What does 'embedded' really mean?

The computer is part of a system, not standalone.

Rene

Well, you didn't say "embedded processor" so I assume you just can't f Main Entry: em·bed Variant(s): also im·bed /im-'bed/ Function: verb Inflected Form(s): em·bed·ded also im·bed·ded; em·bed·ding also im·bed·ding transitive verb

1 a : to enclose closely in or as if in a matrix b : to make something an integral part of c : to prepare (a microscopy specimen) for sectioning by infiltrating with and enclosing in a supporting substance 2 : to surround closely intransitive verb : to become embedded

IMOH this isn't too far off from what we mean when we say "embedded processor" or "embedded (computer) system".

I take the term "embedded processor" to mean any processor that's embedded into a system, the purpose of which is _not_ to present my processor in a pleasing aspect -- so while the Pentium that is helping me write this is in some sense embedded in the PC, it's not really embedded.

On the other hand, the MSP430 that's controlling the little levitating dingle-ball by my elbow* _is_ embedded, even though I can see through the clear plastic of the evaluation kit from TI to the processor.

Rather than finish the article (or book) that one could start this way, I'm just going to point out that I've seen a number of articles already written, most of which are probably available online with some digging.

• It's for a seminar I'm to be giving. I wanted a demo that was easy to build, cool to look at, and presented a challenging control problem. An inverted pendulum apparatus would look better from across a room (the dingle ball is only a 5/8" diameter), but would require more time in the metal shop. Controlling the temperature at the end of a bar of aluminum could certainly present some interesting challenges if you tried to do it fast, but it wouldn't offer much eye candy -- so I'm levitating a dingle ball.

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Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Posting from Google?  See http://cfaj.freeshell.org/google/

"Applied Control Theory for Embedded Systems" came out in April.
See details at http://www.wescottdesign.com/actfes/actfes.html

In article , Mike Noone writes

An embedded system is a computer no one buys. It's is a computer system that is an integral part of something else.

Any good?

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\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
\/\/\/\/\ Chris Hills  Staffs  England     /\/\/\/\/
/\/\/ chris@phaedsys.org      www.phaedsys.org \/\/\
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Scroll thru this:

*-embedded-*-is-*-computer-system-that+*-*-user-doesn't-think-of-as-*-computer+not-modified-*-often+zz-zz+*-logic-is-programmed-into-*-hardware+or-at-all+*-opposite-of-*-*-a-general-purpose-computer-system

In my opinion, the most important feature defining an embedded computer (digital system) as opposed to a general-purpose computer is the specific function the embedded computer is supposed to provide. As a corollary, the user interface of an embedded system is very simple (allowing only configuration, not development), or even non existing, as in completely automatic systems.

Worth mentioning, the size is not important. I wouldn't consider a PDA, although small size (compared to desktop / laptop computers), being an embedded computer. It's just nowadays stage of technology when we can afford such miniaturisation. I can imagine in the near future a microsystem attached to my goggles that I can speak to in C language and develop software applications onto and this will still be a general-purpose computer.

Regards, Adrian

'emb'' from the greek 'ember' meaning 'hot little thing'..

'ed' the original designer

'ded' what happened to ed when his design overheated.

geez I thought everyone knew that.

Best yet, Chris.

Hul

Chris Hills wrote:

I like it, except that it addresses itself to an "embedded system" but not directly to the single word, 'embedded,' itself and as an adjective that might also be applied to software as in "embedded software" or "embedded development" and so on. But I think you are right on track.

Let me provide a short example out of something I read in a book called "Plain Talk," written back in the late 1940's (I think.)

Question: "How do you tell the difference between a wholesale egg and a retail egg?"

Answer: "A retail egg is bought by someone who buys it to eat it."

So perhaps the meaning as an adjective is just that embedded things are actually meant to be _embedded_ as a fixed part of something. For example, in the case of embedded software it means that the software is intended as a fixture in the device -- that it should not actually be removed by the end user. In the case of embedded software development, it means the development of such embedded software. Etc.

Jon

There's not really a need to define it, you just have to read it closely: its a contraction of "has been put in a bed". Before being used in the sense that names this newsgroup, it meant that an object is embedded in something else: fossils are embedded in rock, a tree can embed a lamp post by growing around it, and so on.

So: an embedded system is a system that's hidden inside some other system so completely that doesn't appear on the outside. A quick-n-dirty test would be: how many separate programs can that computer run? If the answers is any of "Huh, what computer?", "Zero", "One" or "Two", it's an embedded computer system.

I'm convinced there is no concrete definition. Like all terms outside the realm of pure mathematics and philosophy (and possibly some of the more hard-core corners of theoretical physics), i.e. all words used by real people working on practical problems, its meaning is quite vague

--- and that's what makes it useful. Computing isn't divided into embedded and non-embedded any more strictly than the world is divided into black and white.

What about the chips in DVD players or digital TV set-top boxes? Both of these can run a certain amount of externally-supplied software, such as interactive facilities or even simple games, but I'm sure most would consider these to be embedded applications.

I'm sure there are other examples out there as well.

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Andrew Smallshaw
andrews@sdf.lonestar.org

So far, so good.

This is true for many embedded systems, but not all. Arguably embedded systems developed with VxWorks, for example, provide significant debugging facilities.

Agreed.

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          Michael Kesti            |  "And like, one and one don't make
                                   |   two, one and one make one."
    mrkesti at hotmail dot com     |          - The Who, Bargain