Embedded Internet

Do you have a question? Post it now! No Registration Necessary

Translate This Thread From English to

Threaded View
Greetings All!

 I'm a final year EE engineering student working with
microcontrollers. As part of my course i'm supposed to design and
implement an embedded sys. I thought of controlling some application
through the internet. While i have some know how of the software
required, i've absolutely no idea *what* application to control. My
profs expect me to design somethin that needs an RTOS and
multitasking.

Can anyone *suggest* an application that needs this? Also, i've a
serious allergy to mechanics and moving parts. Any amount of
electrical hardware i can handle.

Thanks in Advance,
Devyn

Re: Embedded Internet

Quoted text here. Click to load it

    How about a home environmental control system?  This is a project in
progress, the top table of links aren't fleshed out yet but the bottom
group do work on the embedded 8051.

    http://www.amresearch.com:2005 and
    http://www.amresearch.com:2005/test.html

    Other Embedded Ethernet projects might be:

- Security System
- Landscape Controller
- Solar water heater
- Off-line refrigeration for environmental control
- Home defense system
- Entertainment system

    And a _lot_ more.  I don't see the utility in putting a refrigerator
online but someone has already done that but when targeted applications
can be put online for cheap your imagination is the limit.

-- Regards, Albert
----------------------------------------------------------------------
AM Research, Inc.                  The Embedded Systems Experts
http://www.amresearch.com 916.780.7623
----------------------------------------------------------------------


Re: Embedded Internet
Albert Lee Mitchell said...
Quoted text here. Click to load it

Can't help but to notice the good responses he's getting by
being upfront about this being school-related as opposed to the
the ones posting poorly-disguised homework questions.

Quoted text here. Click to load it

How about an on-line refrigerator with an optical beer-counter
inside?  With a web-enabled cellphone you could easily decide
the correct amount to purchase while standing in the grocery
store.

 
Casey

Re: Embedded Internet


Quoted text here. Click to load it

Big difference between asking for ideas vs what's_the_answer eh?

Quoted text here. Click to load it

Awesome suggestion! I hope he posts the website so I can buy one when
complete.

Regards,
Ray



Re: Embedded Internet


Quoted text here. Click to load it
...


This is because he is not asking someone to design it for him.
He is just asking for a good application.
Key to succeeding is here to limit the size of the application.
Most people I talk to that want to do Telematics are looking for 2 MB of
Flash.
I'd hate to write 2 MB of code for  a students project.


--
Best Regards,
Ulf Samuelsson   ulf@a-t-m-e-l.com
We've slightly trimmed the long signature. Click to see the full one.
Re: Embedded Internet
Ulf Samuelsson said...
Quoted text here. Click to load it

True, which makes it interesting to discuss and play around
with.

Quoted text here. Click to load it

Me too.  It would be even worse if all of it had to work.



Casey

Re: Embedded Internet

Quoted text here. Click to load it
able to
the
multitasking.
key
another
station
and
up on
fancy, you
and
queries to
download
then the
this
standby
the

Why not utilise GPRS and have the controller send the info via email, ftp,
etc by itself to some server on the internet.



Re: Embedded Internet
Quoted text here. Click to load it



How about a device that will let me program my VCR from work: Display a web
page displaying the 'remote' buttons. Button presses send an IR signal to
the VCR. After each button press, display a captured screen of the vcr video
output.

For extra credit, have it answer the phone, and on receipt of a DTMF
password, power up the computer/router for the poor suckers who are still on
dialup [they will need ethernet + dial-on demand + dyndns].

Re: Embedded Internet
WARM Greetings Everyone!

 Thank you very much for the fantastic suggestions. While it will take
me some time to think about all the responses, I'm sure any one will
serve the purpose more than well. I guess students of my generation
are lucky that we have the internet and all the good people answering
questions.

Once again thank you all.

So far I've designed a control system that uses a weighing machine (in
a rather crude way; i didnt design it myself, just ripped its' output)
to keep track of the components in a storage shed. Assuming all the
components weigh the same, it should be easy to calculate the no. of
components leaving the shed. So once the weighing machine registers
the weight, the microcontroller sends an email (through a PC; dont
have time or know-how to design a TCP/IP stack) stating the no. of
components that left the shed. Well, rather unimpressive, considering
its an open loop control system and not very useful. I have to
physically place 30 pins or whatever on the scale to get the system
going. Moreover the prof wants a better RTOS. I still have about 2
months to finish it. I'll work on the replies.

Regards,
Devyn

Re: Embedded Internet

Quoted text here. Click to load it

station
Quoted text here. Click to load it

Hi,

The first time I'v heard about this kind of application,
it was 6 years ago (1998) : the purpose of this system
was to keep a close eye on a river and prevent
inundations. The system was powered by a solar panel
and NiCd cells. At this time, it use to work
whit a GSM-Data phone (GPRS didn't exist).
So, this project, if not really original, is
a good (and usefull) embedded project.

You should keep in mind that "embedded" doesn't mean
it must be "self-powered" nor "handled" : It can be a
realtime system, like a thermal regulation for a house...

a weather station is not realtime time at all :
even a PC running Win95 can do it !

Regards
Emmanuel

Re: Embedded Internet
You may consider Hitachi processors. Very powerfull devices, and lot of
tools.

An example at:

http://www.stacktools.com/page/cdir.c?dir=ucmodules/ST2011

Cheers,

Gerard Zagema



Re: Embedded Internet
Marko said...
Quoted text here. Click to load it

Sorry, but that's one of the most uninformative web sites I've
seen in some time.   Might want to finish it some of it first
before giving the URL out.


Casey



Re: Embedded Internet
Quoted text here. Click to load it

Yet another person learns how to hang a Realtek
ethernet chip on a cheap processor and port
a open-source stack to it...


Re: Embedded Internet

Quoted text here. Click to load it

    Well, to give him credit, at least he accomplished something.  That was
an invaluable lesson, if he understood the source code.  I'm sure his next
version will have significant improvements.

    My problem with the Realtek parts is that they require most/all of the
pins available on an embedded microcontroller and mos/all of the cpu
resources.  This is why we went with the WC3100 and Cygnal, most of the
i/o and cpu is still available for applications.  Just serving webpages
doesn't do us much good unless the 'server' can do something of value like
turn a lamp or toaster on/off at least.
 
-- Regards, Albert
----------------------------------------------------------------------
AM Research, Inc.                  The Embedded Systems Experts
http://www.amresearch.com 916.780.7623
----------------------------------------------------------------------


Re: Embedded Internet

Quoted text here. Click to load it

Well, you can memory map the Realtek so it will cost you one additional line
(CS). You also can use the READYIO and connect it to the wait pin (another
line). It's possible to use the DTC (data transfer controller) to retrieve
the data from the RealTek in background.



All the other pin's and ports are for the fun of the user so you can
switch/control more then you probably ever need for an embedded project like
this. The modules like ST2011 are used quite a lot now for ModBUS interfaces
and GUI's for PLC's. You don't need any more pins then the RS485.



But we have also user who use this device for monitoring temperature and
controlling Fan's for potatoes conservation. They use four of the 8 ADC's
inputs and two outputs for relais.



Regards,



Gerard Zagema



Re: Embedded Internet

Quoted text here. Click to load it

    Of course you can but not at the cost of a single pin.  To interface
directly with a Realtek, not just the PHY chip, requires address and data
pins which eat all the h/w resources of a microcontroller.  If no h/w
resources remain why bother?  Nobody needs a webserver that's not
extensible.  For instance how would you interface a LCD and keypad after
all the I/O has been eaten in the Realtek interface?

Quoted text here. Click to load it

    I disagree.  Bill Gates once asked, "Why would anyone want more than 640k
of RAM?"  History proves that users will quickly swallow every feature and
ask for more.

Quoted text here. Click to load it

    That's a great start.  Do you have the CPU resources to do a Fuzzy
Inference between web requests or to do an interpolation of non-linear
data?  When your hardware _and_ software are maxed out it severely limits
the possiblities.  I prefer to design for the future, not the past.

-- Regards, Albert
----------------------------------------------------------------------
AM Research, Inc.                  The Embedded Systems Experts
http://www.amresearch.com 916.780.7623
----------------------------------------------------------------------


Re: Embedded Internet

Quoted text here. Click to load it

I think Gerard was referring to designs which already interface to an
external memory bus. In those circumstances, the CS line could well be
externally decoded, along with all else, in a PAL or whatever. That's
the benefit of memory mapping everything - zero overhead.

But even using a true microcontroller, the overhead of the RTL8019AS
isn't all that great, since you don't actually need most of the
address lines, and they can just be pulled. An example is Microchip's
POC board for 10-baseT, which uses only five address lines, or 15 I/Os
in total - reasonable on a 40-pin chip with 33 I/Os:
http://www.microchip.com/download/tools/picmicro/demo/pdemnet/39563b.pdf

Quoted text here. Click to load it

They aren't. Many pins on complex chips aren't really essential to
basic operation, and good embedded designers learn to cut out the dead
wood.

Quoted text here. Click to load it

You're never required to deliver real working systems today, then?
Nice job.

--
  Max

Re: Embedded Internet

Quoted text here. Click to load it

    Maybe it depends on what the definition of "is" is.  15 i/o pins on a
microcontroller eats quite a bit of cpu resources when most of those pins
have to be bit-banged plus a lot of embedded micros require quite a few of
those I/O pins when external memory is needed which would eliminate its
use for an embedded controller/server.

Quoted text here. Click to load it

    Sarcasm is not a good way to have dialog, smartass.
 
-- Regards, Albert
----------------------------------------------------------------------
AM Research, Inc.                  The Embedded Systems Experts
http://www.amresearch.com 916.780.7623
----------------------------------------------------------------------


Re: Embedded Internet

Quoted text here. Click to load it

Sorry, that's just not true. The demo board I mentioned is quite
capable of running a simple web server with only a cheap PIC16F877
@5MIPS, doing HTTP, TCP, UDP, ICMP, IP, ARP etc. in addition to
driving the Realtek chip. If you need more horsepower for your APP,
swap it for a PIC18 @10MIPS, or re-design with whatever MPU you fancy.

Quoted text here. Click to load it

If external memory is being used, then you'd presumably memory-map the
PHY, as Gerard suggested, which results in zero overhead on I/O pins
(or one pin for CE if you're not externally decoding address spaces).

Quoted text here. Click to load it

Well, what sort of response do you expect to that sort of meaningless
pomposity? I fail to see what is wrong with hanging a Realtek PHY on a
cheap MCU to achieve 10-baseT connectivity, given that it meets the
requirements of the project in hand. You seem to be suggesting that
all projects should be over-engineered to allow for some nebulous
degree of future expansion, irrespective of whether the client
requires it or not (and, presumably, irrespective of cost). Frankly, I
think that's an untenable position to take.

--
  Max

Re: Embedded Internet
Quoted text here. Click to load it

Well, StackTos is not an open project but it is our own OS. It is working
now for several years in some hostile environments.

But I know, it's always easier to criticize then to give some constructive
information.

To hang an Ethernet controller on a cheap processor that is what this
discussion is about, if I'm right, so I don't understand the
insinuations....or is it a compliment? In that case......Thanks.

Gerard Zagema






Site Timeline