At 15:16 25.11.2008 +0100, you wrote:
>Looks good.
>
>Just one final question. I was reading LPC2478UM for configuration, but
>not very deeply at the moment.

You *should* do that ...

>Here's my situation: my panel has 3x8bits
>RGB interface, the external SRAM will be 8-bit and I would like to use
>8bpp via pallete. Is this possible, or I need 32bit wide external memory?

The bus-width of your SRAM has nothing to do with the number of bits
you use for the LCD. Otherwise you would not be able to store e.g.
word or integer data into the SRAM ...

Herbert

An Engineer's Guide to the LPC2100 Series

Looks good.

Just one final question. I was reading LPC2478UM for configuration, but
not very deeply at the moment. Here's my situation: my panel has 3x8bits
RGB interface, the external SRAM will be 8-bit and I would like to use
8bpp via pallete. Is this possible, or I need 32bit wide external memory?

Marko

Herbert Demmel pravi:
> At 11:36 25.11.2008 +0100, you wrote:
>
>> Thanks!
>>
>> I calculated and got about 15% load with 8 bit SRAM. Is this crytical?
>>
>
> No, not really. If you do not want to have a lot of other traffic via
> the external bus, it's rather peanuts. Note, that when executing from
> the internal flash and reading/writing the internal RAM no speed
> decrease will happen due to the frame buffer refresh.
>
> Herbert
>
>
>> Marko
>>
>> Herbert Demmel pravi:
>>
>>> At 10:39 25.11.2008 +0100, you wrote:
>>>
>>>
>>>> Hi!
>>>>
>>>> Is it possible to use external 8-bit SRAM for frame buffer for LCD with
>>>> LPC2478?
>>>>
>>>>
>>> Yes, you can even use the internal RAM if the size is enough for your
>>> display. There is a bandwidth calculator on the NXP website showing
>>> how much traffic one can expect on the bus for the display refresh.
>>>
>>> Herbert
>>>
>>>
>>>

At 11:36 25.11.2008 +0100, you wrote:
>Thanks!
>
>I calculated and got about 15% load with 8 bit SRAM. Is this crytical?

No, not really. If you do not want to have a lot of other traffic via
the external bus, it's rather peanuts. Note, that when executing from
the internal flash and reading/writing the internal RAM no speed
decrease will happen due to the frame buffer refresh.

Herbert

>Marko
>
>Herbert Demmel pravi:
> > At 10:39 25.11.2008 +0100, you wrote:
> >
> >> Hi!
> >>
> >> Is it possible to use external 8-bit SRAM for frame buffer for LCD with
> >> LPC2478?
> >>
> >
> > Yes, you can even use the internal RAM if the size is enough for your
> > display. There is a bandwidth calculator on the NXP website showing
> > how much traffic one can expect on the bus for the display refresh.
> >
> > Herbert
> >
> >
>

Thanks!

I calculated and got about 15% load with 8 bit SRAM. Is this crytical?

Marko

Herbert Demmel pravi:
> At 10:39 25.11.2008 +0100, you wrote:
>
>> Hi!
>>
>> Is it possible to use external 8-bit SRAM for frame buffer for LCD with
>> LPC2478?
>>
>
> Yes, you can even use the internal RAM if the size is enough for your
> display. There is a bandwidth calculator on the NXP website showing
> how much traffic one can expect on the bus for the display refresh.
>
> Herbert
>
>

At 10:39 25.11.2008 +0100, you wrote:
>Hi!
>
>Is it possible to use external 8-bit SRAM for frame buffer for LCD with
>LPC2478?

Yes, you can even use the internal RAM if the size is enough for your
display. There is a bandwidth calculator on the NXP website showing
how much traffic one can expect on the bus for the display refresh.

Herbert

>M.
>
>