AT91sam9263 running at 800*600 full screen

Hi,

Want to port a full screen (800x600 or 1024*768) LCD application onto an 
AT91sam9263 system running ARM Linux. The Atmel kit I am playing around with 
has a QVGA interface. The data sheet is a little vague as to the capability 
of its internal LCD controller. Any advice or comment would be much 
appreciated.

TLH 

"Tat Ho" <tatleungho@gmail.com> skrev i meddelandet 
news:fcld1m$ek5$1@nnews.pacific.net.hk...
> Hi,
>
> Want to port a full screen (800x600 or 1024*768) LCD application onto an 
> AT91sam9263 system running ARM Linux. The Atmel kit I am playing around 
> with has a QVGA interface. The data sheet is a little vague as to the 
> capability of its internal LCD controller. Any advice or comment would be 
> much appreciated.
>
> TLH

The LCD controller does not have a problem with large resolutions.
It can handle 4k x 4k.

The most important thing is how much bandwidth you need from your memory.

With 800 x 600 x 16bpp * 60 Hz you need 56,25 MB/s for display refresh

With 1024 x 768 x 16 bpp * 60 Hz you need 92,16 MB/s for display refresh

The CPU, running at 200 MHz has 400 MB/s max bandwidth to memory.
There is overhead to be considered, so in practice it will be less than 
that.

If you put the display buffer on EBI0, you will lose minimum 20-35% of the 
CPU
performance.

A good approach is to calculate the display contents on EBI0,
and then let the DMA controller copy the frame to EBI1 which
will only be used to refresh the display.

-- 
Best Regards,
Ulf Samuelsson
This is intended to be my personal opinion which may,
or may not be shared by my employer Atmel Nordic AB

"Ulf Samuelsson" <ulf@a-t-m-e-l.com> wrote in message 
news:fcnrkc$rp6$4@aioe.org...
> "Tat Ho" <tatleungho@gmail.com> skrev i meddelandet 
> news:fcld1m$ek5$1@nnews.pacific.net.hk...
>> Hi,
>>
>> Want to port a full screen (800x600 or 1024*768) LCD application onto an 
>> AT91sam9263 system running ARM Linux. The Atmel kit I am playing around 
>> with has a QVGA interface. The data sheet is a little vague as to the 
>> capability of its internal LCD controller. Any advice or comment would be 
>> much appreciated.
>>
>> TLH
>
> The LCD controller does not have a problem with large resolutions.
> It can handle 4k x 4k.
>
> The most important thing is how much bandwidth you need from your memory.
>
> With 800 x 600 x 16bpp * 60 Hz you need 56,25 MB/s for display refresh
>
> With 1024 x 768 x 16 bpp * 60 Hz you need 92,16 MB/s for display refresh
>
> The CPU, running at 200 MHz has 400 MB/s max bandwidth to memory.
> There is overhead to be considered, so in practice it will be less than 
> that.
>
> If you put the display buffer on EBI0, you will lose minimum 20-35% of the 
> CPU
> performance.
>
> A good approach is to calculate the display contents on EBI0,
> and then let the DMA controller copy the frame to EBI1 which
> will only be used to refresh the display.
>
> -- 
> Best Regards,
> Ulf Samuelsson
> This is intended to be my personal opinion which may,
> or may not be shared by my employer Atmel Nordic AB
>
>

Ulf,

Thanks for the clarification and advice.

Best regards,

TLH