Re: [avr-gcc-list] XRAMEND & avr5.x

[Marek Michalkiewicz]

> Send this mail yesterday, but was not delivered 
> to me self, so i think this mail was lost in 
> space. If you got allready this mail, sorry... :-)

I received it, but if you're not getting other mails from the list,
spam protection at your ISP could be the problem.  I see this added
to the headers because majordomo2.host4u.net (209.150.128.179)
appears to be blacklisted in one of the RBLs:

X-RBL-Warning: (ztl.dorkslayers.com) Garst is nuke-on-sight. Everybody knows 
that.  Or should.  Enjoy your intranet.

Not sure who/what Garst is.  I don't block incoming mail based on RBLs
because that lets spam go through anyway, and blocks legitimate mail.

Spam is evil, but blocking innocent people for someone elses abuse is
evil too.  Some big ISPs abroad block *.sdi.tpnet.pl and forced me to
find someone nice enough to relay mail for me instead of delivering it
directly from my machine.

> How can I place data to external and 
> other variables to internal faster ram?

The current setup allows you to leave the stack in internal RAM and
start data in external RAM starting at 0x1100 by using the option:
avr-gcc -Wl,-Tdata,0x801100

To enable external SRAM at startup, you have to put a small piece of
asm code that writes MCUCR, in the .init2 section.

> I_m confused by the fact that only avr5.x is
> used as linker script whitout any definitions
> for XRAMEND? How do this work.

avr5.x allows the maximum memory sizes.  All you need is to initialize
MCUCR using a piece of code in the .init2 section, and pass -Tdata with
the correct start address to the linker, as shown above.  For simple
cases, there is no need to hack linker scripts anymore.

> Is there any document to understand all this
> nice stuff?

Not much, there should be... but for now, Use the Source Luke ;-)

Marek

avr-gcc-list at http://avr1.org