Re: [ECOS] eCos info

[Andrew Lunn <andrew at lunn dot ch>]

On Sun, Sep 02, 2007 at 11:35:47PM +0200, Meiring, H, Mnr <meiring@sun.ac.za> wrote:
> 
> Hi all,
> 

> What protection does eCos provide for MMU-less micro controllers,
> for example when a process want to do memory altering outside its
> permitted allocation area, and for that matter to protect itself
> (the OS)

eCos performance no memory protection at all. For deeply embedded
systems, which eCos is target at, it is considered unnecessary
overhead.
 
> I have some simple questions regarding the HAL layer of eCos after
> reading A Massa?s book on eCos. Redboot and eCos use the same
> HAL. If redboot is compiled for ROM mode it produces a binary image
> that is structured as defined on page 187, which include a HAL layer
> and device drivers. Now if you compile the eCos default template, it
> results in a library that contains the HAL and device drivers as
> well? Resulting in 2 identical sets of HAL?s and device drivers? Is
> this correct, or do I have the integration of it incorrect? And is
> it possible to end with one HAL and device driver set?

The ROM mode application and the RAM mode application each are
complete. Each has its own eCos.

> I want to load ecos and a couple of applications and be allowed at a
> later stage to upgrade 1 or more of the applications without having
> to load eCos with it again as shown in the example provided (I will
> have very limited bandwidth and connection time to do upgrade).

> I want to use reboot(purely as a bootloader), what optimization can
> be done (with regards to Compiler settings and feature removal) once
> the development is done and the system is to be built for production
> purposes ? ie no debug.  I removed the ?g option from the compiler
> options and it reduced the image size significantly, any other
> recommendations?

Take a read of the man page for size, arm-elf-size. My guess is you
are looking at the size of the elf, not the size of the image. -g
should only make a small difference.

You should be able to remove the GDB stubs.

    Andrew

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