Battle of the Vapours

[Thomas Womack]

OK, the next-generation parts at both application grades from both
manufacturers are now announced. I've not been around for long enough
to know how long to expect between announcement and availability at
the hobbyist level; is Christmas 2005 for Cyclone II (announced today)
dev boards reasonable?

It's nice to see reasonably serious levels of DSP appearing at the
low-end parts, though I'm a little disappointed that we're not seeing
seas of floating-point units in the high end, even in the Virtex 4SX;
those can be so much smaller as macrocells than built out of logic.

What _is_ the business about "maximum toggle frequency 500MHz (for
export control)" in the Spartan3 datasheet?

I was contemplating real-time fractal generators, and it's not clear
that a 4+50 x 4+50 -> 4+50 fixed-point triple-precision multiplier
built in a Spartan 3 would be price-competitive with small piles of
PCs; rough summing of propagation delays suggest you can get three,
with 10-15ns propagation, into an XC3S1000. Which is 200-300Mflops,
and with small-volume costs and board-building charges I don't see I
could get the price below the $100 required to compete on
price/performance with Athlon64.

Whatever happens, these will be wonderful things to play with; many
thanks to everybody involved in bringing on the Era of Programmable
Hardware!

Tom

 

[Peter Alfke]

From: Thomas Womack <twomack@chiark.greenend.org.uk
Organization: Linux Unlimited
Newsgroups: comp.arch.fpga
Date: 28 Jun 2004 20:03:20 +0100 (BST)
Subject: Battle of the Vapours

What _is_ the business about "maximum toggle frequency 500MHz (for
export control)" in the Spartan3 datasheet?

There are restrictions on exporting (from the US) devices above a certain

level of sophistication. And the government measures that as toggle rate.
(The idea was to avoid helping the "evil empire" develop better missile
guidance systems).
The Cold War lives forever...
Peter Alfke

 

[Jim Granville]

Thomas Womack wrote:

OK, the next-generation parts at both application grades from both
manufacturers are now announced. I've not been around for long enough
to know how long to expect between announcement and availability at
the hobbyist level; is Christmas 2005 for Cyclone II (announced today)
dev boards reasonable?

Probably, as Altera mention Q2 2005 for samples of most devices.

Lattice also have a new family, with their prices quoted at 1K
( compared with the others of 18 months out, and asymptope volumes
Lattice also say first samples in July 2004, (yes, next month, not
next year...)

It's nice to see reasonably serious levels of DSP appearing at the
low-end parts, though I'm a little disappointed that we're not seeing
seas of floating-point units in the high end, even in the Virtex 4SX;
those can be so much smaller as macrocells than built out of logic.

What _is_ the business about "maximum toggle frequency 500MHz (for
export control)" in the Spartan3 datasheet?

I was contemplating real-time fractal generators, and it's not clear
that a 4+50 x 4+50 -> 4+50 fixed-point triple-precision multiplier
built in a Spartan 3 would be price-competitive with small piles of
PCs; rough summing of propagation delays suggest you can get three,
with 10-15ns propagation, into an XC3S1000. Which is 200-300Mflops,
and with small-volume costs and board-building charges I don't see I
could get the price below the $100 required to compete on
price/performance with Athlon64.

AMD has announced a lower cost MPU, still no word on Price/Bits, but it
will be real well in advance of the vapor-FPGAs.
Hard to imagine it not being 64bit, given the [marketing
advantage/silicon cost] ratios...
-jg

 

[Thomas Womack]

In article <BD05CC88.7201%peter@xilinx.com>,
Peter Alfke <peter@xilinx.com> wrote:

From: Thomas Womack <twomack@chiark.greenend.org.uk
Organization: Linux Unlimited
Newsgroups: comp.arch.fpga
Date: 28 Jun 2004 20:03:20 +0100 (BST)
Subject: Battle of the Vapours

What _is_ the business about "maximum toggle frequency 500MHz (for
export control)" in the Spartan3 datasheet?

There are restrictions on exporting (from the US) devices above a certain
level of sophistication. And the government measures that as toggle rate.
(The idea was to avoid helping the "evil empire" develop better missile
guidance systems).

OK, I suppose that makes a certain degree of sense; I wonder slightly
how the big microprocessor vendors get round that issue. There were
those Apple adverts saying that their machine was by export-control
standards a supercomputer, but I've seen plenty of dual-G5 boxes on
my side of the Atlantic.

With my Dr Evil hat on, I wonder slightly how you set a maximum toggle
frequency when the LUT propagation time is already down to 700ps or so
-- I wonder if it's a matter of refraining from heroic engineering
efforts to keep parasitic capacitance down in the flip-flops, or a
couple of lines in the depths of the hardware-compiler?

Tom

 

[Peter Alfke]

From: Thomas Womack <twomack@chiark.greenend.org.uk
Well, the US does not consider the UK an "evil empire" (at least not since

the war of 1815), so the export rules vary by country. Last I looked many
years ago, Albania was at the bottom of the list...

Regarding max toggle rate, LUT and clock-to-Q are just one ingredient,
routing is the bigger one. Present routing structures favor complex designs,
but hurt very simple situations, like toggling flip-flops.

Peter Alfke

(The idea was to avoid helping the "evil empire" develop better missile
guidance systems).

OK, I suppose that makes a certain degree of sense; I wonder slightly
how the big microprocessor vendors get round that issue. There were
those Apple adverts saying that their machine was by export-control
standards a supercomputer, but I've seen plenty of dual-G5 boxes on
my side of the Atlantic.

With my Dr Evil hat on, I wonder slightly how you set a maximum toggle
frequency when the LUT propagation time is already down to 700ps or so
-- I wonder if it's a matter of refraining from heroic engineering
efforts to keep parasitic capacitance down in the flip-flops, or a
couple of lines in the depths of the hardware-compiler?

Tom

 

[Symon]

Tom,
I think you're getting the wrong end of the stick. Xilinx make their parts
go as fast as they want. They then have to publish an FTOG figure which the
US government then uses to decide if the chips should be restricted, and if
so, to which countries. Presumably you're British, so (according to the
export rules!) not part of the 'axis of evil'. You'll get the parts OK, but
don't build them into something you're planning on selling in North Korea.
Or there'll be ....trouble...
Cheers mate, Syms.
p.s. Google for microprocessors "export restrictions"


"Thomas Womack" <twomack@chiark.greenend.org.uk> wrote in message
news:jwj*wscoq@news.chiark.greenend.org.uk...

With my Dr Evil hat on, I wonder slightly how you set a maximum toggle
frequency when the LUT propagation time is already down to 700ps or so
-- I wonder if it's a matter of refraining from heroic engineering
efforts to keep parasitic capacitance down in the flip-flops, or a
couple of lines in the depths of the hardware-compiler?

Tom

 

[rickman]

Peter Alfke wrote:

From: Thomas Womack <twomack@chiark.greenend.org.uk
Organization: Linux Unlimited
Newsgroups: comp.arch.fpga
Date: 28 Jun 2004 20:03:20 +0100 (BST)
Subject: Battle of the Vapours

What _is_ the business about "maximum toggle frequency 500MHz (for
export control)" in the Spartan3 datasheet?

There are restrictions on exporting (from the US) devices above a certain
level of sophistication. And the government measures that as toggle rate.
(The idea was to avoid helping the "evil empire" develop better missile
guidance systems).
The Cold War lives forever...

So are products containing Spartan 3 parts at 500 MHz toggle freq
restricted? I have looked at several government web sites and not been
able to determine what is restricted and what is not.

--

Rick "rickman" Collins

rick.collins@XYarius.com
Ignore the reply address. To email me use the above address with the XY
removed.

Arius - A Signal Processing Solutions Company
Specializing in DSP and FPGA design URL http://www.arius.com
4 King Ave 301-682-7772 Voice
Frederick, MD 21701-3110 301-682-7666 FAX

 

[rickman]

Thomas Womack wrote:

In article <BD05CC88.7201%peter@xilinx.com>,
Peter Alfke <peter@xilinx.com> wrote:


From: Thomas Womack <twomack@chiark.greenend.org.uk
Organization: Linux Unlimited
Newsgroups: comp.arch.fpga
Date: 28 Jun 2004 20:03:20 +0100 (BST)
Subject: Battle of the Vapours

What _is_ the business about "maximum toggle frequency 500MHz (for
export control)" in the Spartan3 datasheet?

There are restrictions on exporting (from the US) devices above a certain
level of sophistication. And the government measures that as toggle rate.
(The idea was to avoid helping the "evil empire" develop better missile
guidance systems).

OK, I suppose that makes a certain degree of sense; I wonder slightly
how the big microprocessor vendors get round that issue. There were
those Apple adverts saying that their machine was by export-control
standards a supercomputer, but I've seen plenty of dual-G5 boxes on
my side of the Atlantic.

The restrictions can be very strange. I was involved in a converstion
about GSM cell phone manufacturing and repair once. Seems the
encryption in the GSM phones was "export controlled" by the US. So the
phones could be made outside the US and shipped in. But they could not
be shipped back out for repair.

--

Rick "rickman" Collins

rick.collins@XYarius.com
Ignore the reply address. To email me use the above address with the XY
removed.

Arius - A Signal Processing Solutions Company
Specializing in DSP and FPGA design URL http://www.arius.com
4 King Ave 301-682-7772 Voice
Frederick, MD 21701-3110 301-682-7666 FAX

 

[Jim Granville]

Peter Alfke wrote:

From: Thomas Womack <twomack@chiark.greenend.org.uk
What _is_ the business about "maximum toggle frequency 500MHz (for
export control)" in the Spartan3 datasheet?


There are restrictions on exporting (from the US) devices above a certain
level of sophistication. And the government measures that as toggle rate.
(The idea was to avoid helping the "evil empire" develop better missile
guidance systems).
The Cold War lives forever...
Peter Alfke

The politicians, of course, have no idea what any of this means.
I can picture them looking at the specs...:
Toggle rates of 500MHz, yes, that's fast.....
3.3GBps - hmm, no 3.3 is less than 500, so that's OK
10Gbps - still OK, 10 is < 500
2.4 terabit - whoa, someone could build a tera-network using that!!

 

[Austin Lesea]

Jim,

You are absolutely correct: we must prevent tera.

There is a war on tera, right now!

Austin

PS: I've herad of 'two bit' networks, but tera-bit networks???

Jim Granville wrote:

Peter Alfke wrote:


From: Thomas Womack <twomack@chiark.greenend.org.uk

What _is_ the business about "maximum toggle frequency 500MHz (for

export control)" in the Spartan3 datasheet?


There are restrictions on exporting (from the US) devices above a certain
level of sophistication. And the government measures that as toggle rate.
(The idea was to avoid helping the "evil empire" develop better missile
guidance systems).
The Cold War lives forever...
Peter Alfke


The politicians, of course, have no idea what any of this means.
I can picture them looking at the specs...:
Toggle rates of 500MHz, yes, that's fast.....
3.3GBps - hmm, no 3.3 is less than 500, so that's OK
10Gbps - still OK, 10 is < 500
2.4 terabit - whoa, someone could build a tera-network using that!!