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'[EE:] USB cable length. Why we stretch it.'
2004\01\10@142808 by Robert Rolf

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Herbert Graf wrote:
{Quote hidden}

Didn't this particular thread start out as someone wanting to extend
USB cabling to way beyond the spec'd length?

If USB is NOT meant to be extended, then why the ready availability of
extension cables and repeaters and USB to fibre/ethernet links, etc. devices?
What is is MEANT for, and what people try to USE if for are of course two
divergent things.

I totally agree that putting a USB camera at the end of a 100' cable is
not in the spec, but when the camera only costs $50 (thanks to USB) people will
spend $100 trying to extend it, rather than pay $400 for an ethernet
camera which may not be compatible with their motion sensing software
anyway. I went down this path several years ago when we were trying to
come up with a very low cost way to put up bolid (bright meteors) cameras
into an observing network. A web camera with suitable sensitivity was
1/10th the cost of CCTV camera feeding coax to a digitizing card, but the
USB cabling just couldn't handle the distance to the roof (120' or so).
The result was a lot fewer observing stations for the same budget.
Journal of The Royal Astronomical Society of Canada, Dec 2003 has an
article on this camera network. It is not available on line.

People are also using web cameras on telescopes (spam_OUTQCUIAGTakeThisOuTspamyahoogroups.com)
so again, they -want- cabling longer than specs allow (remotely controlled
goto scopes).

So Herbert, I long ago 'GOT IT', but people like me will still -try- to
bend the specs to make it work because of it's low cost.
That doesn't change the fact that I hate the poor quality of USB drivers
and the way they stack up in a Winblows box.

Robert

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2004\01\10@152036 by Josh Koffman

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Robert Rolf wrote:
> If USB is NOT meant to be extended, then why the ready availability of
> extension cables and repeaters and USB to fibre/ethernet links, etc. devices?

Well, I of course can't speak for everyone, but I can tell you why I use
extensions. I know they break the spec. However, I have a number of
software programs that use USB dongles as hardware keys. As well, I have
a 4 USB based flash drives. None of my computers has a USB port on their
front panel, and reaching around back is extremely hard. So, I have a
USB extension on each computer coming around to the front of the box. It
allows me to swap away with ease.

Admittedly, I should be using USB hubs to do this.

As an aside, I have a feeling that a lot of your negative experience was
caused by Win98. I know, it says USB works on Win98, but in my
experience it's flakey at best. I've had much better luck with Win2K,
and the few times I've used XP it seems to be ok as well. I'm about to
upgrade my last Win98 machine to Win2K, and this is one of the main
reasons.

Josh
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2004\01\10@155909 by Herbert Graf

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> >         Which is what USB was NOT meant for, I don't know why
> you STILL don't get
> > that. For most users a webcam WILL be near to PC, for the
> others there is
> > ethernet, which is more expensive, or other means (such as WiFi which is
> > even more expensive).
>
> Didn't this particular thread start out as someone wanting to extend
> USB cabling to way beyond the spec'd length?

       Yes, and they were told what the consequenses were.

> If USB is NOT meant to be extended, then why the ready availability of
> extension cables and repeaters and USB to fibre/ethernet links,
> etc. devices?
> What is is MEANT for, and what people try to USE if for are of course two
> divergent things.

       That is irrelevant. You're saying just because a car is MEANT to drive on a
road doesn't mean I have to keep it there. People will always try to stretch
what things are meant for (look at email), they do so at their own peril.
However this has no bearing on the technology and what the spec is.

> I totally agree that putting a USB camera at the end of a 100' cable is
> not in the spec, but when the camera only costs $50 (thanks to
> USB)

       So, because USB made it possible to lower the cost of certain items, and
because people are trying to use these items out of spec, means it's USB's
fault???? You're saying getting things for less is a BAD thing? I think you
are now simply confused as to what you are complaining about.

> people will
> spend $100 trying to extend it, rather than pay $400 for an ethernet
> camera which may not be compatible with their motion sensing software
> anyway.

       And what is wrong with that, if it works you've saved a good amount of
money, why is that bad?

> I went down this path several years ago when we were trying to
> come up with a very low cost way to put up bolid (bright meteors) cameras
> into an observing network. A web camera with suitable sensitivity was
> 1/10th the cost of CCTV camera feeding coax to a digitizing card, but the
> USB cabling just couldn't handle the distance to the roof (120' or so).
> The result was a lot fewer observing stations for the same budget.
> Journal of The Royal Astronomical Society of Canada, Dec 2003 has an
> article on this camera network. It is not available on line.

       Ok, so let me get this straight, you were trying to do something OUT OF
SPEC, and you blame the spec??? Listen, if you want to do something out of
spec there is NOTHING stopping you, but blaming the technology is simply
ridiculous.

> People are also using web cameras on telescopes (.....QCUIAGKILLspamspam.....yahoogroups.com)
> so again, they -want- cabling longer than specs allow (remotely controlled
> goto scopes).

       And your POINT?

> So Herbert, I long ago 'GOT IT', but people like me will still -try- to
> bend the specs to make it work because of it's low cost.
> That doesn't change the fact that I hate the poor quality of USB drivers
> and the way they stack up in a Winblows box.

       The fact people are trying to do things out of spec and the fact that you
don't "like" USB are two completely separate issues and have no relation to
each other. So what exactly is your point?

       USB, when used for what it was meant for, works VERY well. If people try to
do things USB was never meant for they have NO RIGHT to complain.

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2004\01\10@164340 by Robert Rolf

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Herbert Graf wrote:
Mike Singer wrote:
> > Who are you to forecast future?
>
>         Not the future. Look at today: what percentage of users of webcams want
> them more then say 10 meters from their PC?

What percentage of webcams would be put more than 10 meters from the PC
if the spec easily allowed for it? LOTS. The availability of repeaters
proves that there is a demand for this, notwithstanding the spec.
Surely the spec writers could have anticipated this? Of course not.

>         So, because USB made it possible to lower the cost of certain items, and

No, the mass production of products lowered the cost. Having turn-key USB
chips/software stacks, etc. made it easier to get into the marketplace.
Having big, well funded players push the technology also helped.

On the other hand, we have all three items for Bluetooth, yet where is it?

> because people are trying to use these items out of spec, means it's USB's
> fault???? You're saying getting things for less is a BAD thing? I think you
> are now simply confused as to what you are complaining about.

No. I simply acknowledged the validity of many of the points you've made,
AND complained about the problem of having to load so many different drivers BECAUSE
of the USB spec. I don't have a problem with different drivers for different
classes of device, but I DO expect that the spec would require all of a particular
class to use a 'standard' driver. e.g. Storage devices, mouse device, etc.

>         Ok, so let me get this straight, you were trying to do something OUT OF
> SPEC, and you blame the spec??? Listen, if you want to do something out of

I didn't blame the spec. I gave the example to explain why people TRY to go
beyond spec.

> spec there is NOTHING stopping you, but blaming the technology is simply
> ridiculous.

I did nothing of the sort. I know that there are intrinsic limitations to
all specs. What I object to is the silliness of having to load a different
driver for nearly every USB device. I have 4 different web cams on my security
box. I had to load 4 DIFFERENT drivers to get them to work.  Why did the
USB spec not just define a 'standard' protocol for cameras, like the ATA spec
for hard drives? Or SCSI, or SATA or...?  It is this lack of common drivers
that I am bitching about. But that's the "USB way" so I'll shut up now.

>         USB, when used for what it was meant for, works VERY well. If people try to
> do things USB was never meant for they have NO RIGHT to complain.

So how exactly, is my ATTEMPT to use USB MP3 players 'not what USB was meant for'?
If they looked like a storage device, then they would work without any 'extra'
drivers, wouldn't they? But they don't.

The fact remains that USB MP3 players require unique drivers for EACH device,
rather than using a common 'storage class' driver. This is just plain stupid, RIAA
notwithstanding. The 'custom' device driver does nothing to improve the customer
experience, and -this- customer has been really turned off by the experience.

Thanks for the critique Herbert.

Robert

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2004\01\10@164801 by Wouter van Ooijen

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> Surely the spec writers could have anticipated this? Of course not.

everything has its price. had the spec taken 50 m into account the
result would have been more expensive, slower, or both, and USB might
have failed to take off. if you think you are good at directing a
specification process I suggest you grow pointy hair :)

Wouter van Ooijen

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2004\01\10@170843 by Herbert Graf

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> On the other hand, we have all three items for Bluetooth, yet where is it?

       Bluetooth is a technology that was simply over hyped. When people finally
figured out what Bluetooth was they were disappointed by all the
limitations, resulting in VERY slow acceptance. I still don't own a SINGLE
device that has Bluetooth, and I don't expect to own one any time soon.

       Personally Bluetooth was simply out of place, it wasn't define tight enough
for the masses to understand, and as a result few devices have it.

{Quote hidden}

       Again, don't blame the spec. The spec HAS defined "standard" devices, the
MANUFACTURERS decided to "go it on their own", and USB allows them to (can't
blame USB for that, leaving things open for devices outside of "predefined"
types was pretty much required). Again, it's not USB's fault that you had to
load all those drivers, put the blame where it belongs.

> >         USB, when used for what it was meant for, works VERY
> well. If people try to
> > do things USB was never meant for they have NO RIGHT to complain.
>
> So how exactly, is my ATTEMPT to use USB MP3 players 'not what
> USB was meant for'?

       The manufacturers require a custom driver and didn't conform to the mass
storage spec. The manufacturers made this choice based on the threat of
attack from the RIAA if they didn't. So, blame the RIAA, I do. They (or
their equivalent in other countries) are the reason I pay a "tax" for every
piece of blank media I buy, even though I'm not using it to store copyright
material (mostly pictures I've taken, backups of my servers, etc.). Of
course in the case of my country it pretty much makes downloading
copyrighted music "legal", so I guess there is some benefit.

> If they looked like a storage device, then they would work
> without any 'extra'
> drivers, wouldn't they? But they don't.

       Again, not USB's fault, put the blame where it belongs.

> The fact remains that USB MP3 players require unique drivers for
> EACH device,
> rather than using a common 'storage class' driver. This is just
> plain stupid, RIAA
> notwithstanding. The 'custom' device driver does nothing to
> improve the customer
> experience, and -this- customer has been really turned off by the
> experience.

       See above.

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2004\01\10@171052 by Robert Rolf

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Wouter van Ooijen wrote:
>
> > Surely the spec writers could have anticipated this? Of course not.
>
> everything has its price. had the spec taken 50 m into account the
> result would have been more expensive, slower, or both, and USB might
> have failed to take off. if you think you are good at directing a
> specification process I suggest you grow pointy hair :)

Given that I have just fallen victim to an arbitrary spec'ing process
I wish I could grow pointy hair.

BTW I was not being sarcastic this time. It really IS impossible
to anticipate everything in a spec. Just ask NASA, who bent it's
own rules, and lost two shuttles as a direct result.

R

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2004\01\10@174208 by Robert Rolf

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Herbert Graf wrote:

> > of the USB spec. I don't have a problem with different drivers
> > for different
> > classes of device, but I DO expect that the spec would require
> > all of a particular
> > class to use a 'standard' driver. e.g. Storage devices, mouse device, etc.
>
>         Again, don't blame the spec. The spec HAS defined "standard" devices, the
> MANUFACTURERS decided to "go it on their own", and USB allows them to (can't

OK Herbert, I agree with you. The problem is Manufactures who 'go their own way'
rather than trying to use an existing, well defined protocol that could work
for them. Must be their compulsive need to "own" intellectual property.

> blame USB for that, leaving things open for devices outside of "predefined"
> types was pretty much required). Again, it's not USB's fault that you had to

Of course.

> load all those drivers, put the blame where it belongs.

OK, you've convinced me. The spec is good. The makers are bad for
not using it well.

> > So how exactly, is my ATTEMPT to use USB MP3 players 'not what
> > USB was meant for'?
>
>         The manufacturers require a custom driver and didn't conform to the mass

No, they CHOSE to use a custom driver. The device does nothing more than
decode/encode files that are stored on it.

It may also have to do with licensing FATxx from Microsloth.
I tried one player that used SM cards. Couldn't see the card when
I wrote the file directly to the card. Had to 'format' the card in the unit, and
then shove the file out via their USB program. Of course the card wasn't readable
elsewhere. What a PITA.

> storage spec. The manufacturers made this choice based on the threat of
> attack from the RIAA if they didn't. So, blame the RIAA, I do. They (or

How pathetic. So instead of a one step process and choices on how I
interact with the copy process, I have a two/three step.
But it sure cut down on piracy didn't it? (yet another long thread <G>).

> their equivalent in other countries) are the reason I pay a "tax" for every
> piece of blank media I buy, even though I'm not using it to store copyright
> material (mostly pictures I've taken, backups of my servers, etc.). Of

I have exactly the SAME complaint. And they just raised the rates while
they're sitting on $61 million that was supposed to go to the ripped
off Canadian artists. Who the heck is pirating Canadian artists? The big
ones are all signed up with American distributors.

> course in the case of my country it pretty much makes downloading
> copyrighted music "legal", so I guess there is some benefit.

Here it's now legal to clone CD's for 'personal use'. Transcoding
to MP3 is technically illegal because strictly speaking, it's no
longer a 'copy' even if it sounds nearly the same. But you are also
allowed to make a 'backup' copy of your media, so who knows.

> ----------------------------------
> Herbert's PIC Stuff:
> http://repatch.dyndns.org:8383/pic_stuff/

So why doesn't your logic analyser use a USB interface instead of that
'legacy' parallel port?? ;}

R

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2004\01\10@190750 by Herbert Graf

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> Herbert Graf wrote:
> > > So how exactly, is my ATTEMPT to use USB MP3 players 'not what
> > > USB was meant for'?
> >
> >         The manufacturers require a custom driver and didn't
> conform to the mass
>
> No, they CHOSE to use a custom driver. The device does nothing more than
> decode/encode files that are stored on it.

       Agreed, when I said "require" I meant they require the user to use a custom
driver for their device.

> It may also have to do with licensing FATxx from Microsloth.

       I'm not convinced Microsoft CAN patent FAT. It's been public domain for so
long I don't think their claims would stand up in court. I guess we'll have
to wait and see.

> I tried one player that used SM cards. Couldn't see the card when
> I wrote the file directly to the card. Had to 'format' the card
> in the unit, and
> then shove the file out via their USB program. Of course the card
> wasn't readable
> elsewhere. What a PITA.

       Haven't encountered such a situation. Was it an mp3 player?

{Quote hidden}

       Yup. Every time someone asks where the money has gone the "group"
responsible for it says, in essence, the cheque is in the mail. Amazing what
kind of corruption is out there.

> > course in the case of my country it pretty much makes downloading
> > copyrighted music "legal", so I guess there is some benefit.
>
> Here it's now legal to clone CD's for 'personal use'. Transcoding
> to MP3 is technically illegal because strictly speaking, it's no
> longer a 'copy' even if it sounds nearly the same. But you are also
> allowed to make a 'backup' copy of your media, so who knows.

       It puts the whole downloading music issue into a grey area, I don't think
prosecution would work here for downloading copyrighted music, but we won't
know until someone tries it.

> > ----------------------------------
> > Herbert's PIC Stuff:
> > http://repatch.dyndns.org:8383/pic_stuff/
>
> So why doesn't your logic analyser use a USB interface instead of that
> 'legacy' parallel port?? ;}
>
> R

       Actually it uses a serial port. The reason it uses a serial port is it was
designed at a time when my machine didn't have USB, and I didn't run an OS
that supported USB. If I were to design it today I would most definitely use
a USB-serial chip. TTYL

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2004\01\12@081543 by o-8859-1?Q?Tony_K=FCbek?=
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Hi,

<removed discussions regarding USB, cable length and the apparent uselessness of Bluetooth>

Well there is an quite neat marriage of these technologies available,
you can get this:
http://www.blu2i.com/products/info.asp?id=1

An 200kps 200 m range USB->bluetooth->serial i/f
;)

and that for about $60 at each end ...

ofcource 200kps might not be realtime video quality, but it sure is decent
enough for still image transfer even at high resolution.

food for thought...

/Tony

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2004\01\12@164825 by Andrew Warren

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Robert Rolf <RemoveMEPICLISTspamTakeThisOuTmitvma.mit.edu> wrote:

> What I object to is the silliness of having to load a different
> driver for nearly every USB device. I have 4 different web cams on
> my security box. I had to load 4 DIFFERENT drivers to get them to
> work.  Why did the USB spec not just define a 'standard' protocol
> for cameras, like the ATA spec for hard drives?

   There IS a video class-driver spec; it's downloadable from:

       http://www.usb.org/developers/devclass_docs

> It is this lack of common drivers that I am bitching about. But
> that's the "USB way" so I'll shut up now.

   There's no lack of common drivers; if you look at the web page I
   referenced above, you'll see Human-Interface Device, Mass
   Storage, Video, Still Image, Audio, Smart Card, Communications,
   Printers, etc.

   The "USB way" is to use those drivers; manufacturers who choose
   to use their own non-standard drivers are, I think,
   short-sighted.

> If [MP3 players] looked like a storage device, then they would
> work without any 'extra' drivers, wouldn't they? But they don't.

   Sure they do.

> The fact remains that USB MP3 players require unique drivers for
> EACH device, rather than using a common 'storage class' driver.

   Most MP3 players (and many cameras, and all compact-flash
   cards) DO look like mass-storage devices, so they DO interface
   without additional drivers to any modern Mac, PC, or Linux
   machine.

> This is just plain stupid, RIAA notwithstanding. The 'custom'
> device driver does nothing to improve the customer experience, and
> -this- customer has been really turned off by the experience.

   The RIAA isn't the reason for custom drivers.  Some player
   manufacturers don't want to implement complex flash
   file-management protocols within their players; instead, they do
   all the difficult work with a custom driver on the PC side.
   Others include custom drivers so their players can be used with
   Windows 98, which doesn't include its own mass-storage class
   driver.

   No one WANTS to write a custom USB driver; everyone prefers to
   talk to a standard class driver if one's available.  I don't
   know why all your MP3 players wanted to load custom drivers, but
   if you're using an OS newer than Win98, you should easily be
   able to find a player that works with the built-in mass-storage
   driver.

   -Andy

=== Andrew Warren -- aiwEraseMEspam.....cypress.com
=== Principal Design Engineer
=== Cypress Semiconductor Corporation
===
=== Opinions expressed above do not
=== necessarily represent those of
=== Cypress Semiconductor Corporation

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