding on it and
can't be repaired economically (e.g. a space probe); where the
consequences of failure are unacceptably high (e.g. flight control
systems); where the scale of the failure would be very large (e.g.
telecommunication systems), and so forth.

All sorts of self-testing and remote testing strategies can be
implemented, as well as layered recovery strategies, and so forth.

But yer average £100 domestic box just doesn't cut it, I'm afraid.
They are merely designed to work. In case that sounds odd (and just
what you want), I mean no attention is given to handling situations
where some (or any) part of the system stops working. In almost all
cases we see some undefined behaviour (usually a "freeze"). Undefined,
because no attention was given to it during the design phase.

Not the kind of thing you want to happen with your nuclear cancer
treatment machine!

SteveT



[email protected] September 29th 10 01:05 AM

Why do we have to keep rebooting things?
 
I think you have collectively answered my question. In summary, the
reason things crash is because they are built to a price.

Bill


Graham. September 29th 10 01:12 AM

Why do we have to keep rebooting things?
 


"Roderick Stewart" wrote in message
.myzen.co.uk...
In article de898962-6535-4431-9faa-
,
wrote:
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot? Couldn't satellite receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the same
channel of course?).


It would need software to detect the problem and make the decision to do
this - but it's usually software that is the cause of the problem in the
first place. Catch 22.

There's no substitute for a brain, and a finger on a button.

Or a big hammer.

Or a mechanical time-clock to interupt the supply for a few minuets at around 4am

--
Graham.

%Profound_observation%



Graham. September 29th 10 01:16 AM

Why do we have to keep rebooting things?
 


"Richard Tobin" wrote in message ...
In article ,
Ian Jackson wrote:

The ZX81 was very reliable - provided you raised it a little by standing
it on a book, so that the RAM pack (plugged in at the back) dangled in
the air. One day, all nuclear power stations will be controlled this
way.


Unfortunately by then physical books will be a rare commodity. Does
it work if you stand it on a Kindle instead?


Will posh schoolgirls balance Kindles on their heads?
Just a thought.

--
Graham.

%Profound_observation%



[email protected] September 29th 10 01:46 AM

Why do we have to keep rebooting things?
 
On Tue, 28 Sep 2010 13:30:46 +0100, Alan
wrote:

I think that Boeing use three different, independently written programs
for the three flight computers whereas Airbus use the same software in
each.


Boeing use common code and hardware in their CCS, it was one of the
reasons for the 787s delay, convincing the authorities that the code
was 'bug-free'

Airbus have always used seperate teams programming different hardware
running two different programming languages on their five flight
computers (3 primary, 2 secondary)

David Paste[_2_] September 29th 10 01:57 AM

Why do we have to keep rebooting things?
 
On 28 Sep, 01:51, "
wrote:
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot? Couldn't satellite receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the same
channel of course?).

Bill


Even your own feet need rebooting from time-to-time
(yerseewaddadidthere?!)

Well, to philosowaffle a little bit, I think that other than the
reason you have stated elsewhere, building to a price, there is
another reason. People assume that anything can be designed /
engineered / build to be 'perfect'. However, this is based in the
general consumer's dreams. Consider the law of unintended consequences
and how nature deals with it's systems. Nothing in nature is designed
to run perfectly (nothing is designed, full stop), rather, actions are
simply reactions to a very basic set of stimulus. Walking is simply
stopping yourself falling over in quick succession, as a crude
example. We, long ago, developed a method of locomotion that used 4
limbs, and the limbs and spine developed accordingly. Something,
somewhere went right or wrong, and homo sapiens now walk on 2 limbs.
And get bad backs. And fall over more than we really need to. As
bipeds, we are simply alpha-release candidates.

Also: feature bloat.

I feel that I had something more to say, but really, it's a bit late
for me to carry on coherently. I hope I have managed to get this far
OK.

Things need to be tended to for as long as they are alive /
operational. That's the crux of it. Good design can reduce this burden
but not remove it. Also, good design usually means eliminating
superfluous features / the weak / the sick / the vulnerable, etc etc.
One species - one niche. One machine - one job.


Alan White[_2_] September 29th 10 09:07 AM

Why do we have to keep rebooting things?
 
On Wed, 29 Sep 2010 00:46:51 +0100, "
wrote:

Boeing use common code and hardware in their CCS, it was one of the
reasons for the 787s delay, convincing the authorities that the code
was 'bug-free'

Airbus have always used seperate teams programming different hardware
running two different programming languages on their five flight
computers (3 primary, 2 secondary)


Thanks for that. I've updated my brain.

--
Alan White
Mozilla Firefox and Forte Agent.
Twenty-eight miles NW of Glasgow, overlooking Lochs Long and Goil in Argyll, Scotland.
Webcam and weather:- http://windycroft.co.uk/weather

Ian Jackson[_2_] September 29th 10 09:16 AM

Why do we have to keep rebooting things?
 
In message , Graham.
writes


"Richard Tobin" wrote in message
...
In article ,
Ian Jackson wrote:

The ZX81 was very reliable - provided you raised it a little by standing
it on a book, so that the RAM pack (plugged in at the back) dangled in
the air. One day, all nuclear power stations will be controlled this
way.


Unfortunately by then physical books will be a rare commodity. Does
it work if you stand it on a Kindle instead?


Will posh schoolgirls balance Kindles on their heads?
Just a thought.

And how far can they walk if the power lead is connected?
--
Ian

Richard Russell September 29th 10 11:39 AM

Why do we have to keep rebooting things?
 
On 28 Sep, 19:53, John Legon wrote:
48 bytes! *I can only remember 24:

* * * * a - f * * *a' - f' * * *IX * * *i
* * * * b - c * * *b' - c' * * *IY * * *r
* * * * d - e * * *d' - e' * * *SP
* * * * h - l * * *h' - l'

How do you get the other 24?


I can't count! Anyway, it was enough for that particular application.

Richard.
http://www.rtrussell.co.uk/

Mark[_13_] September 29th 10 05:26 PM

Why do we have to keep rebooting things?
 
On Tue, 28 Sep 2010 10:33:38 +0100, "Ivan"
wrote:


" wrote in message
...
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot? Couldn't satellite receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the same
channel of course?).



Why don't they just admit defeat and stick a reset button on the remote
control


Because if the device has frozen it won't be responding to the remote
at all.

I'd have thought it would be fairly straightforward to implement a
watchdog feature in a mass produced device.

--
(\__/) M.
(='.'=) Due to the amount of spam posted via googlegroups and
(")_(") their inaction to the problem. I am blocking some articles
posted from there. If you wish your postings to be seen by
everyone you will need use a different method of posting.


Steve Terry[_2_] September 29th 10 05:39 PM

Why do we have to keep rebooting things?
 
"Mark" wrote in message
...
On Tue, 28 Sep 2010 10:33:38 +0100, "Ivan"
wrote:
" wrote in message
...
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot? Couldn't satellite receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the same
channel of course?).


Why don't they just admit defeat and stick a reset button on the remote
control


Because if the device has frozen it won't be responding to the remote
at all.


Yes but you can buy a mains power saver that disconnects power to
peripheral units if the device on the main socket has been switched by
remote control to standby.
So put the crashing PVR / Freesat / Freeview box, etc on the
peripheral power socket and say the TV on the main socket, then
when you use the TV remote to switch the TV off and on, it'll also
switch power off and on to the buggy peripherals.

Steve Terry
--
"I would like to plead for my right to investigate natural phenomena
without having guns pointed at me.
I also ask for the right to be wrong without being hanged for it."
- Wilhelm Reich, November 1947



Steve Thackery[_2_] September 29th 10 08:20 PM

Why do we have to keep rebooting things?
 
wrote:

In summary, the
reason things crash is because they are built to a price.


And to a very short timescale.

SteveT



Jim Lesurf[_2_] September 30th 10 10:01 AM

Why do we have to keep rebooting things?
 
In article
,
wrote:
I think you have collectively answered my question. In summary, the
reason things crash is because they are built to a price.


In the standard model of the 'Western Market Economy' items are made to be
*sold*, not to be *used*. And almost no-one does any in-depth or long term
assessment of problems like rebooting due to crashes. By then, the next
'model' is on sale. As per the churning in markets like computing and
consumer electronics in general.

Witness also the shabby designs (in terms of *useability*) of so many brown
goods, despite often being functionally the same as items made for many
decades. Yet new models often re-commit past errors, or are worse than the
same maker's earlier examples. Often, the only think they want to learn
from previous models is what *sold* best. Not what works best. Or they use
a different design team who are clueless about previous achievements or
failures.

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics
http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html


PeeGee September 30th 10 10:25 AM

Why do we have to keep rebooting things?
 
On 29/09/10 16:39, Steve Terry wrote:
wrote in message
...
On Tue, 28 Sep 2010 10:33:38 +0100,
wrote:
m wrote in message
...
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot? Couldn't satellite receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the same
channel of course?).

Why don't they just admit defeat and stick a reset button on the remote
control


Because if the device has frozen it won't be responding to the remote
at all.


Yes but you can buy a mains power saver that disconnects power to
peripheral units if the device on the main socket has been switched by
remote control to standby.
So put the crashing PVR / Freesat / Freeview box, etc on the
peripheral power socket and say the TV on the main socket, then
when you use the TV remote to switch the TV off and on, it'll also
switch power off and on to the buggy peripherals.

Steve Terry


Doesn't that tend to negate the usefulness of a PVR :-)

--
PeeGee

"Nothing should be able to load itself onto a computer without the
knowledge or consent of the computer user. Software should also be able
to be removed from a computer easily."
Peter Cullen, Microsoft Chief Privacy Strategist (Computing 18 Aug 05)

Mark[_13_] September 30th 10 10:39 AM

Why do we have to keep rebooting things?
 
On Wed, 29 Sep 2010 16:39:33 +0100, "Steve Terry"
wrote:

"Mark" wrote in message
.. .
On Tue, 28 Sep 2010 10:33:38 +0100, "Ivan"
wrote:
" wrote in message
...
Everything from satellite receivers to computers seems to need
unplugging from the mains so often and plugging back in. How come? Why
don't they make these things so that when they're incapable of doing
their job they just automatically reboot? Couldn't satellite receivers
(for instance) just run some sort of self-check routine in the
background and if it fails do a reboot? (and come back on the same
channel of course?).

Why don't they just admit defeat and stick a reset button on the remote
control


Because if the device has frozen it won't be responding to the remote
at all.


Yes but you can buy a mains power saver that disconnects power to
peripheral units if the device on the main socket has been switched by
remote control to standby.
So put the crashing PVR / Freesat / Freeview box, etc on the
peripheral power socket and say the TV on the main socket, then
when you use the TV remote to switch the TV off and on, it'll also
switch power off and on to the buggy peripherals.


Unfortunately this would not be very useful if the device was a PVR.
--
(\__/) M.
(='.'=) Due to the amount of spam posted via googlegroups and
(")_(") their inaction to the problem. I am blocking some articles
posted from there. If you wish your postings to be seen by
everyone you will need use a different method of posting.


David Paste[_2_] September 30th 10 04:07 PM

Why do we have to keep rebooting things?
 
On 30 Sep, 09:01, Jim Lesurf wrote:

Witness also the shabby designs (in terms of *useability*) of so many brown
goods, despite often being functionally the same as items made for many
decades. Yet new models often re-commit past errors,


But by then, we've changed our behaviour to deal with these errors...

or are worse than the same maker's earlier examples.


....and they are familiar to us, so there is an inertia against /
better/ product(s).

Cheers.


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