[ECOS] Re: Atmel AT91 EB40 port

[Andreas Andersson <e92_aan at e dot kth dot se>]

On Wed, 1 Aug 2001 (in ecos-announce), Jonathan Larmour wrote:

> eCos has now been enhanced with a port to the Atmel AT91-based EB40
> evaluation board. This port, currently a beta, includes RedBoot support,
> Flash and serial drivers. Source code is available from the development
> repository accessible via anonymous CVS.
> 
> More details including prebuilt RedBoot binaries are available from 
> http://sources.redhat.com/ecos/boards/at91eb40.html
> 
> Some developers may now be interested in ports to some of the other very
> similar Atmel evaluation kits such as the EB01 or EB63. Red Hat would
> welcome contributions from the net community for ports to these boards.

Well, I can tell you that it doesn't work out of the box with my EB01,
but that's almost certainly because of a spurious interrupt bug that has
haunted me for a long time. (The board has an _early_ revision processor.)

Otherwise I don't see any reason why it wouldn't go. The memory layout
in the port is the same as one I'm using on a project and the only
differences in the processors are the larger internal memory (which
you haven't made use of yet anyway) and some power saving features that
the R40807 has which I think are just missing, i.e. does nothing, on the
M40400.

The setup code seems like it should be just fine on both processors,
although one comment threw me off a bit at first:

   ldr     r0,=0x01010000          // Relocate FLASH/ROM to on-chip RAM
   ldr     r1,=0x02000000          // RAM base & length

The secondary on-chip SRAM should appear at 0x00100000 after remap,
0x02000000 and forward is external SRAM. A minor nitpick, but anyway...

I don't know how all this would work with the EB63, though. It does seem
a bit different from the others, but I haven't had any hands on experience
with it...

> Please send any comments to ecos-discuss@sources.redhat.com. Thanks!

No, thank you! (Or rather, Gary Thomas? :)

/Andreas