[ECOS] Use of internal and external ram

[ECOS] Use of internal and external ram

[Ho Shui Choy Stanley PS03B NCS]

I am building eCos for AT91EB40
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?

Thanks
Stanley

Re: [ECOS] Use of internal and external ram

[Lewin A.R.W. Edwards]

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/

"... a man who is endowed with real qualities of leadership will be tempted 
to refrain from taking part in political life; because [...] the situation 
does not call for a man who has a capacity for constructive statesmanship 
but rather for a man who is capable of bargaining for the favour of the 
majority. Thus the situation will appeal to small minds and will attract 
them accordingly."

[ECOS] IO Streams

[Andy Simpkins]

Hi there,

Does anyone use libiostream with eCos?
If so what steps do I need to take to use it?

If not does eCos support IO streams and if so what do I need to use and what
files do I need to look at?

I don't fully understand the subject yet so please go gently with any reply!

Kind regards

Andy