Reply by subhasish September 14, 20082008-09-14
On Sep 11, 7:39=A0pm, "Not Really Me"
<sc...@validatedQWERTYsoftware.XYZZY.com> wrote:
> "oe1gca" <g.chva...@adcon.at> wrote in message > > news:EZCdnQseXbpxhFXVnZ2dnUVZ_rHinZ2d@giganews.com... > > > Hi! > > > With our current SDRAM initialization (in our boot code), sometimes the > > SDRAM does not work correctly after power-up reset. Every second quad-w=
ord
> > can't be accessed (it seems that it can't be written). > > > When the SDRAM is in this erroneous state after power-up, repetitive > > resets (not power-up) won't resolve the problem. Only a power-off/on cy=
cle
> > will resolve the problem. > > > So I think, something is missing or wrong in the initialization sequenc=
e.
> > > We are using a Technologic Systems TS-7200 board with an EP9302 CPU. > > The initialization code we took is from the Open TS-72XX system boot > > code. > > > The datasheet of the SDRAM does not cover the initialization sequence. > > > Any ideas? > > > Thank you in advance! > > Gerhard > > This seems to be their generic initialization guide.http://www.samsung.co=
m/global/business/semiconductor/products/dram/do...
> > Scott
This could very well be a hardware issue on your board. Probe the board when it goes into the erronous state, check the voltages and clock. Look for gliches also
Reply by Not Really Me September 11, 20082008-09-11
"oe1gca" <g.chvatal@adcon.at> wrote in message 
news:EZCdnQseXbpxhFXVnZ2dnUVZ_rHinZ2d@giganews.com...
> Hi! > > With our current SDRAM initialization (in our boot code), sometimes the > SDRAM does not work correctly after power-up reset. Every second quad-word > can't be accessed (it seems that it can't be written). > > When the SDRAM is in this erroneous state after power-up, repetitive > resets (not power-up) won't resolve the problem. Only a power-off/on cycle > will resolve the problem. > > So I think, something is missing or wrong in the initialization sequence. > > We are using a Technologic Systems TS-7200 board with an EP9302 CPU. > The initialization code we took is from the Open TS-72XX system boot > code. > > The datasheet of the SDRAM does not cover the initialization sequence. > > > Any ideas? > > > Thank you in advance! > Gerhard > > >
This seems to be their generic initialization guide. http://www.samsung.com/global/business/semiconductor/products/dram/downloads/sdr_device_operation_jul_06.pdf Scott
Reply by oe1gca September 10, 20082008-09-10
Hi!

With our current SDRAM initialization (in our boot code), sometimes the
SDRAM does not work correctly after power-up reset. Every second quad-word
can't be accessed (it seems that it can't be written).

When the SDRAM is in this erroneous state after power-up, repetitive
resets (not power-up) won't resolve the problem. Only a power-off/on cycle
will resolve the problem.

So I think, something is missing or wrong in the initialization sequence.

We are using a Technologic Systems TS-7200 board with an EP9302 CPU.
The initialization code we took is from the Open TS-72XX system boot
code.

The datasheet of the SDRAM does not cover the initialization sequence.


Any ideas?


Thank you in advance!
Gerhard