RTOS porting

Hi,
    Can any one tell me how to start porting a RTOS on ARM. I mean what
exactly should i Study to port a RTOS. 
Thank You.
Abhiraj

"abhiraj11" <abhiraj11@yahoo.com> schreef in bericht 
news:_ZOdnb1WGJYtZhfeRVn-iQ@giganews.com...
> Hi,
>    Can any one tell me how to start porting a RTOS on ARM. I mean what
> exactly should i Study to port a RTOS.

I'm not a porting expert, but I think I have a few useful clues for you:

- Make sure that it isn't already ported.
- Determine how portable the various parts of RTOS code are.
- Use as much as possible a high level language like C.
- Use a popular compiler/assembler/linker toolchain.
- Get a popular reference board, a popular JTAG debugger and a popular IDE 
that supports your toolchain and debugger.
- Look at standalone sample IDE projects for ARM and for architectures that 
you are familiar with.
- Look at RTOS sample IDE projects for ARM and for architectures that you are 
familiar with.
- Look at other ports of the RTOS.
- Look at other RTOSes ported to ARM.

BTW, which RTOS are we talking about?

On Mon, 28 Nov 2005 18:09:09 +0100, "Boudewijn Dijkstra"
<usenet@bdijkstra.tmfweb.nl> wrote:

>"abhiraj11" <abhiraj11@yahoo.com> schreef in bericht 
>news:_ZOdnb1WGJYtZhfeRVn-iQ@giganews.com...
>> Hi,
>>    Can any one tell me how to start porting a RTOS on ARM. I mean what
>> exactly should i Study to port a RTOS.
>
>I'm not a porting expert, but I think I have a few useful clues for you:
>
>- Make sure that it isn't already ported.
>- Determine how portable the various parts of RTOS code are.
>- Use as much as possible a high level language like C.
>- Use a popular compiler/assembler/linker toolchain.
>- Get a popular reference board, a popular JTAG debugger and a popular IDE 
>that supports your toolchain and debugger.
>- Look at standalone sample IDE projects for ARM and for architectures that 
>you are familiar with.
>- Look at RTOS sample IDE projects for ARM and for architectures that you are 
>familiar with.
>- Look at other ports of the RTOS.
>- Look at other RTOSes ported to ARM.
>
>BTW, which RTOS are we talking about?

Since some (small?) portion of the RTOS is likely to be written in
assembly language, study the ported-from architecture and its
instruction set(s) in addition to the same for the ARM.
-- 
Dan Henry

"abhiraj11" <abhiraj11@yahoo.com> wrote in message
news:_ZOdnb1WGJYtZhfeRVn-iQ@giganews.com...
> Hi,
>     Can any one tell me how to start porting a RTOS on ARM. I mean what
> exactly should i Study to port a RTOS.
> Thank You.
> Abhiraj
>

The FreeRTOS WEB site has reproduced a report written by two students that
details their porting efforts.  Take a look at the ColdFire port pages, also
the "How FreeRTOS Works" might be of interest.    URL in signature below.

Regards,
Richard.

http://www.FreeRTOS.org

Your development board should come with startup assembler code for
getting RAM, etc. to work.  And your compiler vender should give you
the rest to get a c/c++ environment up & running.  I always get a small
c/c++ program up & running first.  Then, I port the RTOS.  Note, each
RTOS has it's own porting guide.

If you lack experience with an RTOS, you might find the book
MicroC/OS-II by Labrosse helpful.  It's a real small RTOS and I'm sure
it's been ported to arm.

Jim