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guille wrote: > > Hello there, > > Has anyone implemented a NAND interface in a PLD? I don't mean a > 'smart' NAND controller, just an interface that lets you toggle ALE, > CLE, CE externally and do read/write accesses to the NAND ports. > > Thanks, > Guillermo Rodriguez I'm not sure what you are looking for. If you control the ALE, etc, then you are talking directly to the NAND part and don't need a controller. Or are you asking how to generate ALE, CLE and the other inputs that are not typical MCU controls? The timing for these control inputs are the same as for what would be the address inputs on a NOR flash part. So I just tie them to address lines. The MCU then writes a command word by writing to an address that raises CLE and lowers ALE. It writes the address register by writing the data address to the address that lowers the CLE signal and raises the ALE signal. I don't think you need a PLD for this unless you use it to decode the address to generate the CE signal. -- 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 FAXArticle: 66027
sdatta@altera.com (Subroto Datta) writes: > Both the free Web Edition and the Quartus II Full subscription have > the same capabilities for both programming and for > generating/converting programming files. Thank you very much! Very good. (Still, I'd like to suggest that the differences between the Web edition and The Real Thing were stated very clearly on the web page.) BTW, do Altera have any plans of making Linux-compatible programmin sw? At least in our case we'd like to keep Windoze far away from the production line. - Ville -- Ville Voipio, Dr.Tech., M.Sc. (EE)Article: 66028
Peter Alfke wrote: > > Besides some meaningless semantic quibbling, Rudi's answer indicated > basic conceptual differences. > A component data sheet should have a component-centric view: The > flip-flop has a window in time during which the D-input must be stable, > to guarantee predictable operation. This window has an early edge > (commonly called set-up time, often specified as a min, but I would call > it a max), and it has a late edge (commonly called positive hold time > when it is later than the clock edge, negative hold time when it is > before the clock edge. I would like to call it the min set-up time, but > it's too late to bring sanity to this issue). > > Whether something is a min or a max depends on your perspective. > With a bridge over a highway, the "14 feet" specification is a min for > the bridge builder, but a max for the truck driver... > > Much of this is semantics, but semantics can interfere with > understanding, sometimes. > Peter Alfke I don't know if any further comment is warrented or valuable, but I am waiting for a download and thought I would post my 2 cents worth. I agree that the data sheet should be "component" centric. But this is normally done in terms of the interface. The internal sampling of the data input is what is going on, but that is not relevant given occam's razor. All the user needs to know is to maintain the data input stable during a timing window. Using one set of terms vs. the other does not make the mechanics more clear in my point of view. I agree that the basis of this timing window is not clearly understood by many engineers. The way to improve the understanding is to have the data sheets (or app notes) clearly explain the basis for the window (and how it is measured) rather than just leaving it up to the engineer to try to figure out what the data sheet writer is trying to spec. I often have trouble figuring out just what a spec is trying to say. Perhaps a JEDEC, EIA or other standards body could help by defining measurement terms, what they are measuring and how they are measured? I especially find it interesting (not in a good way) when the spec I am looking for is not in a data sheet, but instead a similar one is given in its place. For example, when I am looking for max static current draw over temperature and I am given a typical current at 25C. What is the designer trying to tell me? -- 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 FAXArticle: 66029
scale your numbers to integer, the coef width depends on the resolution(decimal points)you wish.Article: 66031
This may be an odd question but here goes... I would like to use the JTAG chain to program Xilinx's Virtex-II fpga and the Platform Flash ISP Configuration PROM. OK, that's not a problem as it's detailed in document DS123 (v2.2). However, I would like to add a second Platform Flash PROM in the same chain as the Virtex-II and it's config PROM. This second PROM would be used to hold general purpose data (ie. not FPGA config data). I would like to connect this PROM to unused I/O of the FPGA which would then reset the PROM and pull data out of it serially to be used in other parts of the product we're developing. Each "box" we're designing will have analog control bits that need to be tweaked when the unit is sealed up. The only access I have to the PROM is through the JTAG interface. I was wondering if anyone has seen any app notes detailing this sort of interface/design. PeteArticle: 66032
Peter Alfke <peter@xilinx.com> wrote in message news:<4029259F.1BC8DDF6@xilinx.com>... > This is really simple, Capitalism 101: > > Manufacturer invents and makes part. > Uses seval competing distributors to sell the part to the public. > Manufacturer optimizes his profit by charging distributor a certain > price, and also publishes a pricebook with "Manufacturer Recommended > Resale Price" MSRP. > Distributor can sell in any quantity and for any price he wants, high or > low, but he will try to optimize his profit. > Customer will buy at the lowest possible price consistent with the > desired level of service and support. > This is true for food, shirts, cars, and ICs. For Tiffany's, Nordstrom, > Safeway and CostCo. This is really simple; Oligopoly 101: Oligopolists value high order quantities highly and small order quantities as not being worth the hassle. Oligopolists watch competitors and are happy if all oligopolists in the market view small order quantities as not being worth the hassle. Certain oligopolists have a high vested interest in having smooth and monotonic price vs size curves, which can be maintained by having few distributors, and *possibly* a say on the prices they charge to buyers, and *possibly* exert pressure on distributors to toe the line. Oligopolists are happy. Those wanting to buy small order quantities are screwed. > But rest assured that we are seriously looking at ways to improve the > plight of the low-volume customer. Some of your complaints did not fall > on deaf ears. I'll quote the British phrase "the proof of the pudding is in the eating", or in other words I'll believe that when small quantity prices come down... -- SteveArticle: 66033
Ville Voipio <vvoipio@kosh.hut.fi> wrote in message news:<i3k65ednatp.fsf@kosh.hut.fi>... > armcc@lycos.com (Andre) writes: > > > Are you sure that the free version of Quartus will output .jam files > > ?? > > No, I am not sure. I did not even come to think of an alternative that > evil. By looking at the Altera site they do not mention anything about > this. This feature is not on the list of "if you pay more, you'll > get these", but that does not necessarily mean anything. > > > I thought you had to pay for the full version to anything other > > than program directly from the IDE ?? > > Possible. Let's see... Anyway, if this is the case, the CPLD on our > next design does not start with an "A". Not giving out the software > for free is one thing. Not telling the extent of the lobotomy of > the "free" version is another. > > - Ville The free Quartus II Web Edition software does output .jam files. You enable this by selecting Assignments -> Device -> Device and pin options -> programming files tab. The following page lists the general features of Quartus II Web Edition software and what additional features customers get by purchasing a software subscription: http://www.altera.com/products/software/pld/products/quartus2/sof-quarwebmain.html Rob Kruger AlteraArticle: 66034
According to the Xilinx home page two of the Spartan-3 family are in production and shipping. However, when the link is followed, one is taken to an old press release which says that four family members are shipping! Which is correct? Leon -- Leon Heller, G1HSM Email: aqzf13@dsl.pipex.com My low-cost Philips LPC210x ARM development system: http://www.geocities.com/leon_heller/lpc2104.htmlArticle: 66035
rickman wrote: > For example, when I am looking for max static current > draw over temperature and I am given a typical current at 25C. What is > the designer trying to tell me? Here is an explanation for that typical number: In the olden days, static current was extremely low, microamps or a few milliamps, and was usually swamped out by the dynamic power consumption. So the argument went this way: If the part is hot because it is working hard, running with a fast clock, nobody really cares about the leakage current. Even if it's higher than the room temp spec, it is still an insignificant part of the total current that made the chip get so hot. When the part is not working hard, it will be near room temperature, and because of the lack of dynamic power, the static current is a standby value, and may be important. And everybody knows that leakage current doubles for every 10 degree C increase in temperature. (The newly increased leakage current is actually rising less dramatically). With the recent dramatic increase in leakage current (by orders of magnitude), that old reasoning may have to be revised... Peter AlfkeArticle: 66036
The Columbia Encyclopedia describes oligopoly as: ...the control of supply by a few producers...or by agreements among members of an industry to restrain price competition... Does that describe your impression of the relationship between X and A ? Wow ! Peter Alfke =========================== Steve wrote: > This is really simple; Oligopoly 101: > > Oligopolists value high order quantities highly and small order > quantities as not being worth the hassle. > Oligopolists watch competitors and are happy if all oligopolists in > the market view small order quantities as not being worth the hassle. > Certain oligopolists have a high vested interest in having smooth and > monotonic price vs size curves, which can be maintained by having few > distributors, and *possibly* a say on the prices they charge to > buyers, and *possibly* exert pressure on distributors to toe the line. > Oligopolists are happy. > Those wanting to buy small order quantities are screwed. > > > But rest assured that we are seriously looking at ways to improve the > > plight of the low-volume customer. Some of your complaints did not fall > > on deaf ears. > > I'll quote the British phrase "the proof of the pudding is in the > eating", or in other words I'll believe that when small quantity > prices come down... > > -- > SteveArticle: 66037
Leon, Not the clearest presentation,I'll admit. Two devices, the 50J and 1000J are ES only, as they are the non-3.3V versions of the part. They are to be replaced with the non-J parts soon. There are four devices that are 3.3V compliant, and out now. Four are shipping and sampling with all features, with two of the four in production, and the remaining two in ES mode for a little longer. Sorry for the confusion. Austin Leon Heller wrote: > According to the Xilinx home page two of the Spartan-3 family are in > production and shipping. However, when the link is followed, one is > taken to an old press release which says that four family members are > shipping! Which is correct? > > LeonArticle: 66038
When was the last time you asked for technical support on a resistor? Part of the pricing
pays for the tech support, which is more or less a per customer charge rather than a per piece
charge. Naturally, if you are buying a large quantity, the tech support per peice is going to
be considerably less. Tech support is one of the distributor's largest costs.
Jim Granville wrote:
> William Wallace wrote:
> > rickman <spamgoeshere4@yahoo.com> wrote in message news:<40286B1C.8BD933C4@yahoo.com>...
> <snip>
> >>
> >>And you will pay some 3 or 4 times what you would pay if you were buying
> >>1000's. I know, I have looked.
> >>
> >
> >
> > How is this any different than any other product? Resistors, for
> > example. Go to digikey and try to buy 3 0805 100 Ohm resistors. Your
> > price per resistor will be much higher than if you bought several
> > dozen reels from a distributor.
>
> I don't think anyone expects a flat price curve ( except in the
> promotion special case I mentioned earlier ).
>
> What is at issue, is the lazy application of the jelly-bean-resistor
> type price curves to much more expensive parts.
>
> Each sales transacton has a cost, and each customer call has a cost,
> but those costs do not scale with the device price.
>
> eg
> A price structure that has a 1 off price of $15, and volume price of $4
> is probably OK to most users.
> What's harder to justify, is a 1 off price of $150, and volume price of
> $40.
> In one case you are saying "it costs $11 more to handle small volumes"
> - fine, but how can that possibly justify $110 extra on the larger
> device - ?
>
> -jg
--
--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
Article: 66039Austin Lesea <austin@xilinx.com> wrote: : Leon, : Not the clearest presentation,I'll admit. : Two devices, the 50J and 1000J are ES only, as they are the non-3.3V : versions of the part. They are to be replaced with the non-J parts soon. : There are four devices that are 3.3V compliant, and out now. : Four are shipping and sampling with all features, with two of the four : in production, and the remaining two in ES mode for a little longer. : Sorry for the confusion. When can we expect these parts to be available at distributors? E.g. nuhorizons list no XC3S available at the moment. Bye -- Uwe Bonnes bon@elektron.ikp.physik.tu-darmstadt.de Institut fuer Kernphysik Schlossgartenstrasse 9 64289 Darmstadt --------- Tel. 06151 162516 -------- Fax. 06151 164321 ----------Article: 66040
the naming of elements built by a generate statement is not
specified by the LRM, and is not consistent from tool to
tool. To make it portable, as well as easier on yourself,
put the attribute in the generate statement declaration
rather than outside. Also, you'll need to specify the value
for the generic with a generic map so that simulation
matches the hardware:
----------------------------
> architecture ...
>
> component ROM128X1
> -- synthesis translate_off
> generic (INIT : bit_vector := X"128");
> -- synthesis translate_on
> port (
> O : out std_ulogic;
> A0 : in std_ulogic;
> A1 : in std_ulogic;
> A2 : in std_ulogic;
> A3 : in std_ulogic;
> A4 : in std_ulogic;
> A5 : in std_ulogic;
> A6 : in std_ulogic
> );
> end component;
>
> attribute INIT : string;
>
> begin
> t : for i in 0 to 1 generate
attribute INIT of U:label is "..";
>
> U : ROM128X1
generic map(
INIT => "...")
>
> port map(
> O => data_out(i),
> A0 => addr_in(0),
> A1 => addr_in(1),
> A2 => addr_in(2),
> A3 => addr_in(3),
> A4 => addr_in(4),
> A5 => addr_in(5),
> A6 => addr_in(6)
> );
> end generate;
> end;
--
--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
Article: 66041> Four are shipping and sampling with all features, with two of the four > in production, and the remaining two in ES mode for a little longer. Austin, Is that four parts in all footprints or four part/ footprint combinations? Any more details on which four? A client on mine has just spent a desperate couple of days trying to source a Spartan3 device they've designed in to their next generation product, they only need a few (<10) for prototyping. Any of the footprint compatible parts would probably do, but it's hard finding out what's available. Nial ------------------------------------------------ Nial Stewart Developments Ltd FPGA and High Speed Digital Design www.nialstewartdevelopments.co.ukArticle: 66042
Uwe, The upturn in the electronics industry caught everyone off-guard. As was disclosed in our last fiscal report, the Q to Q numbers were up 16%, which is a lot like saying "wow!" or maybe "ouch!" -- depends on your point of view. Unfortunately, we have to build our chips in advance of their need, and the fab cycle is not getting any shorter as the technology gets smaller. No one was willing to make any committments in November. Now everyone wants parts, and lots of them. It is not only S3, but even some of the older parts as well. Thus, the chips we find today to ship started their life sometime in the summer and early fall based on the projections and orders that we had, and anticipated. We are doing our best to meet all requests. Austin Uwe Bonnes wrote: > Austin Lesea <austin@xilinx.com> wrote: > : Leon, > > : Not the clearest presentation,I'll admit. > > : Two devices, the 50J and 1000J are ES only, as they are the non-3.3V > : versions of the part. They are to be replaced with the non-J parts soon. > > : There are four devices that are 3.3V compliant, and out now. > > : Four are shipping and sampling with all features, with two of the four > : in production, and the remaining two in ES mode for a little longer. > > : Sorry for the confusion. > > When can we expect these parts to be available at distributors? > E.g. nuhorizons list no XC3S available at the moment. > > ByeArticle: 66043
Nial, FAEs have the documents, so I would suggest they put in the request to find out from them. Austin Nial Stewart wrote: >>Four are shipping and sampling with all features, with two of the four >>in production, and the remaining two in ES mode for a little longer. > > > Austin, > > Is that four parts in all footprints or four part/ > footprint combinations? > > Any more details on which four? > > A client on mine has just spent a desperate couple of > days trying to source a Spartan3 device they've designed > in to their next generation product, they only need > a few (<10) for prototyping. > > Any of the footprint compatible parts would probably > do, but it's hard finding out what's available. > > > Nial > > > ------------------------------------------------ > Nial Stewart Developments Ltd > FPGA and High Speed Digital Design > www.nialstewartdevelopments.co.uk > > >Article: 66044
Peter Alfke wrote: > rickman wrote: > >> For example, when I am looking for max static current >>draw over temperature and I am given a typical current at 25C. What is >>the designer trying to tell me? > > > Here is an explanation for that typical number: > In the olden days, static current was extremely low, microamps or a few > milliamps, and was usually swamped out by the dynamic power consumption. > > So the argument went this way: > If the part is hot because it is working hard, running with a fast > clock, nobody really cares about the leakage current. Even if it's > higher than the room temp spec, it is still an insignificant part of the > total current that made the chip get so hot. > > When the part is not working hard, it will be near room temperature, and > because of the lack of dynamic power, the static current is a standby > value, and may be important. And everybody knows that leakage current > doubles for every 10 degree C increase in temperature. (The newly > increased leakage current is actually rising less dramatically). > > With the recent dramatic increase in leakage current (by orders of > magnitude), that old reasoning may have to be revised... ... and designs need to consider complete power removal of those hungry devices during sleep times, which moves away from a single chip solution.. > > Peter Alfke I think rickman was asking about TYP vs MAX ? Typical appears on a data sheet for many reasons : - It's a better sounding number (don't laugh..) - It's easier/quicker to derive than a MAX corner value. - It's also usefull for average battery life calculations. but sometimes, customers want to know worst case battery life, and they may even be using batteries good enough to spec that over temperature. So they need a corresponding chip value. If the spec omits MAX, the designer could be trying to say any or all of : - The silicon is so new, we don't know this number yet - Our test coverage could not guarantee this on all devices - We do not bother to test it - A few devices have this very high, and we are unsure why - Why does that number matter again ? The new Lattice 4000 family, and Xilinx Coolrunner II do seem to have good Typ, and Max static Icc specs, so perhaps those customers are more demanding ? Personally, I prefer to see Icc vs Temp plots, and in the old days of data sheets, they would plot Typ and Max on the same graph! -jgArticle: 66045
Ray Andraka wrote: > When was the last time you asked for technical support on a resistor? Actually, more recently than I asked for support on a CPLD ;) but I do get your point... > Part of the pricing > pays for the tech support, which is more or less a per customer charge rather than a per piece > charge. Naturally, if you are buying a large quantity, the tech support per peice is going to > be considerably less. Tech support is one of the distributor's largest costs. I believe I said that. The question is how to justify the $40 -> $150, alongside the $4 -> $15 device price/volume curve. FPGAs are a great example of where bigger devices just give you more of everything - the software tools are identical, and in most cases so are the building blocks, and even large chunks of data. So the tech support cost of the large/small fpgas are largely similar. The real reasons for such lazy pricing have more to do with the bean-counters, and wanting to have a certain % margin on stock. Which is OK if the disti's actually HAVE stock... Solution would be to have a WEB page sales system, that has a relatively high ($20-$30-?) line item processing charge, and a more sensible true device cost on the silicon itself. Still makes a nominal profit, but accelerates the design-wins, and ramp-ups of the devices... -jgArticle: 66046
Steve wrote: > > Peter Alfke <peter@xilinx.com> wrote in message news:<4029259F.1BC8DDF6@xilinx.com>... > > This is really simple, Capitalism 101: > > > > Manufacturer invents and makes part. > > Uses seval competing distributors to sell the part to the public. > > Manufacturer optimizes his profit by charging distributor a certain > > price, and also publishes a pricebook with "Manufacturer Recommended > > Resale Price" MSRP. > > Distributor can sell in any quantity and for any price he wants, high or > > low, but he will try to optimize his profit. > > Customer will buy at the lowest possible price consistent with the > > desired level of service and support. > > This is true for food, shirts, cars, and ICs. For Tiffany's, Nordstrom, > > Safeway and CostCo. > > This is really simple; Oligopoly 101: > > Oligopolists value high order quantities highly and small order > quantities as not being worth the hassle. > Oligopolists watch competitors and are happy if all oligopolists in > the market view small order quantities as not being worth the hassle. > Certain oligopolists have a high vested interest in having smooth and > monotonic price vs size curves, which can be maintained by having few > distributors, and *possibly* a say on the prices they charge to > buyers, and *possibly* exert pressure on distributors to toe the line. > Oligopolists are happy. > Those wanting to buy small order quantities are screwed. > > > But rest assured that we are seriously looking at ways to improve the > > plight of the low-volume customer. Some of your complaints did not fall > > on deaf ears. > > I'll quote the British phrase "the proof of the pudding is in the > eating", or in other words I'll believe that when small quantity > prices come down... > > -- > Steve Hey Steve, why don't you get off the soapbox. What you are doing is not getting you anywhere and is starting to tick me off. Until you give a call to your distributor and *ask* what price you can get, I don't want to listen to your rants. Don't make me come over there... ;) -- 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 FAXArticle: 66047
Peter Alfke wrote: > > rickman wrote: > > For example, when I am looking for max static current > > draw over temperature and I am given a typical current at 25C. What is > > the designer trying to tell me? > > Here is an explanation for that typical number: > In the olden days, static current was extremely low, microamps or a few > milliamps, and was usually swamped out by the dynamic power consumption. > > So the argument went this way: > If the part is hot because it is working hard, running with a fast > clock, nobody really cares about the leakage current. Even if it's > higher than the room temp spec, it is still an insignificant part of the > total current that made the chip get so hot. > > When the part is not working hard, it will be near room temperature, and > because of the lack of dynamic power, the static current is a standby > value, and may be important. And everybody knows that leakage current > doubles for every 10 degree C increase in temperature. (The newly > increased leakage current is actually rising less dramatically). > > With the recent dramatic increase in leakage current (by orders of > magnitude), that old reasoning may have to be revised... > > Peter Alfke Uh, what if "room temp" is 85C? That is a valid operating spec for many chips, right? That was just one example I could think of off the top of my head. There are lots of timing related specs or even functional specs that are just not clear in many data sheets. I think that often these specs reflect how the parts are tested, without thorough consideration of how they are used. -- 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 FAXArticle: 66049
Hi all I need some help with regards to generating a sine wave. I thought abt this problem and some thoughts that came to mind are as follows: 1. Generate sine values using spreadsheet 2. Store these values either in ROM or make a table withing VHDL 3. Write VHDL code and output these values. My question is: Is it better to store these values in ROM (eg. LUT) or directly hardcode the values. Is there a website that will explain or give more explanation in this area. Cheers
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