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RE: 32 Meg sdram



> Mark Schapira wrote:
> > are doing this by replacing the 16 Meg ram chip on our 
> board with a 32
> > Meg ram chip. We have recompiled the kernel to accomodate 
> the 32 Megs
> 
> It's not that simple, at least 16 bit 32 MiB chips have one 
> more address
> line than 16 MiB chips, so you have to take care of that. And 
> you have to
> change the sdram_config register accordingly, see chapter 19 
> of Etrax100LX
> designers reference.
> Just draw the address bits for 32 MiB on paper, divide them to
> column/row/bank select lines (see sdram datasheet) and 
> calculate bit shift
> values for the config register.
> I think I once saw a howto-like document about this on the 
> Axis website.

If you really are using SDRAM and not DRAM, here it is: <http://developer.axis.com/doc/hardware/etrax100lx/SDRAM_design.html>

> 
> Good luck with the calculations.
>

To be less dependent of luck, fill in and submit the form at the
bottom of this page:
<http://developer.axis.com/doc/hardware/etrax100lx/sdram_config/>
and a cgi-script will calculate the value of R_SDRAM_CONFIG for you.

Best regards
/Jonas