Hi All,
   
  I have one problem about memory. When I am trying to write in EXTMEM I do not have problem
but I have problem when I am reading same data from external memory. I do not see it as same
data as I save it. For example: if  I write  data in external memory and 
  if I read it it read first byte then 5th byte then 2nd then 6th, and so on. I found out that
if I am writing data as float data type I can read it without any problem, it means I read same
data I wrote. 
   
  Does anyone know how to solve this problem? Or if anyone hase suggestion it is welcome.
  Is there any other way to read data and to get correct value?
   
  Thanks,
  Ado

Moranjkic-

>   I have one problem about memory. When I am trying to write in EXTMEM I do not
> have problem but I have problem when I am reading same data from external memory.
> I do not see it as same data as I save it. For example: if  I write  data in
> external memory and
>   if I read it it read first byte then 5th byte then 2nd then 6th, and so on.
> I found out that if I am writing data as float data type I can read it without
> any problem, it means I read same data I wrote.
> 
>   Does anyone know how to solve this problem? Or if anyone hase suggestion it
> is welcome.
>   Is there any other way to read data and to get correct value?

If you can write 32-bit data Ok but not 16-bit or 8-bit data, then I suggest to
carefully check the byte-enable lines from 55x to the SDRAM (or SRAM) devices.  These
are lines labeled /EMIF_BEn on the 55x and typically labeled something like /BLE and
/BHE (for 16-bit wide mem device).

For example, if all /BLE and /BHE lines (2 on each x16 chip) are GND instead of
connected to DSP, then you would get exactly the problem you describe.

-Jeff

Adnan-
> Your suggestion is great. Thank you.
>
> Could you give me more directions? Or could you explain it to more?
>
> I am working on OMAP5910 (TMS320C55xx) and I cannot find more information and
> documentation about C55xx external memory, that is related to my problem.

First, which 55x device is it?  You have to know the exact core type, as there are
significant differences between EMIF for 5502/3, 5507, 5509, 5510, etc.

Second, try to find an "EMIF Reference Guide" document for your core type on TI's
website.  For example, this document:

  http://focus.ti.com/lit/ug/spru621f/spru621f.pdf

is valid for 5502/3.

-Jeff

PS. Please post to the group, not to me.
> Jeff Brower <j...@signalogic.com> wrote:
>
>      Moranjkic-
>
>      > I have one problem about memory. When I am trying to write in EXTMEM I
>      do not
>      > have problem but I have problem when I am reading same data from
>      external memory.
>      > I do not see it as same data as I save it. For example: if I write data
>      in
>      > external memory and
>      > if I read it it read first byte then 5th byte then 2nd then 6th, and so
>      on.
>      > I found out that if I am writing data as float data type I can read it
>      without
>      > any problem, it means I read same data I wrote.
>      >
>      > Does anyone know how to solve this problem? Or if anyone hase
>      suggestion it
>      > is welcome.
>      > Is there any other way to read data and to get correct value?
>
>      If you can write 32-bit data Ok but not 16-bit or 8-bit data, then I
>      suggest to
>      carefully check the byte-enable lines from 55x to the SDRAM (or SRAM)
>      devices. These
>      are lines labeled /EMIF_BEn on the 55x and typically labeled something
>      like /BLE and
>      /BHE (for 16-bit wide mem device).
>
>      For example, if all /BLE and /BHE lines (2 on each x16 chip) are GND
>      instead of
>      connected to DSP, then you would get exactly the problem you describe.
>
>      -Jeff
>

--- In c...@yahoogroups.com, Jeff Brower <jbrower@...> wrote:
>
> Moranjkic-
> 
> >   I have one problem about memory. When I am trying to write in
EXTMEM I do not
> > have problem but I have problem when I am reading same data from
external memory.
> > I do not see it as same data as I save it. For example: if  I
write  data in
> > external memory and
> >   if I read it it read first byte then 5th byte then 2nd then 6th,
and so on.
> > I found out that if I am writing data as float data type I can
read it without
> > any problem, it means I read same data I wrote.
> > 
> >   Does anyone know how to solve this problem? Or if anyone hase
suggestion it
> > is welcome.
> >   Is there any other way to read data and to get correct value?
> 
> If you can write 32-bit data Ok but not 16-bit or 8-bit data, then I
suggest to
> carefully check the byte-enable lines from 55x to the SDRAM (or
SRAM) devices.  These
> are lines labeled /EMIF_BEn on the 55x and typically labeled
something like /BLE and
> /BHE (for 16-bit wide mem device).
> 
> For example, if all /BLE and /BHE lines (2 on each x16 chip) are GND
instead of
> connected to DSP, then you would get exactly the problem you describe.
> 
> -Jeff
>
Hi All,

I just want to say that this forum give me great advices.
I want to thank Jeff.

Thanks
Adnan Moranjkic