Hi,
Does anyone know the reason of using SDRAM and NAND flash on 9260-EK instead of
combination of parallel flash and SRAM?
I am thinking to connect parallel flash and SRAM to the 9260's EBI
interface.
I believe SRAM will give better performance in terms of accessing speed. Any
comments?
Regards
Phuah
Memory Configuration on AT91SAM9260-EK board.
Started by ●November 28, 2007
Reply by ●November 28, 20072007-11-28
Phuah,
It's a question of cost and performance. A 4 MB NOR (parallel) flash
will run you about $8-$10. 64MB of SDRAM + 64MB of NAND flash will
run you maybe $6. (Depends on quantities, etc, but this is a
ballpark). So for large-memory systems, the NAND/SDRAM combination is
MUCH cheaper. Also, for the small penalty of copying from flash to
ram you get the better performance of the RAM (so everything runs
faster, too).
--- In A..., yh.phuah@... wrote:
>
> Hi,
>
> Does anyone know the reason of using SDRAM and NAND flash on 9260-EK
instead of combination of parallel flash and SRAM?
>
> I am thinking to connect parallel flash and SRAM to the 9260's EBI
interface.
> I believe SRAM will give better performance in terms of accessing
speed. Any comments?
>
> Regards
> Phuah
>
It's a question of cost and performance. A 4 MB NOR (parallel) flash
will run you about $8-$10. 64MB of SDRAM + 64MB of NAND flash will
run you maybe $6. (Depends on quantities, etc, but this is a
ballpark). So for large-memory systems, the NAND/SDRAM combination is
MUCH cheaper. Also, for the small penalty of copying from flash to
ram you get the better performance of the RAM (so everything runs
faster, too).
--- In A..., yh.phuah@... wrote:
>
> Hi,
>
> Does anyone know the reason of using SDRAM and NAND flash on 9260-EK
instead of combination of parallel flash and SRAM?
>
> I am thinking to connect parallel flash and SRAM to the 9260's EBI
interface.
> I believe SRAM will give better performance in terms of accessing
speed. Any comments?
>
> Regards
> Phuah
>
Reply by ●November 29, 20072007-11-29
--- In A..., "twgbonehead" wrote:
>
> Phuah,
>
> It's a question of cost and performance. A 4 MB NOR (parallel) flash
> will run you about $8-$10. 64MB of SDRAM + 64MB of NAND flash will
> run you maybe $6. (Depends on quantities, etc, but this is a
> ballpark). So for large-memory systems, the NAND/SDRAM combination is
> MUCH cheaper. Also, for the small penalty of copying from flash to
> ram you get the better performance of the RAM (so everything runs
> faster, too).
> --- In A..., yh.phuah@ wrote:
> >
> > Hi,
> >
> > Does anyone know the reason of using SDRAM and NAND flash on 9260-EK
> instead of combination of parallel flash and SRAM?
> >
> > I am thinking to connect parallel flash and SRAM to the 9260's EBI
> interface.
> > I believe SRAM will give better performance in terms of accessing
> speed. Any comments?
> >
> > Regards
> > Phuah
>
NAND flash support on AT91SAM9260 is on CS3 only. Since NAND flash is
not connected to CS0 hence it is impossible for us too boot from NAND
when BMS = 0 (Boot on External Memory).
To boot from NAND flash we must set BMS =1 and let the ROM program to
detect NAND flash then boot from the NAND. Am I correct?
Thank You
>
> Phuah,
>
> It's a question of cost and performance. A 4 MB NOR (parallel) flash
> will run you about $8-$10. 64MB of SDRAM + 64MB of NAND flash will
> run you maybe $6. (Depends on quantities, etc, but this is a
> ballpark). So for large-memory systems, the NAND/SDRAM combination is
> MUCH cheaper. Also, for the small penalty of copying from flash to
> ram you get the better performance of the RAM (so everything runs
> faster, too).
> --- In A..., yh.phuah@ wrote:
> >
> > Hi,
> >
> > Does anyone know the reason of using SDRAM and NAND flash on 9260-EK
> instead of combination of parallel flash and SRAM?
> >
> > I am thinking to connect parallel flash and SRAM to the 9260's EBI
> interface.
> > I believe SRAM will give better performance in terms of accessing
> speed. Any comments?
> >
> > Regards
> > Phuah
>
NAND flash support on AT91SAM9260 is on CS3 only. Since NAND flash is
not connected to CS0 hence it is impossible for us too boot from NAND
when BMS = 0 (Boot on External Memory).
To boot from NAND flash we must set BMS =1 and let the ROM program to
detect NAND flash then boot from the NAND. Am I correct?
Thank You
Reply by ●December 6, 20072007-12-06
Phuah,
You should read the errata carefully for this part. I'm more familiar
with the 9263, but I think the internal ROM bootstrap can ONLY boot
from an atmel dataflash, regardless of the description in the
datasheet. Booting from NAND Flash or CompactFlash doesn't work.
(Yes, they give you 10 pages of description on how the boot program is
SUPPOSED to work, and then bury, at the very end of the document, the
fact that it is totally broken!)
--- In A..., "yh.phuah" wrote:
>
> --- In A..., "twgbonehead" wrote:
> >
> > Phuah,
> >
> > It's a question of cost and performance. A 4 MB NOR (parallel) flash
> > will run you about $8-$10. 64MB of SDRAM + 64MB of NAND flash will
> > run you maybe $6. (Depends on quantities, etc, but this is a
> > ballpark). So for large-memory systems, the NAND/SDRAM combination is
> > MUCH cheaper. Also, for the small penalty of copying from flash to
> > ram you get the better performance of the RAM (so everything runs
> > faster, too).
> >
> >
> > --- In A..., yh.phuah@ wrote:
> > >
> > > Hi,
> > >
> > > Does anyone know the reason of using SDRAM and NAND flash on 9260-EK
> > instead of combination of parallel flash and SRAM?
> > >
> > > I am thinking to connect parallel flash and SRAM to the 9260's EBI
> > interface.
> > > I believe SRAM will give better performance in terms of accessing
> > speed. Any comments?
> > >
> > > Regards
> > > Phuah
> > >
> > NAND flash support on AT91SAM9260 is on CS3 only. Since NAND flash is
> not connected to CS0 hence it is impossible for us too boot from NAND
> when BMS = 0 (Boot on External Memory).
>
> To boot from NAND flash we must set BMS =1 and let the ROM program to
> detect NAND flash then boot from the NAND. Am I correct?
> Thank You
>
You should read the errata carefully for this part. I'm more familiar
with the 9263, but I think the internal ROM bootstrap can ONLY boot
from an atmel dataflash, regardless of the description in the
datasheet. Booting from NAND Flash or CompactFlash doesn't work.
(Yes, they give you 10 pages of description on how the boot program is
SUPPOSED to work, and then bury, at the very end of the document, the
fact that it is totally broken!)
--- In A..., "yh.phuah" wrote:
>
> --- In A..., "twgbonehead" wrote:
> >
> > Phuah,
> >
> > It's a question of cost and performance. A 4 MB NOR (parallel) flash
> > will run you about $8-$10. 64MB of SDRAM + 64MB of NAND flash will
> > run you maybe $6. (Depends on quantities, etc, but this is a
> > ballpark). So for large-memory systems, the NAND/SDRAM combination is
> > MUCH cheaper. Also, for the small penalty of copying from flash to
> > ram you get the better performance of the RAM (so everything runs
> > faster, too).
> >
> >
> > --- In A..., yh.phuah@ wrote:
> > >
> > > Hi,
> > >
> > > Does anyone know the reason of using SDRAM and NAND flash on 9260-EK
> > instead of combination of parallel flash and SRAM?
> > >
> > > I am thinking to connect parallel flash and SRAM to the 9260's EBI
> > interface.
> > > I believe SRAM will give better performance in terms of accessing
> > speed. Any comments?
> > >
> > > Regards
> > > Phuah
> > >
> > NAND flash support on AT91SAM9260 is on CS3 only. Since NAND flash is
> not connected to CS0 hence it is impossible for us too boot from NAND
> when BMS = 0 (Boot on External Memory).
>
> To boot from NAND flash we must set BMS =1 and let the ROM program to
> detect NAND flash then boot from the NAND. Am I correct?
> Thank You
>
