[ECOS] how to configure eCos small enough to run on at91sam7s64

Andrew Lunn andrew@lunn.ch
Wed May 27 06:52:00 GMT 2009

On Wed, May 27, 2009 at 02:09:59PM +0800, wb ning wrote:
> Hello all,
> I am only start to use eCos. And now i have setup my own environment,
> that's cygwin + eCos.
> Next Step i should configure it using Configuration Tools.exe. There
> is a template of Atmel AT91SAM7SEK evaluation board came with the
> distribution yet.
> But because sam7s64 has very limited ROM size (64KB), I should make
> some changes to suit this small size. Unload some useless Package.. or
> something like that.  But I found even there is no conflict when i
> unload some packages. Errors would occur at Make time. That's really a
> tricky for a new user, Besides the remain size of the image is still
> very large, about 130K,
> Can anyone give some help about how to configuration it with no making
> errors happened?

$ ecosconfig new at91sam7sek minimal
U CYGHWR_HAL_ARM_AT91, new inferred value AT91SAM7S
U CYGHWR_HAL_ARM_AT91_FIQ, new inferred value 1
lunn@londo:~/eCos/work$ ecosconfig add i2c
$ ecosconfig tree
lunn@londo:~/eCos/work$ make -s
headers finished
/home/lunn/eCos/anoncvs-clean/packages/hal/arm/at91/var/current/src/hal_diag.c: In function 'cyg_hal_plf_serial_isr':
/home/lunn/eCos/anoncvs-clean/packages/hal/arm/at91/var/current/src/hal_diag.c:260: warning: pointer targets in passing argument 1 of 'cyg_hal_is_break' differ in signedness
build finished

This is as about as small as you can get without digging too deep.
Yes, it can be smaller, but that requires more understanding of eCos.

> or someone has the xx.ecc for at91sam7s64 that suit
> my need? Time is press for me to find out the minmum size of the eCos
> image, ( the eCos only need to support serial port, TWI, ADC)

There is no ADC support for AT91SAM7 platforms at the moment. You will
need to write your own driver.

Also, remember that you need to use arm-elf-size to look at the
code/data size, not the size of the elf image.


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

More information about the Ecos-discuss mailing list