XC4k parts obsolete ?

Is the discontinue notice for somw parts that had extremely low volumes.

Aust> This is a Question to Xilinx experts.

Thanks Austin. The "port" won't be too difficult anyway :-)

Bert

BTW, Atmel AT40K are claimed to be pin-compatible to xilinx XC4K, but if you can redesign to recent lowcost FPGA then thats possible preferable.

antti

Pin compatible only in that the pin definitions matched so that you could concievably put an equivalent design (different bit stream) in the Atmel part and use it in a xilinx socket. That is where the similarities ended. The AT40K has a completely different internal architecture, and most notably does not have any fast carry logic, and instead of using LUTs for memory have small 32 bit memories for every couple of logic cells. If you compare architectures, you'll find that many Xilinx designs will not fit in the resources supplied in the "equivalent" Atmel part.

--
--Ray Andraka, P.E.
President, the Andraka Consulting Group, Inc.
401/884-7930     Fax 401/884-7950
email ray@andraka.com  
http://www.andraka.com  

 "They that give up essential liberty to obtain a little 
  temporary safety deserve neither liberty nor safety."
                                          -Benjamin Franklin, 1759

Hi Ray,

yes sure I forgot to mention those details.. its totally different thing internally. I was just looking at AT94 and AT40 in order to see if I could maybe have an application for them, the AT94S10 is $19, its true single chip, has onchip

25 MIPS RISC and can do dynamic reconfiguration. could be used as replacement (way more flexible) for SystemACE, that where my interest was. I still have the very secret document about all the bitstream cell bit info of the AT40K so still having ideas doing something that really benefits from dynamic reconfiguration.

Antti

"Ray Andraka" schrieb im Newsbeitrag news:poTbe.50$c83.49@lakeread07...

Thanks for the follow-up.

One of the "valid" reasons I didn't give details about was that these chips are running at an ambient temperature of 175 degrees Celsius :-) This customer won't qualify a new family every now and then as you can surely guess ;-)

Any semi wiling to qualify the latest chips at this temp ?

I got one of those around here somewhere too. The AT40K is getting kinda long in the tooth though. The only advantage it has over the Virtex parts is the fact that you can partially reconfigure down to the cell level, where Virtex requires you to reconfig a whole column (or a a whole column segment for V4). Regardless, the tools for partial config have never really been developed far enough to make it much more than a lab curiousity. I did make some forays into partial configuration years ago, and it was painful. As far as I've been able to determine, the design described in my dynamic video pipeline processor paper (on the website) is the first application that attempted to do partial configuration with the clock running. All the designs described in the prior literature suspended the clock while reconfiguring. Running the clock opened a whole new can of worms, and the Atmel architecture was not well suited for it because you had to be careful what order you removed and replaced wires to avoid damaging conflicts (shorts). In any event, the place and route tools are far from what is really necessary to reasonably handle dynamic partial reconfiguration.

--
--Ray Andraka, P.E.
President, the Andraka Consulting Group, Inc.
401/884-7930     Fax 401/884-7950
email ray@andraka.com  
http://www.andraka.com  

 "They that give up essential liberty to obtain a little 
  temporary safety deserve neither liberty nor safety."
                                          -Benjamin Franklin, 1759

:-)

:-)

You have an excellent memory :-)

yes, several weeks if not months...

When designing these applications we apply some derating factors (derived by the customer's own -costly- qualification process), but they are surprisingly "reasonable". Power consumption is indeed a big issue with such high ambient temp. This ruled out some derived

4k families.

Our customer reports that they were surprised by the increase of quality of modern plastic packages (wrt to high temp behavior). The temperature elevation being progressive in such applications probably helps, but that's definitely not my domain of expertise.

Bert Cuzeau