Not getting speed USB2 speed with my Hewlett Packard Photosmart 8450printer?

On 5/27/2007 12:33 PM PT, Dan G wrote:

>> How much faster is the memory card reader directly to the PC via USB?
>> How about those internal drive ones that I see in some brand computers
>> in stores?
>
> I have a little USB SD card reader here that will upload raw 5MP images as
> fast as I can open them in Photoshop.
>
> The main difference is that your PC has processor and memory power that a
> printer lacks, so the reading process is sped up. You should also get a new
> card, as the newer ones are much faster. But you don't really need to go to
> the expense of getting a "high speed" card unless you are pro using a pro
> camera that benefits from the speed. Any of the current crop of 1GB cards
> are a great value.

Yeah, I don't take a lot of photographs but I do notice if I have many
photograph files to put on PC, it can be a long wait.


> A previous poster stated that there are 2 types of USB2, which is false.
> There's only USB1.1 and USB2.

Ah.
--
"The evaluator counts the ants at the picnic of progress." --Mohan Singh
/\___/\
/ /\ /\ \ Phillip (Ant) @ http://antfarm.ma.cx (Personal Web Site)
| |o o| | Ant's Quality Foraged Links (AQFL): http://aqfl.net
\ _ / Remove ANT from e-mail address: philpi@earthlink.netANT
( ) or ANTant@zimage.com
Ant is currently not listening to any songs on his home computer.

Dan G wrote:
> "Ant" <ANTant@zimage.com> wrote in message
> news:4659d7b7$0$16588$4c368faf@roadrunner.com...
>> How much faster is the memory card reader directly to the PC via USB?
>> How about those internal drive ones that I see in some brand computers
>> in stores?
>
>
> I have a little USB SD card reader here that will upload raw 5MP images as
> fast as I can open them in Photoshop.
>
> The main difference is that your PC has processor and memory power that a
> printer lacks, so the reading process is sped up. You should also get a new
> card, as the newer ones are much faster. But you don't really need to go to
> the expense of getting a "high speed" card unless you are pro using a pro
> camera that benefits from the speed. Any of the current crop of 1GB cards
> are a great value.
>
> A previous poster stated that there are 2 types of USB2, which is false.
> There's only USB1.1 and USB2.
>
Really?? How do you explain the vast differences among USB2 speeds?

--
john mcwilliams

"John McWilliams" <jpmcw@comcast.net> wrote in message
news:8OydnXLIlZLKaMTbnZ2dnUVZ_gOdnZ2d@comcast.com. ..
> Really?? How do you explain the vast differences among USB2 speeds?
>


I don't have to. USB2 is an interface, it has no "speed". It does have a
rated limit of around 480 MB/sec BURST RATE, which is virtually meaningless,
as burst rates only occur, (you guessed it), in bursts. There are many
things that affect USB2 TRANSFER RATE speeds, but as a rule it tops out
around 20-25 MB/sec under ideal circumstances. The most common limitation
for sustained transfer speeds on a PC using USB2 is the USB controller in
the PC. Many controllers are, frankly, crap. The 2nd most common limitation
is the device itself that is connected, as these also have chipsets that
control the USB2 and can affect speeds. #3 is the type of transfer, i.e.
write vs. read. Write is always slower than read on USB. This is due to the
overhead involved with writing.

Bottom line is that even on a bad day, the worst USB2 controller can match
the speeds from any standard memory card.

"Dan G" <none@12345.org> wrote in message
news:PtSdndtmpMw_QcTbnZ2dnUVZ_o-knZ2d@comcast.com...

> A previous poster stated that there are 2 types of USB2, which is false.
> There's only USB1.1 and USB2.

Not quite. USB2 has several variants. Low Speed and Full Speed USB 2.0 are
really just the backward compatible variant of USB 1.1, but they are still
USB 2.0. Hi Speed USB 2.0 is the fast one, 480Mb/s. There are different
USB 2.0 logo's for the various modes, see
http://www.usb.org/developers/packaging/.

There has been a bit of historical revision about what USB 2 really means,
since the original definition (as given above) meant that any USB 1.1 device
pretty much became a form of USB 2.0 device. Later guidelines have
attempted to clear up some of the confusion (and disgust) of consumers by
calling them USB and Hi-Speed USB and mostly dropping the confusing and
misleading USB 2 designation.

Regards,
Bob Headrick, MS MVP Printing/Imaging

Dan G wrote:
> "John McWilliams" <jpmcw@comcast.net> wrote in message
> news:8OydnXLIlZLKaMTbnZ2dnUVZ_gOdnZ2d@comcast.com. ..
>> Really?? How do you explain the vast differences among USB2 speeds?
>>
>
>
> I don't have to. USB2 is an interface, it has no "speed". It does have a
> rated limit of around 480 MB/sec BURST RATE, which is virtually meaningless,
> as burst rates only occur, (you guessed it), in bursts. There are many
> things that affect USB2 TRANSFER RATE speeds, but as a rule it tops out
> around 20-25 MB/sec under ideal circumstances. The most common limitation
> for sustained transfer speeds on a PC using USB2 is the USB controller in
> the PC. Many controllers are, frankly, crap. The 2nd most common limitation
> is the device itself that is connected, as these also have chipsets that
> control the USB2 and can affect speeds. #3 is the type of transfer, i.e.
> write vs. read. Write is always slower than read on USB. This is due to the
> overhead involved with writing.
>
> Bottom line is that even on a bad day, the worst USB2 controller can match
> the speeds from any standard memory card.

I didn't need more reasons to convince me that USB sucks, period. That's
why I recommend firewire readers.

But do read Mr. Headrick's post. In addition, there are moderate, slow,
and painfully slow USB transfers, and if it's the chipset in the card
reader, so be it.

--
john mcwilliams

On Sun, 27 May 2007 15:49:32 -0600, Dan G wrote:

>> Really?? How do you explain the vast differences among USB2 speeds?
>
> I don't have to. USB2 is an interface, it has no "speed". It does have a
> rated limit of around 480 MB/sec BURST RATE, which is virtually
> meaningless, as burst rates only occur, (you guessed it), in bursts. There
> are many things that affect USB2 TRANSFER RATE speeds, but as a
> rule it tops out around 20-25 MB/sec under ideal circumstances.

Sorry, but that's incorrect. There are two versions of USB 1 and
two versions of USB 2. USB 1 supports speeds of 1.5Mb/sec and
12Mb/sec. The former is generally used by USB mice and keyboards.
USB 2's two versions are USB 2.0 Full Speed (12Mb/sec) and USB 2.0
High Speed (480Mb/sec). Many of the first devices (such as cameras)
that were advertised as having USB 2.0 ports used the more limited
Full Speed version, and they were *slow*.

Note, btw, that it's 480Mb/sec, not 480MB/sec. The fastest card
reader I've seen tested is Sandisk's Extreme IV. With the fastest
card (not surprisingly, Sandisk's Extreme IV CF card) it has managed
not burst, but sustained read rates of 40MB/sec, which is only
slightly slower (whether overhead is or isn't taken into account)
than 480Mb/sec.


> Bottom line is that even on a bad day, the worst USB2 controller
> can match the speeds from any standard memory card.

I can agree with that if you qualify it as "the worst USB2 High
Speed controller". If you connect a fast USB2 card reader to a
USB2.0 Full Speed port (max. 12Mb/sec) only the slowest 1x cards
(150kb/sec, or 9Mb/sec) can be transferred as fast as the card's
potential allows. Almost all cards sold today range from 20x to
150x, and as a fairly rough rule of thumb, a ##x speed card using a
USB 2.0 High Speed port can transfer files ##x time faster than if a
USB 2.0 Full Speed port is used.

If you want to check this, here's a clip from a message that was
posted last year. I just checked both of the URLs contained in it
and they're still valid, and both are worth reading :

> From: "Joel Kolstad" <JKolstad71HatesSpam@yahoo.com>
> Newsgroups: alt.music.mp3.hardware
> Subject: Re: Full speed USB 2.0
> Date: Fri, 15 Sep 2006 09:25:21 -0700
> Message-ID: <12glkvhn06c3g65@corp.supernews.com>
>
> . . .
>
>> well, before doing that,,,here's a link
>> http://www.everythingusb.com/usb2/faq.htm
>
> What they're saying there is that the USB 2.0 *specification* supports
> 480Mbps. That does *not* imply that all devices that are USB 2.0 complaint
> *must IMPLEMENT all features of the USB 2.0 specification*. (It's just like
> RS-232 serial ports and modems... just because your PC has a serial port
> that's 115.2kbps, and a modem says it's compatible with that serial port,
> there is no implication that the modem itself will make use of the 115.2bps
> transfer rate available.)
>
> Here's more information that clarifies all this:
> http://www.crucial.com/library/understanding_usb.asp
>
> Although, as I already mentioned, I do think some 90+% of people who label
> something as "full speed USB 2.0" do so in an attempt to make people *think*
> it's a high-speed device. The faster we can educate people that this isn't
> the case, the better.

Here's a newish comparison of some current SD cards:

http://www.pcper.com/article.php?aid=407

The gist of it is that actual measured read and write speeds are vastly
slower than the "rated speeds", and that using a direct USB card reader
seems to be the fastest route.

Dan G wrote:
> say
>>> you're stuck with that speed. Printers never use the capability of USB2
>>> either.

> That said, it's also true that the printer will also be slow in reading the
> card, slower than your PC will be. You'd be far better off to buy a little
> USB dongle for reading the card directly on your PC.

OTOH My HP C5180 _is_ using USB2.0 for card reading. Takes very short (2
minutes or so - definitely shorter than my old USB1 card reader) to
download almost full 512M card.
Don't understand though why scanner is so slow? Did they mismatched USBs
inside that printer? (faster went for reader and slower for scanner?)


--
Jerry1111