Xilinx Slice and Altera ...?

Not necessarily.  The RTL coding can strongly bias a designs suitability to a
particular architecture.  This situation has improved slightly in the latest
generations because the architructures are starting to look more like one
another, but still the architecture of your design heavily influences how
that design maps into the underlying FPGA architecture.  A not so obvious
example concerns arithmetic.  The altera structure reduces the logic to 2
input arithmetic with an added add/subtract control where the Xilinx
architecture leaves you with a 4 input arithmetic function, making it treat
things like mux-add functions a bit differently.

Mike Treseler wrote:

> rickman wrote:
>
> > You can analyze the differences on paper all day, and you still won't
> > know how your design will do in either family of parts.  The best thing
> > to do is to write your HDL to be generic and see how it fits.
>
> Well said.
>
> Working generic synth code cuts through
> technobabble like a knife. It tests
> the tools and the device from front to back
> and provides utilization and fmax benchmarks
> that you just can't get any other way.
>
> That said, I have noticed that Altera's
> ep1s series is much more Xilinx-like than
> ep20k.
>
>    -- Mike Treseler

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--Ray Andraka, P.E.
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