This is the mail archive of the ecos-discuss@sourceware.org mailing list for the eCos project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: Required code & data sizes


In gmane.os.ecos.general, you wrote:

> We are designing a new product where we wants to use eCOS for
> the first time. The design should be based on the ARM
> processor from ST, STR710 with 128KByte codeflash and 32KByte
> Ram. The product will have 2-3 serial port running small and
> simple serial protocols and a 10/100MBit ethernet port - No
> grafical interface.

That's not enough memory to do anything useful with eCos and
the BSD TCP/IP stack.  Switching to the LWIP stack might save
enough memory to get something running, but you'd be starting
out with 30-50% of your code space taken up by the kernel.

> We have read a lot of articles in the internet and the book
> written by A. Massa, but no where have we found any
> information on how big the code area should be (only estimated
> sizes of course). We have read that it should be posible to
> make a bootable image on 30-40 KB code, but what about the
> TCP/IP part and what about the required RAM.

[I've only used the BSD TCP/IP stack -- so these numbers are
for that stack.]

If you want to run TCP/IP, you should allocate about 64KB of
RAM for buffer space space per open socket.  You might be able
to get by with 32KB of buffer space per socket, but that would
be pretty slim. 

The kernel will probably be 48-64KB of code space.  The
network stack is around around 128KB of code space.

For what you're doing, I would guess you'd need a minimum of
256KB of code space and 128KB of data space to get started
(that doesn't include a lot of memory for your application).


-- 
Grant Edwards                   grante             Yow!  HOORAY, Ronald!! Now
                                  at               YOU can marry LINDA
                               visi.com            RONSTADT too!!

-- 
Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos
and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]