Re: [ECOS] Use of internal and external ram

["Lewin A.R.W. Edwards" <larwe@larwe.com>]

Hi Stanley,

>I am building eCos for AT91EB40

Question: Where did you get the sources for this? Is this the old archived 
port mentioned on ecos-discuss some weeks ago, or are you collaborating 
with Daniel Andersson, or are you developing an independent port?

>In my platform there is internal ram(addr 0x00100000) and external ram(addr
>0x02000000) how do I make use of both available ram?
>Is it possible to specify that the stack space resides in the internal ram
>while data in external ram?

It's certainly possible (I do something very similar on the EP7212 - user, 
FIQ, IRQ, SVC stacks are in on-chip SRAM and heap is in off-chip DRAM). 
It's just a matter of tinkering with the startup code and linker script. 
For elegant integration into eCos, especially given that most people who 
use it are going to port it to "real" hardware sometime, I would suggest 
that you expose this stuff to configtool if possible.

=== Lewin A.R.W. Edwards (Embedded Engineer)
Work: http://www.digi-frame.com/
Personal: http://www.zws.com/ and http://www.larwe.com/

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