microcontroller with usb host port?

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Hello everybody,

I'd like to display pictures from a webcam on a small display.
The cheapest webcams are USB; so I'd like to use a microcontroller to
get the images off and send them to a display.

I've already found several ic's with usb slave functionalities; but
are there any with a host port?

I've already read about the zaurus 6000; but with several hundred
it's a bit expensive.

I'd prefer 8051 or compatible, but I'm willing to learn other
microcontrollers as well.


Thank you for your help!


Regards,

Phil

Re: microcontroller with usb host port?
: Hello everybody,

: I'd like to display pictures from a webcam on a small display.
: The cheapest webcams are USB; so I'd like to use a microcontroller to
: get the images off and send them to a display.

: I've already found several ic's with usb slave functionalities; but
: are there any with a host port?

: I've already read about the zaurus 6000; but with several hundred ?
: it's a bit expensive.

: I'd prefer 8051 or compatible, but I'm willing to learn other
: microcontrollers as well.


Every USB host controller needs a controll stack. It will be quite a big
deal to program  that stack...
--
Uwe Bonnes                 snipped-for-privacy@elektron.ikp.physik.tu-darmstadt.de

Institut fuer Kernphysik  Schlossgartenstrasse 9  64289 Darmstadt
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Re: microcontroller with usb host port?

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I looked at a few 8051 parts with USB, and the impression I got was
that they simply could not be a master, no matter how much effort
one is willing to put into programming them.

I would like to develop a product that can get input from a
USB keyboard (being fast enough to handle a USB mouse would
be icing on the cake) using a low-cost 8-bit uC (8051, Z80,
or 6502 preferred but I can work with anything).  I am willing
to put in a lot of effort developing firmware if it gets my
unit cost down. Does anyone have any suggestions for an
appropriate device?

--
Guy Macon <http://www.guymacon.com
 


Re: microcontroller with usb host port?

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As I've stated here before, my personal impression of USB is that its
inventor went out of its way to make sure it was nearly impossible to
use with anything less than a full-blown PC as the host.  I.e. USB is,
at its very heart, not so much a data link but a clever plot to make
sure Intel can continue to sell PC processors 'til kingdom come.

No standard 8051 will suffice to replace that PC designed into the
very heart of USB.  A very high-end derivative (e.g. the DS80C400,
a.k.a. TINI) might have the horsepower, but even then, the cost of
developing all the necessary layers of software would be prohibitive.

Bottom line: you don't want to develop your own USB host protocol
stack.  If you do it nevertheless, you'll need more horsepower than
your average 8-bitter to do it.


--
Hans-Bernhard Broeker ( snipped-for-privacy@physik.rwth-aachen.de)
Even if all the snow were burnt, ashes would remain.

Re: microcontroller with usb host port?

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Bear in mind that many USB keyboards and mice will also speak PS/2 as they are
supplied with simple
adaptors which are just pin converters.

Re: microcontroller with usb host port?
On Mon, 22 Nov 2004 15:23:28 +0000, Guy Macon
<http://www.guymacon.com wrote:

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If all you want to interface to is a keyboard (or lowspeed devices),
you may be able to do it bit banging the usb interface. Some guy
claims to have done it:
http://www.cesko.host.sk/IgorPlugUSB/IgorPlug-USB%20 (AVR)_eng.htm


The OP wants a full speed device, much more a problem. I don't know if
an 8051 could keep up with the data from a camera, much less handle a
usb host interface too.

The Ubicom Ip2k can do USB host, but a LOT of software would need to
be done to manage misc devices. And you would still be in device
driver hell where Vendor's buggy usb device problems get worked around
by a windows driver.

I looked at doing a reverse FDTI system with a Ubicom IP2k ie. serial
to USB host. The problem is that it is a lot of work and without
serious volume the price would be high.

Regards, Steve
 


Re: microcontroller with usb host port?

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Here the combination of the ATmega128 and the AT43USB380 might work.
You may need to have a Hub as well. (AT43301) to interface to several units

There is a USB client as well on the AT43USB380.


--
Best Regards
Ulf at atmel dot com
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Re: microcontroller with usb host port?
in comp.arch.embedded:

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The only shipping microcontroller that I know of with a USB host
controller built-in is Atmel's AT91RM9200, a 180MHz ARM 9 part.  It
has 16KB RAM and no flash on-chip.  The host controller is USB 1.1,
not 2.0.

The USB protocol was deliberately designed to be very uneven.  By that
I mean that most of the hardware and software is on the host side, as
little as possible on the peripheral device side.  This is so that
small peripheral devices like mice could be as inexpensive as
possible.

The result of this is that in addition to the host controller device,
whether it is built into the micro or not, you need complex USB host
driver software.  The Atmel part above can run Linux, but I do not
know if there is a Linux driver for it's USB host controller.

--
Jack Klein
Home: http://JK-Technology.Com
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Re: microcontroller with usb host port?


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Do you think that it might be feasable to make a "man in the middle"
system that goes between a USB keyboard and a PC?  I am currently
developing a device that does that for the purpose of adding features
needed by the handicapped (sticky keys, fumble keys, etc.), and will
probably throw in an optional Dvorak conversion just because I can.
My design assumes a standard PS/2 keyboard.  I have never done any
work with USB; does it lend itself to a system that does simple
modifications to the data stream without having its own host protocol
stack?

http://www.xpcgear.com/usbtops2gn.html *appears* to have an adapter
that will act as a USB host, but I rather suspect that somehow the
keyboard stops acting like a USB device and starts acting like a
PS/2 device...








Re: microcontroller with usb host port?

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Feasible: proably, but hardly worth the bother.  Essentially all
operating systems worth worrying about that will run on the PC of your
"man in the middle" already have pure software solutions for such
stuff.  I.e. why bother trying to do a man in the middle in hardware,
when XP already has the necessary functionality?

--
Hans-Bernhard Broeker ( snipped-for-privacy@physik.rwth-aachen.de)
Even if all the snow were burnt, ashes would remain.

Re: microcontroller with usb host port?

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Because many blind people are using DOS. Because someone using a
mouth stick may wish to change the BIOS settings on his PC. Because
an NT system may have two users, one of whom uses a Dvorak keyboard
and both of whom want to login using the keymapping they like.
Because it is a royal pain in the ass to install many operating
systems using a Dvorak keyboard.  Because *someone* is keeping
DvortyBoard (Dvorak keyboard that looks like a Qwerty to the PC)
in business.  Because OS-X doesn't do the keymapping for Japanese
keyboards correctly.  Because some corporations lock down Windows
in such a way that it is impossible to change the keymapping. Because
Knoppix Dvorak users get tired of changing the keyboard in Qwerty at
every boot.

  


Re: microcontroller with usb host port?

snipped-for-privacy@4ax.com...
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EZ-Host chip from Cypress is another cheaper but less powerful alternative.

Friendly yours,

--
Robert Lacoste
ALCIOM - The mixed signal experts
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Re: microcontroller with usb host port?
On 22 Nov, in article

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Have you thought about the code and data set sizes. Most webcam devices
prefer their data to be sent then sent tio display, and you may have to
keep a full image ready to transfer to the display. Most webcams are QVGA
(Quarter VGA) resolution of 320 x 240 giving 75KB of data storage before
you start doing anything else with it. Worst still you may have to buffer
more than one images worth if the webcam sends the data as a compressed
image file format.

The code and data space for USB hosting is NOT trivial, especially with
all the enumerators and device handling cases you will need for all the
possible supported cameras. Especially as the webcams are going to be
replaced with new models every two months at the SLOWEST rate.

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I don't think most 8051 derivatives have easy memory handling of this
sort of data sizes and the potential code sizes required.
You may find one with a fast enough clock, but I feel this is better
suited to a cheap 16/32 bit cpu.

--
Paul Carpenter          | snipped-for-privacy@pcserviceselectronics.co.uk
<http://www.pcserviceselectronics.co.uk/ PC Services
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Re: microcontroller with usb host port?
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there any with a host port?
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bit expensive.

AT91RM9200 running Linux will do what you want. May even be a driver for USB
cameras...

Atmel has an Embedded USB Host, the AT43USB380.
This will run the USB host stack on the chip, and the USB profile will run
on a low end micro.
The part has a programmable 8/16/32 bit peripheral interface
so it can interface to lowly 8 bitter.
The API for the host stack is Atmel proprietary, and only the API to the
profiles are released.
Unfortunately, I do not think that Video is supported at this time.
Since the library is delivered in binary form, then you also need a
supported architecture.
Today this means AVR or ARM. Supported profiles today are HID, Mass Storage
and Printer.
Serial might be around soon.

If you use a typical Webcam, then realize that a VGA picture is 307,200
pixels.
You need to be able to address a significant amount of RAM to store that
and it is a little tough on an 8 bitter.

The Mass Storage code will fit into about 64 KB on an AVR.

You might be better of getting a camera module and interface to an FPGA
also containing the LCD display.  AT91K40 FPSLIC?



--
Best Regards
Ulf at atmel dot com
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Re: microcontroller with usb host port?
snipped-for-privacy@marek.priv.at (p.marek) wrote :

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hmm SoCs :
broadcom BCM 4702/4712/BCM4704P for example, but its an evil company


Pozdrawiam.
--
RusH   //
 http://randki.o2.pl/profil.php?id_r35%2019
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Re: microcontroller with usb host port?

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Cypress Semiconductor CY7C67300 (EZ-Host), CY7C67200 (EZ-OTG),
Apparently Arrow don't have stock, but their price is US$8.25 ea

Re: microcontroller with usb host port?

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http://www.cypress.com/cfuploads/img/products/cy7c67300.pdf

Looks good.  Supports low speed and full speed, but not high speed.
Then again, nothing reasonable that you hook to iy can keep a
high speed USB pipe full...



Re: microcontroller with usb host port?
Hi Phil!
I'm also into 8051 based USB controllers. I suggest you to go for
AT89C5131 USB controller from ATMEL.
If interested to have further conversation, plz let me know.
thanks & regards,
vasu
(Srinivasa Reddy Muly)


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