which out of these two cables/ports is best for my miniDV camcorder?

"Ilya Zakharevich" wrote in message
...
[A complimentary Cc of this posting was sent to
Peter D
[email protected]], who wrote in article :
If you know WHY the throughput is not close to the theoretical maximum,
please explain.

It's all there.

yeah, right...

It is. Your lack of comprehension doesn't make it any less so. Others have
explained it even better than I did. There's been a "plethora" or
non-technical and technical explanations. If you haven't "got it" yet, I
doubt you ever will. And that's too bad. But it's your problem, and not
mine. That said, here's one last attempt to sort through your whining.

The theoretical bandwith (400Mbit/sec) relies on perfect cable length,
perfect cable materials, and perfect hardware acting perfectly while
doing
nothing else.

If it were so, how would this differ from Firewire?

Huh? Firewire is better because it is more efficent, has lower CPU overhead,
and employs a more direct way of managing the data stream. USB doens't.

And since using
better cables and hardware which does nothing else DOES NOT improve
the USB throughput, I do not think this is a correct explanation.

Sure it does. But it doesn't improve it sufficiently to make it a viable
alternative to Firewire for Video transfer.

and more than one item on the USB 'network' degrades performance.

Why do you repeat this BS?

Because it's true.

Having a dedicated USB controller does not let performance to be anywhere
close to the theoretical maximum.

So? That's not what I said

further. USB is inherently "busy" and "chatty". And that makes it useless
for Vidoe transfer if Firewire is available.

Year, right! Now a presence of Firewire starts to influence USB
performance...

What? You really need to work on your English langiage comprehension skills!
There is no way to read those two sentences and come to the conclusion you
did.

Anyway, I'm done. The common language of communcation in this thread is
English. If it's not your first language and you're unwilling to improve
your comprehension skills, I can't help you any further. Good luck.

On Tue, 22 Jan 2008 21:47:53 +0000 (UTC), Ilya Zakharevich
wrote in :

[A complimentary Cc of this posting was sent to
Nomen Nescio
], who wrote in article :
Could you explain how latency is related to polling?

Could you explain how it's NOT?

Apparently, you never wrote any code which does polling without
latency...

True. Because it's not possible, even in a real-time OS, which Windows
is most definitely not. There is always some latency. The issue is how
much. The design of Windows makes it sometimes large enough to matter
in the case of USB.

Apparently (clearly) you've never written any Windows USB code.

The key is to know when data is available. This requires an adaptive
algorithm in setting up a wake-up timer, nothing more complicated.
After 5-6 cycles, you get the timer tuned-up, and run with minimal
overhead and no latency.

Hope this helps,

It doesn't, because like all simplistic answers, it doesn't work that
way in the real world.

I'm done with you on this thread too. Think what you want. I'm
guessing you're distantly related to Podge.

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

No wonder you use an anonymous remailer:

You're a complete asshole.

You're probably a Unitedstater,
lover of Bush and his gang of assassins and a
supporter of U.S. genocide throughout the world.

Yeah, if you sound like an asshole; you must be one.

Nomen Nescio wrote:
Ilya Zakharevich wrote:

The USB bus isn't interrupt-driven -- it's polled (as I wrote),
Do not see any significant difference. The poller would set up a
wake-up call, which would generate an interrupt. [And, BTW, why my
PCI hardware view shows that USB controllers use interrupts?]

Wow. You are one thick headed individual. Perhaps an analogy....

An Interrupt driven system would be like me using a baseball bat to get
your attention, and then telling you what to do.

A polled system would be like me wasting my time standing around
waiting for you to muddle through the jumble of "thoughts" in your head,
until you finally looked up with a blank stare on your face and asked
me what to do.

which is why latency can be an issue.
Could you explain how latency is related to polling?

Could you explain how it's NOT?

Sheesh!

[A complimentary Cc of this posting was sent to
John Navas
], who wrote in article :
Because you're so rude as to send email without a valid email return
address

What made you think so?

Puzzled,
Ilya

[A complimentary Cc of this posting was sent to
John Navas
], who wrote in article :
One more (last) time: USB is a simple cheap bus, very dumb

Sigh; all I asked for was a technical explanation, and all that the
posters provide is belles-lettres. [I explained what a *technical
explanation* of bus performance looks like in another message of this
thread.]

without the kind of priority interrupts and DMA transfers you're
assuming.

Sorry, I have no idea what you are taking about here. "Priority
interrupts" and "DMA transfer" are properties of the computer bus [one
"connected" to the motherboard], not of an "external" bus. So it
would be functions of *USB controller*, not of "USB bus", to have
these properties.

So, to enable high-speed transfers, a CONTROLLER should be able to
generate priority interrupts and DMA transfers. Do you say that there
are properties of USB *BUS* which do not allow controller to have
these interfaces ON THE MOTHERBOARD END?

DMA transfers still require cooperation. Somebody should set up the
buffers in time. (The difference, is, of course, in SIZE of the
buffer. So it is quantitative, not qualitative.)

Not true.

Could you be more specific, please? (Likewise for your other "it aint
so" replies...]

Thanks,
Ilya

On Wed, 23 Jan 2008 00:42:39 +0000 (UTC), Ilya Zakharevich
wrote in :

[A complimentary Cc of this posting was sent to
John Navas

The sucking sound you hear is my spam filter.
Got your post too unfortunately.

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

On Wed, 23 Jan 2008 00:31:25 +0000 (UTC), Ilya Zakharevich
wrote in :

[A complimentary Cc of this posting was sent to
John Navas
], who wrote in article :
Because you're so rude as to send email without a valid email return
address

What made you think so?



--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

[A complimentary Cc of this posting was sent to
John Navas
], who wrote in article :
Apparently, you never wrote any code which does polling without
latency...

True. Because it's not possible

I explained the algorithm.

even in a real-time OS, which Windows is most definitely not.

Why "Windows"? Did you just say that "on better OSes things are
better", or was it just "for good style"???

There is always some latency. The issue is how much.

Of course. And an adaptive algorithm would ensure that it is low enough.

Apparently (clearly) you've never written any Windows USB code.

Of course; I rarely SEE Windows...

Yours,
Ilya

[A complimentary Cc of this posting was sent to
John Navas
], who wrote in article :
On Wed, 23 Jan 2008 00:31:25 +0000 (UTC), Ilya Zakharevich
wrote in :

[A complimentary Cc of this posting was sent to
John Navas
], who wrote in article :
Because you're so rude as to send email without a valid email return
address

What made you think so?



Eh???!!! Should I repeat my question, or what?

Puzzled,
Ilya

On 1/22/08 4:06 PM, in article ,
"John Navas" wrote:

On Tue, 22 Jan 2008 21:42:49 +0000 (UTC), Ilya Zakharevich
wrote in :

[A complimentary Cc of this posting was sent to
John Navas ]

Because you're so rude as to send email without a valid email return
address, I've had to add you to the email spam filter.
Simply amazing that SO many people are wrong and YOU are the ONLY sane
person in here, isn't it, NavASS?