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Beginner question about slice and LUT

 
 
Giox
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      02-22-2007
Hello everybody,
where can I find a clear explanation of the difference between

Number of Slice Flip Flops

and

Number of 4 input LUT

in the feedback provided by ISE Xilinx.
I'm a bit confused.
Any explanation or link will be very helpful
Gio

 
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weber
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      02-22-2007
On 22 fev, 13:34, "Giox" <(E-Mail Removed)> wrote:
> Hello everybody,
> where can I find a clear explanation of the difference between
>
> Number of Slice Flip Flops
>
> and
>
> Number of 4 input LUT
>
> in the feedback provided by ISE Xilinx.
> I'm a bit confused.
> Any explanation or link will be very helpful
> Gio


I guess that relation can be different for each FPGA (Xilinx: Spartan,
Virtex 2, Virtex 4 etc) so a good place to find this information would
be the user guide of your target board.
Cheers,
weber

 
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Andrew FPGA
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      02-23-2007
> where can I find a clear explanation of the difference between

Look in the datasheet for the device (Spartan3, virtex4, ...etc) you
are using.
i.e http://www.xilinx.com/xlnx/xweb/xil_...y=Publications



 
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Martin Thompson
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      02-23-2007
"Giox" <(E-Mail Removed)> writes:

> Hello everybody,
> where can I find a clear explanation of the difference between
>


The difference between them is that they are a count of completely
different things...

> Number of Slice Flip Flops
>


The is the number of flipflops used up by your design, that have been
put into the slices. Flipflops in IO blocks don't count towards this number

> and
>
> Number of 4 input LUT
>


This is the number of LUTs used up by your design. These are also in
the slices.

> in the feedback provided by ISE Xilinx.
> I'm a bit confused.


What by? I wonder if you are making things more complicated than they
actually are?

> Any explanation or link will be very helpful
> Gio
>


I'm happy to explain more if desired

Cheers,
Martin

--
http://www.velocityreviews.com/forums/(E-Mail Removed)
TRW Conekt - Consultancy in Engineering, Knowledge and Technology
http://www.conekt.net/electronics.html
 
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Giox
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      02-26-2007
Thanks a lot for your help.
You solved my doubts.
Giox

On 23 Feb, 15:33, Martin Thompson <(E-Mail Removed)> wrote:
> "Giox" <(E-Mail Removed)> writes:
> > Hello everybody,
> > where can I find a clear explanation of the difference between

>
> The difference between them is that they are a count of completely
> different things...
>
> > Number of Slice Flip Flops

>
> The is the number of flipflops used up by your design, that have been
> put into the slices. Flipflops in IO blocks don't count towards this number
>
> > and

>
> > Number of 4 input LUT

>
> This is the number of LUTs used up by your design. These are also in
> the slices.
>
> > in the feedback provided by ISE Xilinx.
> > I'm a bit confused.

>
> What by? I wonder if you are making things more complicated than they
> actually are?
>
> > Any explanation or link will be very helpful
> > Gio

>
> I'm happy to explain more if desired
>
> Cheers,
> Martin
>
> --
> (E-Mail Removed)
> TRW Conekt - Consultancy in Engineering, Knowledge and Technologyhttp://www.conekt.net/electronics.html



 
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Martin Thompson
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      02-27-2007
"Giox" <(E-Mail Removed)> writes:

> Thanks a lot for your help.
> You solved my doubts.
> Giox


You're welcome!

Cheers,
Martin

--
(E-Mail Removed)
TRW Conekt - Consultancy in Engineering, Knowledge and Technology
http://www.conekt.net/electronics.html
 
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