Re: [ECOS] Compiling eCOS with IAR

[Emmanuel Viollet <Emmanuel dot Viollet at webdyn dot com>]

Andrew Lunn a écrit :
> On Thu, May 11, 2006 at 01:32:53PM +0200, Emmanuel Viollet wrote:
>   
> > Hi.
> >
> > This may seem a stupid question, but is it possible to compile eCOS 
> > using the IAR compiler? From what I gather, IAR is much more efficient 
> > in terms of code space that GCC...
> >     
>
> It is unlikely IAR will work. eCos uses quite a few gcc extensions.
>
> If you need to make your application smaller i found that -Os has a
> big effect compared to -O2 which is the normal eCos default. Also gcc
> has been steadily getting better at producing smaller code. So try
> using gcc 4.1. If RAM is a problem try tuning your stacks. For some
> applications the default stack size is bigger than what is actually
> needed. There is code to monitor stack using you can turn on.
>
>   
I already tried compiling using -Os and I end up with lwIP taking up 
approx. 64Kb, zlib approx 27Kb, plus the kernel and my code, and all 
this is larger than the 128Kb of my EEPROM.
I also tried compiling using THUMB instructions, but GCC crashes while 
trying to compile eCOS in this mode.

I think this is going to end up by being forced to use IAR and a *very* 
small footprint RTOS like FreeRTOS. It's a pity, because I was beginning 
to like eCOS. I found it very complete.

Thanks for your help.


--
Emmanuel Viollet
Software engineer
Webdyn
e-mail : Emmanuel.Viollet@webdyn.com
Tel    : +33 (0)1 39 04 29 55


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