Tech Support > Computer Hardware > Microprocessors > Memory configuration
Memory configuration
Posted by roboman152 on February 21st, 2006


hello all,
Im having an odd issue if my LSB is a 1 I get a Data Abort fault.
Example:
Writing to 2FFFFFF0 works fine
Writing to 2FFFFFF1 causes the Data abort fault,
Which I can now say is what is been causing my problems with romboot.bin
because the second it tries to write to address 0x20000001 it dies an
causes my string of NAK on Sector errors. Suggestions? Im pretty muc
using the stock sources from romboot, I only changed the value for th
SDRAMC_CR register to match my SDRAMS row col settings, other than that
nothings changed...... Also Im using CroosTool's gcc build script to buil
the crosscompiler... although Id think if my compiler was no good, th
program would not run AT ALL.....
Suggestions?
Questions about something I should elaborate more on?
-Alex

ps - Thanks for ANY response... Im kinda stumped


Posted by Peter on February 21st, 2006



"roboman152" <amstewa2@ncsu.edu> wrote in message
news:e--dnUpFPbSAu2beRVn-og@giganews.com...
Maybe the processor needs aligned accesses, you failed to mention what your
hardware is. Perhaps the memory has a parity error? Did you switch on parity
by mistake?
Peter



Posted by roboman152 on April 21st, 2006


The hardware is a custom made AT91RM9200 board. And yes silly me I no
know it was a two fold problem, one was stray flux residue interferin
with the SDRAM clock, and also misalignment errors. So if it helps anyone
lesson learned --> ALWAYS CLEAN OFF YOUR FLUX
the interference was so bad my SDRAM clock line looked like a sine wave o
a scope :-) woops.