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Xilinx/Altera gate equivalence

Started by dudesinmexico July 16, 2008
Are there any rules of thumb to figure out the equivalent number of
logic resources
needed to implement the same design on Stratix IV vs., say,
Virtex-4/5?
I am thinking of random logic, i.e. a CLB vs. LAB conversion factor...

Thanks!
dudesinmexico wrote:
> Are there any rules of thumb to figure out the equivalent number of > logic resources > needed to implement the same design on Stratix IV vs., say, > Virtex-4/5? > I am thinking of random logic, i.e. a CLB vs. LAB conversion factor...
Quartus will give the exact utilization and pick a device for you, if you have source code. -- Mike Treseler
On Jul 16, 11:57=A0am, Mike Treseler <mike_trese...@comcast.net> wrote:
> dudesinmexico wrote: > > Are there any rules of thumb to figure out the equivalent number of > > logic resources > > needed to implement the same design on Stratix IV vs., say, > > Virtex-4/5? > > I am thinking of random logic, i.e. a CLB vs. LAB conversion factor... > > Quartus will give the exact utilization > and pick a device for you, if you have source code. >
I don't, and that's why I am asking... I have a Virtex-4 design and I'd like to find what Stratix IV part it will fit in. dudesinmexico
dudes,

If you contact your Xilinx FAE I am sure they would be happy to help you.

If this is an academic study, then I suggest you will have to get
somewhere from one to five hundred designs, and then target them to each
architecture, and then examine the results, and try to draw some
conclusions.

Of course, whatever designs you choose will be challenged as being the
'wrong' ones, or ones that are 'obviously biased.'

Personally, I believe market forces are at work so that the cost of
doing whatever you want to do is roughly equal between the two choices.

Then it becomes a question of component availability, lowest power, or
fastest speed, or best IP libraries, or best support.

Or, a question of all of the above.

Austin
dudesinmexico wrote:

> I don't, and that's why I am asking... I have a Virtex-4 design and > I'd like to find what Stratix IV > part it will fit in.
I agree with Austin. Pricing is roughly equivalent because of competition. There is no better estimate without a redesign. Porting a design without source code sounds painful to me. I would leave it alone if cost is the only reason for change. -- Mike Treseler
On Jul 16, 3:15=A0pm, austin <aus...@xilinx.com> wrote:
> dudes, > > If you contact your Xilinx FAE I am sure they would be happy to help you. >
So these days Xilinx FAEs help their customers to port their designs to Altera? Sorry Austin, I could not resist.. ;) Anyway, this is not an academic exercise. Porting a very complex Virtex4 design to Stratix is not something that one can do in a few days, so I was looking for ballpark estimates about the equivalence between Xilinx and Altera "gates".
> If this is an academic study, then I suggest you will have to get > somewhere from one to five hundred designs, and then target them to each > architecture, and then examine the results, and try to draw some > conclusions. > > Of course, whatever designs you choose will be challenged as being the > 'wrong' ones, or ones that are 'obviously biased.' > > Personally, I believe market forces are at work so that the cost of > doing whatever you want to do is roughly equal between the two choices. > > Then it becomes a question of component availability, lowest power, or > fastest speed, or best IP libraries, or best support. > > Or, a question of all of the above. > > Austin
>Anyway, this is not an academic exercise. Porting a very complex >Virtex4 design >to Stratix is not something that one can do in a few days, so I was >looking >for ballpark estimates about the equivalence between Xilinx and Altera >"gates".
Have you looked at the Stratix data sheet? Did you find anything close to a CLB/FF pair? If so, assume they are 1:1. Then count the special things you use: BRAMs, clock buffers, multipliers and whatevber. Then see if Altera has something similar. -- These are my opinions, not necessarily my employer's. I hate spam.
On 17 jul, 05:00, hal-use...@ip-64-139-1-69.sjc.megapath.net (Hal
Murray) wrote:
> >Anyway, this is not an academic exercise. Porting a very complex > >Virtex4 design > >to Stratix is not something that one can do in a few days, so I was > >looking > >for ballpark estimates about the equivalence between Xilinx and Altera > >"gates". > > Have you looked at the Stratix data sheet? =A0Did you find anything > close to a CLB/FF pair? =A0If so, assume they are 1:1. > > Then count the special things you use: BRAMs, clock buffers, multipliers > and whatevber. =A0Then see if Altera has something similar. > > -- > These are my opinions, not necessarily my employer's. =A0I hate spam.
Hi, I have searched before about the comparison Logic Elements and Logic Cells. Most of the result say LE =3D LC, but once (@ Altera website) I found that LE =3D 1.125*LC Bye Bert
"dudesinmexico" <dudesinmexico@gmail.com> wrote in message 
news:2e6bf67c-1107-4af3-8452-6b7598a4bf98@25g2000hsx.googlegroups.com...
On Jul 16, 11:57 am, Mike Treseler <mike_trese...@comcast.net> wrote:
> dudesinmexico wrote: > > Are there any rules of thumb to figure out the equivalent number of > > logic resources > > needed to implement the same design on Stratix IV vs., say, > > Virtex-4/5? > > I am thinking of random logic, i.e. a CLB vs. LAB conversion factor... > > Quartus will give the exact utilization > and pick a device for you, if you have source code. > > >I don't, and that's why I am asking... I have a Virtex-4 design and >I'd like to find what Stratix IV >part it will fit in. > > dudesinmexico
1) Get an evaluation license for Precision/Synplicity 2) Download a number of large free design from the web 3) Synthesize for Virtex4/Stratix4 4) P&R the designs, compare Area/Delay IMHO there is very little point in comparing large FPGA's from an architectural point of view without including the Synthesis/P&R factor. Hans www.ht-lab.com
Bert wrote:
> On 17 jul, 05:00, hal-use...@ip-64-139-1-69.sjc.megapath.net (Hal > Murray) wrote: >>> Anyway, this is not an academic exercise. Porting a very complex >>> Virtex4 design >>> to Stratix is not something that one can do in a few days, so I was >>> looking >>> for ballpark estimates about the equivalence between Xilinx and Altera >>> "gates". >> Have you looked at the Stratix data sheet? Did you find anything >> close to a CLB/FF pair? If so, assume they are 1:1. >> >> Then count the special things you use: BRAMs, clock buffers, multipliers >> and whatevber. Then see if Altera has something similar. >> >> -- >> These are my opinions, not necessarily my employer's. I hate spam. > > Hi, > > I have searched before about the comparison Logic Elements and Logic > Cells. Most of the result say LE = LC, but once (@ Altera website) I > found that LE = 1.125*LC > > Bye > Bert
This highly depends on the actual design, there are some minor differences between LEs and LCs that might or might not have an advantage for certain designs. Nevertheless estimating 1:1 is a fairly good choice in my opinion. At least as long as you do not want to go without any reserve of LEs/LCs. Regards, Lorenz