Reply by donald April 20, 20082008-04-20
ROB wrote:
> I have downloaded silRTOS source with its MIPS32 port and pretty happy with > its small code size. It took just few hours to grasp entire silRTOS and > infact within two day; i ran silRTOS with sample application on my custom > MIPS32 board.
http://silcomm.com/ The only way to get the source code is to send the author your email address , what is that all about !! donald
> > I got good impression and would encourage people to use silRTOS for: > > 1. Beginner of rtos who want to study RTOS & want to learn RTOS as source > code available. > > 2. Low-Footprint, which can be used for low memory embedded product. (Like > what i was looking) > > 3. Optimized RTOS and low Task switch/ISR latency, which make no over-head > for embedded application. > > 4. Different processor architectures RTOS port available. > > 5. Free to use for commercial project and needn't to give a single penny > or single line of code to silRTOS Author (Most important reason for me to > use) > > -Rob > >> On Apr 13, 8:31=A0pm, "ROB" <rob701...@yahoo.com> wrote: >>> Hi, >>> =A0 =A0I am new to any RTOS and wanted to learn more about it. Can some > po= >> st >>> me small & freely available RTOS with documents details & source code. >>> Also let me know, if these RTOS are absolutely FREE to use for > commercial >>> requirement. I am looking for small(<10KB), FREE(cost 0 cents), >>> popular(used readily) RTOS :-) >>> >>> Thanks in advance. >> I think your requirement ( Learn RTOS / Understand RTOS & use for >> free :-( ) matches with silRTOS from silcomm.com, which is free to use >> for commercial products, low foot print with open source & widely >> used. They provide document, sources & different processor port, which >> make it easy learn RTOS for newbie. silRTOS provides only basic >> services like vector ISR handling/Task handling/Sem/MessQ/Memory Mgmt >> with small size micro kernel. Even newbie can learn silRTOS within 1 >> day. >> >> I recently used silRTOS for vary same reason (free, open source & >> small... offcourse not for learning) on ARM & MIPS system and it is >> working beautifully for my complex embedded system. >> >> Also I believe that there could be other free RTOS available beside >> silrtos, which you may find by Googling :-) ... >> >> >>
Reply by CBFalconer April 20, 20082008-04-20
ROB wrote:
> > I have downloaded silRTOS source with its MIPS32 port and pretty > happy with its small code size. It took just few hours to grasp > entire silRTOS and infact within two day; i ran silRTOS with > sample application on my custom MIPS32 board. > > I got good impression and would encourage people to use silRTOS > for: > > 1. Beginner of rtos who want to study RTOS & want to learn RTOS > as source code available. > > 2. Low-Footprint, which can be used for low memory embedded > product. (Like what i was looking) > > 3. Optimized RTOS and low Task switch/ISR latency, which make no > over-head for embedded application. > > 4. Different processor architectures RTOS port available. > > 5. Free to use for commercial project and needn't to give a > single penny or single line of code to silRTOS Author (Most > important reason for me to use)
Thank you for your opinion. However, a couple of points about your article. Firstly, you should make some reference to the URL where you downloaded, without which no-one can follow you. Secondly, the act of top-posting has lost all the sequential information of the thread. Please do not top-post. Your answer belongs after (or intermixed with) the quoted material to which you reply, after snipping all irrelevant material. See the following links: <http://www.catb.org/~esr/faqs/smart-questions.html> <http://www.caliburn.nl/topposting.html> <http://www.netmeister.org/news/learn2quote.html> <http://cfaj.freeshell.org/google/> (taming google) -- [mail]: Chuck F (cbfalconer at maineline dot net) [page]: <http://cbfalconer.home.att.net> Try the download section. ** Posted from http://www.teranews.com **
Reply by ROB April 20, 20082008-04-20
I have downloaded silRTOS source with its MIPS32 port and pretty happy with
its small code size. It took just few hours to grasp entire silRTOS and
infact within two day; i ran silRTOS with sample application on my custom
MIPS32 board.

I got good impression and would encourage people to use silRTOS for:

1. Beginner of rtos who want to study RTOS & want to learn RTOS as source
code available.

2. Low-Footprint, which can be used for low memory embedded product. (Like
what i was looking)

3. Optimized RTOS and low Task switch/ISR latency, which make no over-head
for embedded application.

4. Different processor architectures RTOS port available.

5. Free to use for commercial project and needn't to give a single penny
or single line of code to silRTOS Author (Most important reason for me to
use)

-Rob

>On Apr 13, 8:31=A0pm, "ROB" <rob701...@yahoo.com> wrote: >> Hi, >> =A0 =A0I am new to any RTOS and wanted to learn more about it. Can some
po=
>st >> me small & freely available RTOS with documents details & source code. >> Also let me know, if these RTOS are absolutely FREE to use for
commercial
>> requirement. I am looking for small(<10KB), FREE(cost 0 cents), >> popular(used readily) RTOS :-) >> >> Thanks in advance. > >I think your requirement ( Learn RTOS / Understand RTOS & use for >free :-( ) matches with silRTOS from silcomm.com, which is free to use >for commercial products, low foot print with open source & widely >used. They provide document, sources & different processor port, which >make it easy learn RTOS for newbie. silRTOS provides only basic >services like vector ISR handling/Task handling/Sem/MessQ/Memory Mgmt >with small size micro kernel. Even newbie can learn silRTOS within 1 >day. > >I recently used silRTOS for vary same reason (free, open source & >small... offcourse not for learning) on ARM & MIPS system and it is >working beautifully for my complex embedded system. > >Also I believe that there could be other free RTOS available beside >silrtos, which you may find by Googling :-) ... > > >
Reply by Eric Smith April 17, 20082008-04-17
David Brown <david@westcontrol.removethisbit.com> writes:
> What he says in the article > that you quoted is that his opinions on allowing non-GPL kernel > modules does not count as a "get out of jail free" card. If you > distribute a blob kernel module, and someone challenges your right to > do so, it's up to *you* to defend it, not Linus.
Exactly my point. That's very far from saying that non-GPL kernel modules are "OK", yet many people seem to believe that Linus said that they are OK.
> The kernel has specific provisions for using non-GPL modules. These > include a restricted interface for modules that don't state that they > are GPL'ed, and "tainted" messages.
Though none of that actually provides any actual exception to the GPL license. IMNSHO, any entity distributing a non-GPL kernel module is taking a lot of risk, because there are literally thousands of people that have standing to bring a copyright infringement suit against said entity. Eric
Reply by David Brown April 17, 20082008-04-17
Eric Smith wrote:
> David Brown wrote: >> However, Linux also has provisions for >> linking non-GPL'ed modules into the kernel (not everyone agrees that >> this is allowed under the GPL, but Linus says it's okay). > > This kind of "Linus says it's okay" claim seems to be the prevailing > "wisdom", but no one ever seems to be able to cite any statement by > Linus that is anywhere near that broad. See, for example: > > http://lwn.net/Articles/13066/ > > Note that nowhere in that does Linus say outright that non-GPL'd modules > are OK, but rather suggests that if you want to distribute a non-GPL'd > module, you'd better be prepared to prove that it is not a derived work.
Linus is well-known for his pragmatism. He wants all kernel modules to be GPL'ed, but if a hardware supplier will only provide blob modules, he is not going to ban them. What he says in the article that you quoted is that his opinions on allowing non-GPL kernel modules does not count as a "get out of jail free" card. If you distribute a blob kernel module, and someone challenges your right to do so, it's up to *you* to defend it, not Linus. http://www.linuxdevices.com/news/NS3501846795.html The kernel has specific provisions for using non-GPL modules. These include a restricted interface for modules that don't state that they are GPL'ed, and "tainted" messages. Blob kernel modules do not have Linus' blessing, but they specifically and explicitly are not banned by him (though you will be cursed by RMS, of course).
Reply by Eric Smith April 16, 20082008-04-16
David Brown wrote:
> However, Linux also has provisions for > linking non-GPL'ed modules into the kernel (not everyone agrees that > this is allowed under the GPL, but Linus says it's okay).
This kind of "Linus says it's okay" claim seems to be the prevailing "wisdom", but no one ever seems to be able to cite any statement by Linus that is anywhere near that broad. See, for example: http://lwn.net/Articles/13066/ Note that nowhere in that does Linus say outright that non-GPL'd modules are OK, but rather suggests that if you want to distribute a non-GPL'd module, you'd better be prepared to prove that it is not a derived work.
Reply by CBFalconer April 16, 20082008-04-16
David Brown wrote:
>
... snip ...
> > The only major FOSS OS I know of that uses a pure GPL is Linux. > So if your code really needs critical modifications to the kernel, > you will have to publish those changes. However, Linux also has > provisions for linking non-GPL'ed modules into the kernel (not > everyone agrees that this is allowed under the GPL, but Linus > says it's okay). Of course, Linux itself is not hard realtime in > the first place - normally much of your code could go in user > space (if it is *that* time-critical, you should be looking at a > RTOS extension to Linux). > > For FOSS OS's under modified GPLs (such as FreeRTOS), you can > link your own non-GPL'ed files directly into the kernel. At > most, you might add a few hooks to the original source code.
The original owner (who hasn't given up rights) has many options, even though he has released the software under the GPL (or equivalent). For example, I have released hashlib uner the GPL, but the documentation specifies that other licensing rights can be bought. So, for a fee, I can release the user from the obligation to release his source code. Hashlib adheres to the C standard, and so is fully portable. See: <http://cbfalconer.home.att.net/download/> -- [mail]: Chuck F (cbfalconer at maineline dot net) [page]: <http://cbfalconer.home.att.net> Try the download section. ** Posted from http://www.teranews.com **
Reply by David Brown April 16, 20082008-04-16
cs_posting@hotmail.com wrote:
> On Apr 15, 9:08 am, John Devereux <jdREM...@THISdevereux.me.uk> wrote: > >> But in fact most free RTOSs are *not* GPL licenced, (as David Brown >> pointed out). Even programs that are (like e.g. linux) do not require >> publishing "all your source code", just the parts that link to the >> kernel. So you could build or buy hardware supported by linux, and >> install your own proprietary software on to it. But if you need to >> modify the kernel (e.g. write a special device driver) you would need >> to publish *that*. > > I would expect that the more hard-realtime parts of your system may > need to link to the > kernel in ways that may cause the GPL to apply to those parts. > > However, you may be able to do the realtime parts in kernel modules, > but keep a lot of other parts of the system in proprietary userspace > code.
The only major FOSS OS I know of that uses a pure GPL is Linux. So if your code really needs critical modifications to the kernel, you will have to publish those changes. However, Linux also has provisions for linking non-GPL'ed modules into the kernel (not everyone agrees that this is allowed under the GPL, but Linus says it's okay). Of course, Linux itself is not hard realtime in the first place - normally much of your code could go in user space (if it is *that* time-critical, you should be looking at a RTOS extension to Linux). For FOSS OS's under modified GPLs (such as FreeRTOS), you can link your own non-GPL'ed files directly into the kernel. At most, you might add a few hooks to the original source code.
Reply by April 16, 20082008-04-16
On Apr 15, 9:08 am, John Devereux <jdREM...@THISdevereux.me.uk> wrote:

> But in fact most free RTOSs are *not* GPL licenced, (as David Brown > pointed out). Even programs that are (like e.g. linux) do not require > publishing "all your source code", just the parts that link to the > kernel. So you could build or buy hardware supported by linux, and > install your own proprietary software on to it. But if you need to > modify the kernel (e.g. write a special device driver) you would need > to publish *that*.
I would expect that the more hard-realtime parts of your system may need to link to the kernel in ways that may cause the GPL to apply to those parts. However, you may be able to do the realtime parts in kernel modules, but keep a lot of other parts of the system in proprietary userspace code.
Reply by Eric Smith April 16, 20082008-04-16
FreeRTOS.org wrote:
> But to those of you who > think you can write an operating system in a weekend, well, it's clear that > just writing the tests will consume far more time than that.
Writing tests? Why would I do that? If there are bugs, my customers will report them. [There are far too many companies that have that attitude.]