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Re: Req: (Free) Embedded Platforms for Education
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Yes. However there is a LOT of  source code that is available that is
not FOSS.   There are several very good OS that are free and the source
is available for non commercial use.

There is a lot of free software from silicon vendors that comes with no
license at all. Let alone the complex GPL.  So if students use the code
in something that becomes commercial they don't have to make it open
source.

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See above there is a LOT of source freely available that is not FOSS
The Micrium uCOS/II and FREE RTOS for example. There are others.


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It's not.


Certainly for 8 and 16 bit MCU

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At their cost. NOTHING is free in this life except programmers.



--
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
\/\/\/\/\ Chris Hills  Staffs  England     /\/\/\/\/
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Re: Req: (Free) Embedded Platforms for Education
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Only derived work is bound by the same license terms. If you build an
application using Linux as your OS you're free to do with that application
whatever you want. You have to provide source code for all the changes you
made to the OS itself, but then it's in your own best interest to have
those changes in mainline anyway.

Code that comes with no license at all basically means that you can't use it
at all. It has to be explicitly placed in the public domain, or you can't
do anything with it.
Source code from silicon vendors is often a horrible example as far as
licensing is concerned. What good is sample code that states in its header
that all rights are reserved, without a license telling me what I'm allowed
to do?
What makes this situation worse is example code for silicon vendor X's chip
written by compiler manufacturer Y, often with headers stating that you can
only use this code within Y's development environment.

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FreeRTOS is licensed under a modified GPL (using exceptions as defined in
GPL §7) to allow use of the FreeRTOS code in commercial applications
without having to open the code to the actual application that merely uses
FreeRTOS through the defined API. eCos comes with a similar GPL + exception
licenses since it was relicensed in 2002.

I couldn't find anything definitive on uc/OS-II licensing. The website says
that you should contact Micrium for licensing information, the source code
download is equally sparse on details.
The website further says that educational use doesn't require a license, but
I wouldn't know for sure what I'm allowed to do with it and what not.

You told us the GPL was complex?
... at least I'm allowed to read it.

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I was almost expecting that reply. Could we agree that lots of people
(except you) use networking gear that's running Linux, even if they
couldn't care less about FOSS?

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Heh, just another reason to avoid anything less than 32 bit ;)

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Well, of course someone has to write that software - but in most cases these
people benefit from the work others have done. Chances are they're using a
lot more free software they didn't write than what they're going to write
themself. Isn't software great? Once written everyone can use it, if you
give them right to do so... And if you're doing it right, noone's going to
take that code and run with it, making money from your work without giving
back.

Best Regards,

Dominic Rath

Re: Req: (Free) Embedded Platforms for Education



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Ask them. I am not being sarcastic. Not all software is or should be
in the public domain. There are companies like silicon companies
that invest a a lot in the development and support software of the
products  they sell. They are doing that because without some form
of return they cannot afford to invest in new technology of take
many of the risks on low return from products.  They don't want to
give their development costs away.


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The choice is obvious comply or don't use the code.

The real question is if I want to make a living developing innovative
software and the software is put in the public domain for free how
do I eat? Does it become a question of doing the innovation or
doing something else? If that is the case then development tools
are doomed to eventually all look like what GCC has become,
old technology.

The software technology we develop is for sale it is the only thing
that we do. Our customers share in the cost of this innovation by
spending a few man days equivalent for a copy of it. The companies
and individuals who determine that a copy of the new technology
will benefit them more than they pay for it are our customers.


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Call or email Jean Labrosse directly for licensing information on
licenses if you want to use uc/OS-II some something other than
educational use. Make a choice after you have all  the relevant
information you need.

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I am not sure what the last sentence means in the context
of the paragraph.

Walter..


Re: Req: (Free) Embedded Platforms for Education
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That was a direct reply to what Chris said about non-FOSS software that is
still free and could be used in a teaching context. They are of course free
to license their software in which way they want, but source code that
comes without any license telling me what to do or not is useless. Having
asked silicon vendors on both technical and legal matters I found it hard
enough to get answers to technical things, let alone on legal stuff. I
doubt it would be much of a problem to put a LICENSE[.txt if needed] into
the archive that tells me what they want me to do with that software and
what not.

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The problem is that a user who writes software for some product using
example code that is bound by these license terms is locked into using Y's
development environment. For a user who's aware of this problem, the
recommendation to look at non-FOSS code that's bound by such restrictions
isn't much of an option.

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Again, my point was just that including information on the licensing
somewhere easily accessible isn't asking too much.
An exceptionally good example is FreeRTOS. The "License and Warranty" page
clearly lists your options for licensing the software, and explains the
implications of these choices.
 
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The "it" that you could do "right" is "give them [the] right", i.e. the
licensing, and choosing which license to use. I was referring to the
difference between placing software in the public domain and using a free
software license that asks users of your code to give others the same
rights they were given.

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There's certainly a place for both free and proprietary software.
But I replied to someone who stated that FOSS wouldn't be the right choice
in the OP's teaching context - which in my opinion is just plain wrong. I
pointed out the shortcomings of some of the alternatives he offered, and
tried to show that his concerns about FOSS ain't that much of a problem in
the OP's context.

Regards,

Dominic

Re: Req: (Free) Embedded Platforms for Education



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The problem is that both the silicon companies and companies like
Micrium have negotiate licence agreements based on requirements
from both sides. Many silicon companies waive license fees for
their customers. What they don't want is to finance the development for
knock off competitors, licensing sets the bar a little higher for their
competitors and levels the competitive playing field.

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I stand by my comment. There may be many reasons that why code
is tied to specific tools. It is common for tools to utilize product
information that is not going to be publicly available. Silicon
technical marketing plans may very well be incorporated into tools
when they are developed. The code generation tools are responsible
for generating code for the silicon including dealing with the
underlying silicon issues. Silicon companies and parterning tool vendors
work together to support customers often making joint marketing
presentations and both participate in engineering reviews with
common customers.

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I followed the links on the page you referenced and eventually
reached the following in OpenRTOS section

" To obtain more information, discuss your individual support
  requirements, or enquire about purchase options and packages,
  please contact . . ."

Lots of licensing open questions in this document. That of course
is not your point that public licensing information is not that clear.

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The arguments that have been used for FOSS need to be critically
tested as well. Technically they don't come out that well, the
licence examples with the exception of GPL and one or two
others are a mess. Commercial licences are usually set up as
contracts between two entities.

FOSS does have problems in a teaching environment. The two most
serious problems are it often does not represent current best practices
and secondly it generally was not written with education in mind.

The tools that have been written specifically for education have done a
lot better job of educating students. Some examples over time have been
WATfor, UCSD pascal, XINU, most of Wirth's languages, Andy
Tanenbaum's offerings. The development of these products has
essentially ceased with the demand for zero cost no strings attached
tools especially for undergraduate fundamental education.  There is a
reason that schools that have continued to internally develop
educational tools in the area are sought after.



Regards

Walter Banks
--
Byte Craft Limited
 http://www.bytecraft.com
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Re: Req: (Free) Embedded Platforms for Education
On Fri, 20 Jul 2007 09:44:15 -0400, Walter Banks

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I have to say that "FOSS" remains a vague term for me.  It doesn't
carry exact and specific details in my mind.  It seems to me to simply
be a huge rug under which all manner of good and evil is swept.  So
anything I'll say here must take my own lack of precision on this term
into account.

The GPL is quite specific, in contrast to my muddled picture of FOSS
-- as you point out.

When you talk about "commercial licenses are usually set up as
contracts between two entities," what are you meaning to suggest,
here?  It's been my experience this is, by default, the well worn
legal ground of this kind of commercial business, generally.  So there
is no new information here, unless you intend it to be read in some
particular way I'm missing.  Could you elaborate about why you made
this comment in the context of both FOSS (which is vague) and GPL
(which is not?)

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"Best practices" is not a single, decisive point, though, Walter.  For
one thing, developing a thorough and well-worn (tested) curriculum
requires ages of serious effort.  It simply takes a lot of time to do,
and test.  Some folks even refine their testing, in some subjects such
as mathematics and reading, so that the __order__ of the questions is
itself tested for how it helps correlate positively.

We haven't yet heard back from the OP about many questions which
remain, but there is also a huge deciding difference here between the
case where they wish to simply teach to use as a library an existing
operating system, selecting one or more commercial systems for that,
and where they wish to actually teach to build one.  Personally, I
think that embedded graduate students should actually build one.  It
deepens the understanding like little else can.  But if the OP's
desire is to teach familiarity with commonly found commercial
operating systems, then there really is no question at all.

"Best practices" is also vague, Walter.  What's "best practices" in
general purpose commercial operating systems, such as Vista for
example, has very very little to do with what is "best practices" in
the embedded world.  I can, without risking too much, say that
"embedded is not Windows."  In fact, the skills required are exactly
as the OP has in fact said, that there exist enduring concepts, long
known, long tested, with clear and meaningful values in embedded and
that these enduring concepts are what should be taught.  That the OP
can then be better enabled for understanding the myriad complexity of
the real world by being fitted well with the key and central concepts
involved.

Finally, it's not so much the particular piece of software at the
school, but the teaching staff which makes a school world class and
best able to prepare their students.  You want students who can think
for themselves and push the envelope and create the next "best
practices."  That gets back to understanding well the enduring
concepts.  This is true for both embedded and otherwise.

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XINU and Minix.  And they are excellent for what they bite off.

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Yes, although I'd have to admit that these are not necessarily where
you'd learn to understand the internals of Vista, for example.  But
for embedded grad students, I'd imagine that XINU and Minix are each
excellent in their way.  I actually believe that any embedded student
should have fully read, page by page, the first XINU book and have
developed their own operating system from scratch without using the
source code available for XINU.  It's not hard to do.

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If I understand this last sentence, you are right.  It's fairly
obvious that the leading schools will be somewhat heavily involved in
research.  If they don't have a healthy research program going on,
it's probably not a top school.

Jon

Re: Req: (Free) Embedded Platforms for Education

Jon,

All of my comments need to be put in the context of software for
an advanced university level lab whose initial criterion was
"free and open source" (software) FOSS. In the original post both
the curriculum and the lab requirements list were missing and so the
thread has become what can they get for free and I assume the
course ware will be created around the availability of free tools.

My argument is a requirements list should be created first.


Jonathan Kirwan wrote:

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There was another thread to the conversation concerning reference
design material with either restrictive or non public licences. Major
customers generally are covered by a comprehensive contract
that licences reference material, technical information and use of silicon.
The argument was this same material is not easily licensed for other uses.

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I will agree, curriculum development does require effort and FOSS
is often out of date or the develops do not have the incentive to maintain
or continue product development.

The Universities have the responsibility to provide well developed material
to eager young students in return to the student tuition and grants that
they receive. At the extreme there is an ethics problem of trying to fulfil
a commitment with no cost sources as a higher priority than a clear list
of curriculum requirements. (I wonder if they have a law school)

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Solid curriculum foundations and good teaching staff.

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I agree. Minix has gone on to provide a social objective. I also know
why some really good commercial educational software ran to the
end of its useful life and was not replaced by developers skilled in
creating pedagogical materials. We are collectively at loss
because they are no longer there.

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Walter..


Re: Req: (Free) Embedded Platforms for Education
On Mon, 23 Jul 2007 18:29:04 -0400, Walter Banks

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I don't have the motivation to add much.  (Not in a bad way, just in
being able to find an appropriate and clear avenue to address.)  So I
will leave it here.

Thanks,
Jon

Re: Req: (Free) Embedded Platforms for Education
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It is perfectly fine for a silicon vendor to apply a non-free license to
code he supplies to users of his chips. But code that comes without any
license is unusable, and from my experience getting information on legal
topics is difficult if not impossible - support personell rarely wants to
risk giving any definitive legal advice, and sales isn't interested in
dealing with little or no revenue issues.

I never meant to imply that public domain would be better, I just wanted to
acknowledge that there could be code that has no "license" but is still
useable.

A good example in my opinion is the NicheLite TCP/IP stack for use with NXP
LPC23xx/24xx uCs. Before the download link they're asking you to read the
software license agreement, which clearly explains what you can, and what
you can't do. Of course you can think what you want of those restrictions,
but at least you know them.

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I understand the reasons why such code is licensed the way it is, but that
doesn't make the code any more useable if you don't want to risk being
locked in with that one tool vendor.
 
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I didn't care enough about the non-free variants of FreeRTOS, so I never
went to look at the OpenRTOS pages, I only looked at the "License feature
comparison" table, but yeah, you're right, the site really isn't that clear
on the non-free variants' licensing.
But then, apparently I have to acquire a license before I get the OpenRTOS
code, and I can only guess that during the process of acquiring that
license I can also have a look at it (the license).
On top of that, I can use the available GPLed code in-house for whatever I
want, it's only when it comes to distribution or when I need support that
the licensing options matter.

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That's why I'm strongly in favor of FSF approved free software licenses,
especially those that are listed as GPL compatible. But of course in that
case you could probably just use the GPL as is.

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Yeah, we all know that Linux is obsolete because monolithic kernels suck,
and microkernels are the next best thing (tm)... so much for "best
practices" and reality. Seriously, I don't see where free software is any
different from non-free software in that regard.
The advantage of free software is that it allows in-depth comparison of
different approaches.
 
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Searching for XINU (I've heard the acronym before, but never had a closer
look at it) brought me to the Wikipedia article that had a reference
to "Embedded XINU", and the LICENSE file from that download seems like a
very permissive free software license. No idea how a demand for "zero cost
no strings attached tools" could have lead to the disappearance of such
software.

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Re: Req: (Free) Embedded Platforms for Education



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This is an example of the down side of FOSS, this was an excellent piece
of software for education and I am sure that that the author got tired of the
100 emails a day each asking just one tiny support question. After weeks
of not being able to get anything done, put the whole thing in the public
domain just so the problems would go away. I'll bet they haven't, the flip
side is if he wanted to charge what it would actually cost to support XINU
there would be very loud screams of protest.

It's too bad he should have been encouraged to continue with a craft that
he is clearly good at but he had to choose to feed his family.


Walter Banks



Re: Req: (Free) Embedded Platforms for Education
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One could also say that even though the author got tired of supporting his
software, the permissive BSD-style license he used allowed others to
continue his valuable work.
Now imagine he would have used a less free license, one that allows use but
denies redistribution. If for whatever reason the author stopped caring
about his software, it would have been lost.

Best regards,

Dominic Rath

Re: Req: (Free) Embedded Platforms for Education
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If it was valuable perhaps he could have charged for it and continued to
develop it.  Why should he have to give his work away?

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With such a license he could have charged, earned living at it and
continued to develop it.  We would al have been better off.

It seems that FOSS Devotees are only happy when good engineers give
their work away for them to play with. As I keep saying FOSS values a
developers time and efforts at zero... so do most accountants these
days.


--
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\/\/\/\/\ Chris Hills  Staffs  England     /\/\/\/\/
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Re: Req: (Free) Embedded Platforms for Education
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I consider my own free software project valuable, and the growing number of
users seems to support this. I decided to release it under the terms of the
GPL because of all the things I like about free software, and because I
could afford it. Nothing forced me, I didn't have to give it away, it was
just my own decision. The project's success shows me it was the right thing
to do.

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That argument only works when you assume that it was a lack of money that
made him stop working on it, and if you assume the project would have
gained as much acceptance even if it wasn't licensed under a BSD style
license.
As it stands, the project was released under its free license, and even
though the original author apparently stopped maintaining it someone else
had the chance to take over.
 
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Sorry, but I really can't see what made you so bitter about free software.

Regards,

Dominic

Re: Req: (Free) Embedded Platforms for Education



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You have made a personal choice. Don't get me wrong there are a lot
of  clever ways to make money off free stuff. As the popularity of your
software grows other people will make money off that choice selling
advertising on hosted web sites incorporating it into products. You will
increasingly will be doing the not so interesting parts, answering emails
fixing code that could have been better written in the first place. More
exciting fun projects will appeal to a curious mind. You will start to
ask some very hard questions.

How is your project financially supported, who buys the computers and
pays the cost of developing and supporting the product? What happens
when you are forced to choose, are you going to make a career out of a
hobby like Jean Labrosse did with uc/OS-II or abandon it like others
have done. What is your responsibility to the users of your software after
you no longer want to support it?

When software is developed that needs to be supported out of the revenue
that is produced then two things happen very quickly. 1) The software will
die quickly if it doesn't fulfil a real need. or 2) It will continue to be
developed
with the specialized skills of the developer as long as it fills a need.

w..




Re: Req: (Free) Embedded Platforms for Education

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He answered your question here:

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He says he doesn't want to pay money and, even where that problem
might be bridged (by reducing the amount involved to something
meaningfully close to zero) by a negotiated arrangement, that he
doesn't want the complex relationships that such an arrangement often
requires.  It only takes one second of time, thinking like a professor
might, to understand his point.  And this provides his definition of
"free and open."

He'd already answered you.

Jon

Re: Req: (Free) Embedded Platforms for Education

So, in my case... I use M32C micros, and I build my own tools and
libraries from the sources I download from the FSF.  No fees, no
licenses, no arrangements of any sort.  I use a linux-based downloader
too.  This would be acceptable?  Heck, I'll even toss in my own
expansion board for the starterkit!  http://www.delorie.com/pcb/m3a /

The PIC tools are also gcc-based, one could extract those bits and
build a fee-less and arrangement-less set of tools for PIC from that.
Same for SH, ARM, AVR, and many others.

The tricky bit then is the amount of self-effort involved in taking
those bits and creating a consistent environment for the students to
learn in.

Re: Req: (Free) Embedded Platforms for Education

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Once the effort is expended and the process well documented for the
students, and tutors who may need to support them, it's a cut and
dried process.  Professors are routinely in the business of working
out the details of the curriculum so that it flows smoothly and well,
both for those students willing to work at it and for the teaching
staff (who are sincerely interested in not having to face the same
problems over and over again as it wastes their own time like little
else can.)

Jon

Re: Req: (Free) Embedded Platforms for Education

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Oh, I agree.  I'm just saying that there are tradeoffs; the complex
agreements and expensive packages buy you a bit of preparation that
you don't have to do.  OTOH, with FOSS you always have the option of
changing it, even if it's initially seems like "just the right thing".

I think there's a balance between "but I have to work on it to make it
right" and "but I *can* work on it to make it right" that the profs
(or anyone looking at FOSS) have to consider.  Me, I work on FOSS all
day long, so it's a no-brainer for me, but for someone with other
priorities...

Re: Req: (Free) Embedded Platforms for Education

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They usually are NOT tailored for teaching a class.  So I don't
believe this saves much in that regard.  The only thing it really does
is provide an operating manual and a library manual.  But none that
really replaces much in the curriculum development process.  Also,
since this is graduate level, as I understand it, there is a need for
depth and optional areas of specialization.  I'm really not sure how a
commercial operating system (I think that is still what we are talking
about, yes?) allows this -- I believe it requires access to the source
code for adaptation as part of the work.

XINU is probably an excellent example that was designed from the
ground up for teaching, possibly at the level that may be required
here.  And the books are nicely arranged for a course, as well.  This
is where I'd probably be thinking, myself.

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I suspect (but don't know, obviously) that the OP will require the
ability to change the operating system.  It's hard to imagine a
graduate level curriculum on embedded operating systems without that.

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Well, I've taught operating systems at the university level.  It was
for third year undergraduates, though.  I might consider using a
commercial system for first and second year teaching, because no one
is ready at that point to do much more than that.  By the third year,
though, in my operating systems and current programs course the
students had to delve somewhat deeply into concurrent programming and
operating system features needed to support that and had to simulate
various scheduling algorithms in somewhat general ways.  At a graduate
level, I'd expect a lot more than that.  And I cannot imagine not
needing access to the source for changes.

But I'm not designing this course, so I can't say what the OP actually
requires here.  But that's my take.

Jon

Re: Req: (Free) Embedded Platforms for Education
writes
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Like GPL?

The FOSS agreements are as bad as the ones for commercial SW

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Changing what? Lot of time and effort.... FOSS assumes you have
limitless time and it is costs  zero.



--
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
\/\/\/\/\ Chris Hills  Staffs  England     /\/\/\/\/
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