I've just checked the exact number of bytes which can be writen in 1 time,
it seems to be 64 bytes, exactly the size of the internal buffer of the EMC.
After writing these bytes I have to wait several minutes before writing other
bytes, otherwise the RAM content is scrumbled up...
So writing to RAM takes a lot of time, is this normal??
Any ideas are welcome, thanks.
Regards,
Nico
--- In l..., "Nico Bollen" wrote: >
> Herbert,
>
> I've read those postings.
> It's very difficult to find the correct value but I think I have followed
all rules...
> In the meanwhile I also tried 0x33<<10 and 0x33<<12, with both combinations
the behaviour was the same.
>
> Thanks
> Nico
> --- In l..., Herbert Demmel wrote:
> >
> > Nico,
> >
> > did you have a look to earlier postings about SRAM in this group ?
> >
> > If you have a wrong value in
> >
> > dummy = *((volatile unsigned int *)(0xA0000000 | (0x33 << 11)));
> >
> > many strange things can occur.
> >
> > The value depends on the geometry of your SDRAM and is rather difficult
> > to calculate. Search for answers of Rolf Meeser, he's the guy who
helped
> > me and others out of this weird issue.
> >
> > Herbert
> >
> > Nico Bollen schrieb:
> > > --- In l..., "Nico Bollen" wrote:
> > >
> > >> --- In l..., "ljaschko" wrote:
> > >>
> > >>> Hi Nico,
> > >>>
> > >>>
> > >>>> does anybody have correct initialisation and writing code examples
>where I could take a look at?
> > >>>> Many thanks in advance.
> > >>>>
> > >>> My usual advice in such case:
> > >>> - take a look on Olimex SDRAM initialization on their site.
> > >>>
> > >>> Regards
> > >>> Vladimir
> > >>>
> > >>>
> > >> Hi Vladimir,
> > >>
> > >> Thanks for your reply.
> > >> I've tried to change all settings to the Olimex settings but
I've still got the same problem... of course I did not change the Mode
register because I'm using another RAM chip. Maybe I'm making a
mistake over there?..
> > >>
> > >> Regards,
> > >> Nico
> > >>
> > >>
> > >
> > > Dear all,
> > >
> > > Seems that the RAM is working but I'm only able to write maximum
60bytes to it at the same time, afterwards I have to wait several seconds before
writing the next 60bytes.
> > > The RAM content is cleared (0xFFFF) when enabling the LCD controller
module...
> > > Any ideas?
> > > Many thanks.
> > >
> > > Regards,
> > > Nico
> > >
> > >
> >
> > --
> >
> > demmel products
> > Radnitzkygasse 43
> > A-1100 Vienna / Austria / Europe
> > Voice: +43-1-6894700-0
> > Fax: +43-1-6894700-40
> > Email: dh@
> > WWW: http://www.demmel.com
> >
> >
> >
>
I've read those postings.
It's very difficult to find the correct value but I think I have followed
all rules...
In the meanwhile I also tried 0x33<<10 and 0x33<<12, with both combinations the
behaviour was the same.
Thanks
Nico
--- In l..., Herbert Demmel wrote: >
> Nico,
>
> did you have a look to earlier postings about SRAM in this group ?
>
> If you have a wrong value in
>
> dummy = *((volatile unsigned int *)(0xA0000000 | (0x33 << 11)));
>
> many strange things can occur.
>
> The value depends on the geometry of your SDRAM and is rather difficult
> to calculate. Search for answers of Rolf Meeser, he's the guy who helped
> me and others out of this weird issue.
>
> Herbert
>
> Nico Bollen schrieb:
> > --- In l..., "Nico Bollen" wrote:
> >
> >> --- In l..., "ljaschko" wrote:
> >>
> >>> Hi Nico,
> >>>
> >>>
> >>>> does anybody have correct initialisation and writing code examples >where
I could take a look at?
> >>>> Many thanks in advance.
> >>>>
> >>> My usual advice in such case:
> >>> - take a look on Olimex SDRAM initialization on their site.
> >>>
> >>> Regards
> >>> Vladimir
> >>>
> >>>
> >> Hi Vladimir,
> >>
> >> Thanks for your reply.
> >> I've tried to change all settings to the Olimex settings but I've
still got the same problem... of course I did not change the Mode register
because I'm using another RAM chip. Maybe I'm making a mistake over
there?..
> >>
> >> Regards,
> >> Nico
> >>
> >>
> >
> > Dear all,
> >
> > Seems that the RAM is working but I'm only able to write maximum
60bytes to it at the same time, afterwards I have to wait several seconds before
writing the next 60bytes.
> > The RAM content is cleared (0xFFFF) when enabling the LCD controller
module...
> > Any ideas?
> > Many thanks.
> >
> > Regards,
> > Nico
> >
> >
>
> --
>
> demmel products
> Radnitzkygasse 43
> A-1100 Vienna / Austria / Europe
> Voice: +43-1-6894700-0
> Fax: +43-1-6894700-40
> Email: dh@...
> WWW: http://www.demmel.com
>
>
Reply by Herbert Demmel●May 27, 20092009-05-27
Nico,
did you have a look to earlier postings about SRAM in this group ?
If you have a wrong value in
dummy = *((volatile unsigned int *)(0xA0000000 | (0x33 << 11)));
many strange things can occur.
The value depends on the geometry of your SDRAM and is rather difficult
to calculate. Search for answers of Rolf Meeser, he's the guy who helped
me and others out of this weird issue.
Herbert
Nico Bollen schrieb: > --- In l..., "Nico Bollen" wrote:
>
>> --- In l..., "ljaschko" wrote:
>>
>>> Hi Nico,
>>>
>>>
>>>> does anybody have correct initialisation and writing code examples >where I
could take a look at?
>>>> Many thanks in advance.
>>>>
>>> My usual advice in such case:
>>> - take a look on Olimex SDRAM initialization on their site.
>>>
>>> Regards
>>> Vladimir
>>>
>>>
>> Hi Vladimir,
>>
>> Thanks for your reply.
>> I've tried to change all settings to the Olimex settings but I've
still got the same problem... of course I did not change the Mode register
because I'm using another RAM chip. Maybe I'm making a mistake over
there?..
>>
>> Regards,
>> Nico
>>
>>
>
> Dear all,
>
> Seems that the RAM is working but I'm only able to write maximum 60bytes
to it at the same time, afterwards I have to wait several seconds before writing
the next 60bytes.
> The RAM content is cleared (0xFFFF) when enabling the LCD controller
module...
> Any ideas?
> Many thanks.
>
> Regards,
> Nico
>
>
--
demmel products
Radnitzkygasse 43
A-1100 Vienna / Austria / Europe
Voice: +43-1-6894700-0
Fax: +43-1-6894700-40
Email: d...@demmel.com
WWW: http://www.demmel.com
Reply by Nico Bollen●May 26, 20092009-05-26
--- In l..., "Nico Bollen" wrote: >
> --- In l..., "ljaschko" wrote:
> >
> > Hi Nico,
> >
> > > does anybody have correct initialisation and writing code examples >where
I could take a look at?
> > > Many thanks in advance.
> >
> > My usual advice in such case:
> > - take a look on Olimex SDRAM initialization on their site.
> >
> > Regards
> > Vladimir
> > Hi Vladimir,
>
> Thanks for your reply.
> I've tried to change all settings to the Olimex settings but I've
still got the same problem... of course I did not change the Mode register
because I'm using another RAM chip. Maybe I'm making a mistake over
there?..
>
> Regards,
> Nico
>
Dear all,
Seems that the RAM is working but I'm only able to write maximum 60bytes to
it at the same time, afterwards I have to wait several seconds before writing
the next 60bytes.
The RAM content is cleared (0xFFFF) when enabling the LCD controller
module...
Any ideas?
Many thanks.
Regards,
Nico
Reply by Nico Bollen●May 26, 20092009-05-26
--- In l..., "ljaschko" wrote: >
> Hi Nico,
>
> > does anybody have correct initialisation and writing code examples >where I
could take a look at?
> > Many thanks in advance.
>
> My usual advice in such case:
> - take a look on Olimex SDRAM initialization on their site.
>
> Regards
> Vladimir
>
Hi Vladimir,
Thanks for your reply.
I've tried to change all settings to the Olimex settings but I've
still got the same problem... of course I did not change the Mode register
because I'm using another RAM chip. Maybe I'm making a mistake over
there?..
Regards,
Nico
Reply by ljaschko●May 26, 20092009-05-26
Hi Nico,
> does anybody have correct initialisation and writing
code examples >where I could take a look at?
> Many thanks in advance.
My usual advice in such case:
- take a look on Olimex SDRAM initialization on their site.
Regards
Vladimir
Reply by Nico Bollen●May 26, 20092009-05-26
Dear all,
I have an sdram device (MT48LC4M16A2P) connected as follows:
But the data is never writen :-s
I've bin looking at this for a long time now and I don't have a
solution yet therefore my request to you all.
Does anybody have an idea what I could be doing wrong, does anybody have correct
initialisation and writing code examples where I could take a look at?
Many thanks in advance.