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On Feb 25, 11:34=A0am, Andy <jonesa...@comcast.net> wrote:
> On Feb 25, 5:49=A0am, rickman <gnu...@gmail.com> wrote:
>
> > If the combinatorial logic had been described in the sequential
> > process, there would have been no possibility of generating a latch.
>
> Amen!
>
> Andy
Rick,
Try this one and there is no lock problem any more in VHDL. See what
happens.
CombProc : process(CombReg, C01, C02)
begin
case CombReg is
when '1' =3D> <-- only change, and not locked again
if (C01 =3D '1') then
Comb <=3D '0';
elsif (C02 =3D '1') then
Comb <=3D '1';
else
null;
end if;
when others =3D>
Comb <=3D '1';
end case;
end process;
Thank you.
Weng
Article: 145851"(see below)" <yaldnif.w@blueyonder.co.uk> writes: >On 25/02/2010 23:26, in article SGDhn.70229$Hk6.39325@news.usenetserver.com, >"Scott Lurndal" <scott@slp53.sl.home> wrote: > >> "(see below)" <yaldnif.w@blueyonder.co.uk> writes: >>> On 24/02/2010 20:37, in article hm6fbd68gp@news6.newsguy.com, "Michael >>> Wojcik" <mwojcik@newsguy.com> wrote: >>> >>>> (see below) wrote: >>>>> >>>>> Just the usual red tape: return address, frame pointer of caller; and >>>>> either >>>>> a static pointer or some housekeeping for 'display' registers (if used) to >>>>> access non-locals. But bear in mind that in decent languages arrays are >>>>> storable values, so a value array parameter gets copied in toto, unlike C. >>>> >>>> It will be in C if the array is wrapped in a struct. Letting array >>> >>> That is passing a struct, not an array. >>> >>>> parameters decay to pointers was a feature of early C that couldn't be >>>> changed for historical reasons, but when the standardization committee >>>> added support for struct parameters, they made them first-class. >>> >>>> struct (and not the misnamed "typedef") is C's mechanism for creating >>>> new types and ADTs, so if you want a pass-by-value array in C, the >>>> correct thing to do is to put it in a struct. >>> >>> Yes. Preposterous, isn't it? >> >> Q? Why would anyone want to pass an array by value? > >Why would anyone want to wrap an array in a struct and pass that by value? Why answer a question with another question? I've never promoted or suggested that one put an array in a struct and pass it by value, I frankly think it would be a stupid thing to do in a C program. I was curious if anyone thought passing an array by value was a _good_ idea. scottArticle: 145852
In comp.arch.fpga Scott Lurndal <scott@slp53.sl.home> wrote: (snip, someone wrote) >>> Q? Why would anyone want to pass an array by value? >>Why would anyone want to wrap an array in a struct and pass that by value? > Why answer a question with another question? > I've never promoted or suggested that one put an array in a struct > and pass it by value, I frankly think it would be a stupid thing to > do in a C program. It might make sense for a small array. You might have an rgb array dimensioned [3] instead of three separae variables. The dimension, I believe, has to be a compile time constant. -- glenArticle: 145853
On Feb 25, 2:04=A0pm, austin <aus...@xilinx.com> wrote: > John, > > I just love the Dilbert cartoon where they try to out-do each other > about the 'old days:' > > "I used to program in 1's and 0's!" > > "That's nothing, all we had were l's and O's ( small letter L and > capital letter O)" > > "Heck, all I had were 0's...." > > Yes, I have some 1702's, along with the 4004 4 bit CPU, and some 2102 > SRAM devices Intel handed out to customers to "introduce" them to the > microcomputer. > > I just remember that if you put the 1702 in the socket rotated 180 > degrees, it blew out all the bond wires. =A0Someone came to the lab one > day saying "did you know that the EPROM lights up when you program > it?" > > Austin Austin - I was at a company that create a dual 4004 syetem for reading digital holograms. It was quite an eye opener for me - senior in high school working at a company with a ton of leading edge technology. I still have my 4004 programming cheat-sheet. JohnArticle: 145854
glen herrmannsfeldt <gah@ugcs.caltech.edu> writes:
> In comp.arch.fpga Scott Lurndal <scott@slp53.sl.home> wrote:
> (snip, someone wrote)
>>>> Q? Why would anyone want to pass an array by value?
>
>>>Why would anyone want to wrap an array in a struct and pass that by value?
>
>> Why answer a question with another question?
>
>> I've never promoted or suggested that one put an array in a struct
>> and pass it by value, I frankly think it would be a stupid thing to
>> do in a C program.
>
> It might make sense for a small array. You might have an rgb
> array dimensioned [3] instead of three separae variables.
> The dimension, I believe, has to be a compile time constant.
It doesn't. You can use malloc() to allocate an arbitrary-sized buffer,
and then use array syntax to access elements of the buffer. You can
also pass the address of the buffer, and use it like an array in the
called procedure.
Since C99, you can allocate an array with a variable number of elements
like this:
printf(" array size >> ");
scanf("%d", &size);
int awry[size];
--
As we enjoy great advantages from the inventions of others, we should
be glad of an opportunity to serve others by any invention of ours;
and this we should do freely and generously. (Benjamin Franklin)
Article: 145855On Feb 26, 12:02=A0am, -jg <jim.granvi...@gmail.com> wrote: > On Feb 25, 11:18=A0pm, Antti <antti.luk...@googlemail.com> wrote: > > > but the time til embedded is just crazy all things happening at worst t= ime.. as usual :) > > So what's going to be new @ embedded ? ;) > > -jg i will know next week :) hm ah, from me? not so much actually most projects still in late development stage :( anttiArticle: 145856
Sometimes vendors act like they don't want you to use their parts. I am looking for rise/fall time information on an FPGA output in one voltage mode LVCMOS33 and the various drive and slew rate options. This doesn't sound like a difficult thing to ask for, but it seems to be a very difficult thing to get. I recall the rise/fall times to be something that is very common in data sheets. They just pick a set of conditions and give the data. Even if that does not match your circuit design perfectly, it is a data point to start with. In my case, I am seeing a ridiculously slow rise time with the current setting which happens to be the lowest current and slowest slew rate. I guess that is not unexpected. In fact, I'm a bit surprised we didn't see a problem with it before now. If I go with the highest drive and fast slew rate, I get very significant overshoot which is also not surprising. So obviously I need to find a happy medium. I could make up some boards with different drive settings and see how they work, but there are 10 combinations total and this is a bit of a PITA and has to involve my customer to make the measurements. Since they don't include rise time info in the data sheet, I thought, maybe I'll contact support and get the info. That was last Friday when I called thinking this was such a simple request that maybe they could answer the question on the phone... silly me. I have not received a reply from that contact yet! Yesterday I got tired of waiting and in addition to pinging support by email, I made a post in their forum. That seems to have gotten a response but not an answer. I am repeatedly told that the info would do me no good since it would not match my circuit; I can get this info from an IBIS simulation and several other ideas of how to get the info... meanwhile I'm not actually getting the info from support. I don't have a way to simulate IBIS models. I tried to convert the IBIS file to a spice model, but the resulting file was not compatible with the spice I use. I was told to manually read the IBIS model, but it is a huge thing that includes all of the IO modes with such cryptic names that I have no way of knowing which section is for which IO setting. They even have been giving me advice on how to properly design a transmission line! The guy has all but written a book of advice for me on all this, but none of the solutions work for me. It just seems absurd that support is going to so much trouble to give me advice I don't want in lieu of some very simple data I do want. So I am going to have to build a bit file with each of the various setting combinations and spend the afternoon measuring each one. It just seems like such a waste of time, but it will be easier than trying to pass the camel of support through the eye of the needle of my question. RickArticle: 145857
glen herrmannsfeldt wrote:
>
> [snip...] [snip...] [snip...]
>
>> As Al Stewart once sang, "I was jumping to conclusions, and one of them
>> jumped back."
>
"If you stare into the Abyss long enough,
the Abyss stares back at you."
-- Friedrich Nietzsche
--
+----------------------------------------+
| Charles and Francis Richmond |
| |
| plano dot net at aquaporin4 dot com |
+----------------------------------------+
Article: 145858glen herrmannsfeldt wrote: > In comp.arch.fpga Scott Lurndal <scott@slp53.sl.home> wrote: > (snip, someone wrote) >>>> Q? Why would anyone want to pass an array by value? > >>> Why would anyone want to wrap an array in a struct and pass that by value? > >> Why answer a question with another question? > >> I've never promoted or suggested that one put an array in a struct >> and pass it by value, I frankly think it would be a stupid thing to >> do in a C program. > > It might make sense for a small array. You might have an rgb > array dimensioned [3] instead of three separae variables. > The dimension, I believe, has to be a compile time constant. > > -- glen Heck, for RGB, just use a struct with three variables in it. The dimensions of arrays *used* to have to be compile time constants. Now they have a type of array declared in a function that can have its size depend on an integer passed into the function. (I forget what they call it... maybe a "dynamic array" or something.) -- +----------------------------------------+ | Charles and Francis Richmond | | | | plano dot net at aquaporin4 dot com | +----------------------------------------+Article: 145859
Joe Pfeiffer wrote:
> glen herrmannsfeldt <gah@ugcs.caltech.edu> writes:
>
>> In comp.arch.fpga Scott Lurndal <scott@slp53.sl.home> wrote:
>> (snip, someone wrote)
>>>>> Q? Why would anyone want to pass an array by value?
>>>> Why would anyone want to wrap an array in a struct and pass that by value?
>>
>>> Why answer a question with another question?
>>
>>> I've never promoted or suggested that one put an array in a struct
>>> and pass it by value, I frankly think it would be a stupid thing to
>>> do in a C program.
>> It might make sense for a small array. You might have an rgb
>> array dimensioned [3] instead of three separae variables.
>> The dimension, I believe, has to be a compile time constant.
>
> It doesn't. You can use malloc() to allocate an arbitrary-sized buffer,
> and then use array syntax to access elements of the buffer. You can
> also pass the address of the buffer, and use it like an array in the
> called procedure.
>
> Since C99, you can allocate an array with a variable number of elements
> like this:
>
> printf(" array size >> ");
> scanf("%d", &size);
>
> int awry[size];
But how about the second dimension, Joe??? Can you allocate:
int awry2[size][size];
--
+----------------------------------------+
| Charles and Francis Richmond |
| |
| plano dot net at aquaporin4 dot com |
+----------------------------------------+
Article: 145860On 25 Feb., 11:21, Petter Gustad <newsmailco...@gustad.com> wrote: > On the other hand the Synopsys VCS simulator is not available for > Windows. Last time I used Synopsys Simulator is 10 years ago, but I don't missed it since then :). > > Several parts of the design suites ISPLever are Windows only, > > Programming Actel FPGAs is only possible using Windows... > > Does that mean you can't generate a SVF file either? You can generate a programming file under linux. But you can't use the programmer (and programmer SW) neither for Antifuse nor for Flash- based. The core generator for more complex cores(PCI and so on) also requires Windows. And as already stated, the actual version of designer under Linux is to slow to do reasonable layout/floorplan of complex designs. bye ThomasArticle: 145861
In comp.arch.fpga Charles Richmond <frizzle@tx.rr.com> wrote: (snip) > Heck, for RGB, just use a struct with three variables in it. Well, the suggestion was an array in a struct. With an array you can loop over it. > The dimensions of arrays *used* to have to be compile time > constants. Now they have a type of array declared in a function > that can have its size depend on an integer passed into the > function. (I forget what they call it... maybe a "dynamic array" > or something.) Yes, but can you do that for an array in a struct. If you pass it in a function call, and it isn't the last argument, how will the called routine know where the other arguments are? I haven't done much with C99 yet. -- glenArticle: 145862
Thomas Stanka <usenet_nospam_valid@stanka-web.de> writes: > Last time I used Synopsys Simulator is 10 years ago, but I don't > missed it since then :). I've used VCS since it was first released by Chronologic until two years ago, since then I've used ModelSim and I really miss VCS... >> > Several parts of the design suites ISPLever are Windows only, >> > Programming Actel FPGAs is only possible using Windows... >> >> Does that mean you can't generate a SVF file either? > > You can generate a programming file under linux. But you can't use the > programmer (and programmer SW) neither for Antifuse nor for Flash- > based. > The core generator for more complex cores(PCI and so on) also requires > Windows. > And as already stated, the actual version of designer under Linux is > to slow to do reasonable layout/floorplan of complex designs. It's probably a tough job for the smaller companies to develop multi-platform software since they don't have the resources that Xilinx and Altera has. However, it could have been interesting if some of the smaller vendors would open source their software to get some community help. But some of their software might be based upon some commercial packages outside their control, which makes it impossible unless it's re-written. Petter -- A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing on usenet and in e-mail?Article: 145863
On 25/02/2010 13:56, rickman wrote: > On Feb 25, 6:04 am, Symon<symon_bre...@hotmail.com> wrote: >> If anyone from Altera reads this forum, can they please email/call their >> manual writing& publishing department and complain from me that their >> stupid PDF manuals have occasional pages turned at 90 degrees, e.g. the >> Stratix4 Handbook, page 1-11. This is very annoying, as it means my >> reader displays all the other pages narrower than they would be. I'm >> getting on a bit now, my eyesight isn't what it was, and I'm too >> cantankerous to piss about with the magnifying glass tool. I'm perfectly >> capable of using the special rotate button that the reader provides for >> the odd occasion when the page needs to be turned, in the same way I >> used to be able to turn a book in the good old days. Those dumbasses >> (probably) wouldn't print a book with occasional pages sticking out, why >> do they feel the need to do it with their PDF manuals. >> >> The stupid thing is, doing what they have done, doesn't make the table >> any easier to read on a computer screen than if they'd made the table >> smaller and printed it across the page. It just makes all the other >> pages harder to read. The only time it helps is if some bozo decides >> he's gonna print out 27MB of file, in which case they're probably a >> student and have good eyesight anyway. >> >> This is the only reason stopping me from designing in Altera parts. >> Xilinx have nice PDF files. >> >> Love, Syms. >> >> p.s. There's no charge for this free advice. > > Maybe you should instead complain to Adobe about their *stupid* PDF > reading software. The only reason that the rotated pages are making > the others hard to view is because you are using "fit to page width" > for a magnification. In lieu of getting either of these multi- I can't see this effect with any pdf reader I've tried - Foxit which I normally use on Windows, evince on Ubuntu, or Acrobat Reader 8 on Windows. Maybe you are using an old version of Acrobat Reader? It makes sense to complain to Adobe about how they have managed to make such an insecure file reader, or to ask why they have allowed executable javascript and plugins by default, or why their software is orders of magnitude bigger, slower, and more ram-hungry than alternatives such as Foxit. But I am totally failing to replicate these viewing problems. > national corporations to change the way they do business, perhaps you > could do a very little leg work yourself. One is to just view them > with a set magnification which will show all pages at the same zoom > level. It's not really so hard to do. You just type in a zoom level > that lets you view the first page to fit the width of the window. > > The other method can only be done if Altera has not write or read > protected their data sheets. You can use a PDF editing tool to > actually rotate the page in the document and then save it so it will > be forever fixed. If you find that Altera's data sheets are write > protected, then you are screwed. I have seen some data sheets that > are *read* protected, or more accurately, copy protected. Yes, they > prevent you from using select, copy and paste to pull any information > out of the document. I find that insane and it drives me pretty much > up a wall. If I want to quote something from a data sheet, such as a > part number for ordering, I want to *COPY* it so as to eliminate the > possibility of a transcription error. With part number containing > some 12 or more digits and letters, it is oh so easy to mess it up. > Even more interesting is when I find a document that is protected in > some way, but they forgot to password protect it, so I can turn off > the protection... But I think you can use some third party tools to > get around the password protection. After all, if you can read the > document so that it can be viewed, you can always copy and/or edit > it. The "protection" is just a switch in the program you are reading > it with. > Rather than going through all this effort, install a decent (free and open-source) pdf printer such as PDFCreator. Then you can "print" your document to a new pdf file that has all the pages at the same orientation, and is certainly editable if you want. > BTW, you can blame all of this on the community standardizing on a > proprietary document format instead of open source. There seem to be > open source tools for PDF files now, but it has taken a long time and > most people don't know about them. > PDF came from a proprietary source, but it is an ISO standard (at least, for some version of pdf format) now. The format has been well known since it became popular, and there have been open source tools for PDF reading, generation, and editing for years - the xpdf viewer is at least 14 years old, and pdfLatex for generating pdf files is at least 12 years old. While the pdf standard could be more "open", it is pretty good as standards go.Article: 145864
rickman <gnuarm@gmail.com> wrote: > Sometimes vendors act like they don't want you to use their parts. I > am looking for rise/fall time information on an FPGA output in one > voltage mode LVCMOS33 and the various drive and slew rate options. > This doesn't sound like a difficult thing to ask for, but it seems to > be a very difficult thing to get. I recall the rise/fall times to be > something that is very common in data sheets. They just pick a set of > conditions and give the data. Even if that does not match your > circuit design perfectly, it is a data point to start with. > In my case, I am seeing a ridiculously slow rise time with the current > setting which happens to be the lowest current and slowest slew rate. > I guess that is not unexpected. In fact, I'm a bit surprised we > didn't see a problem with it before now. If I go with the highest > drive and fast slew rate, I get very significant overshoot which is > also not surprising. Go back to the basic, starting without transmission line effects. With 10 mA source current and 10 pf load, dU/dt = 10 mA/10pF = 1V/nS 10 pF is probably no bad guestimate for one output with one pin load and some trace... So probably series termination is another approach you should consider. Bye -- Uwe Bonnes bon@elektron.ikp.physik.tu-darmstadt.de Institut fuer Kernphysik Schlossgartenstrasse 9 64289 Darmstadt --------- Tel. 06151 162516 -------- Fax. 06151 164321 ----------Article: 145865
On 25/02/2010 15:43, Symon wrote: > On 2/25/2010 12:56 PM, rickman wrote: >> >> The other method can only be done if Altera has not write or read >> protected their data sheets. You can use a PDF editing tool to >> actually rotate the page in the document and then save it so it will >> be forever fixed. > > Actually, that provoked me. You need Acrobat professional. Which isn't > free. > Since you already use Foxit for reading, you should probably look at Foxit Editor rather than Acrobat Writer. I've not used it myself, but considering how much better Foxit reader is than Acrobat reader, I'd look there first. pdfedit is an alternative for Linux, but it's a bit slow, and it Foxit has trouble reading the files it produces (apparently it's a bug in Foxit, not pdfedit). > > File-> Create PDF -> from file > > Document -> Rotate Pages -> > Counterclockwise 90 degrees > Landscape pages > > Lovely. Maybe I will use their parts after all. It's still dumb the way > they publish the PDFs. > > Syms.Article: 145866
On 2/26/2010 9:43 AM, David Brown wrote: > Foxit. But I am totally failing to replicate these viewing problems. > Hi David, I don't like to see failure. I have Foxit 3.1.4.1125, which seems quite up-to-date. I have set the default to show the pages at their biggest, i.e. 'fit width', because I am getting old and my eyes aren't like they used to be. When I load :- http://www.altera.com/literature/hb/stratix-iv/stx4_siv51001.pdf The portrait pages in it, e.g. pg 1-1, no longer 'fit width', because there are pages like 1-11 that, and this is my complaint, are included in landscape mode. The reader's rotate button doesn't help, 'cos it rotates every page. The solution is to publish documents with all pages portrait and draw the tables across the page. This is 'totally' driving me bonkers, and is why I keep clogging up the useful discourse on CAF with these ridiculous posts. If you don't see this effect, please, for God's sake, put me out of my misery, and let me know what you did. Thanks, Syms. p.s. A similar thing happens in my old version 7 Adobe viewer, but only after the viewer has 'seen' a landscape page.Article: 145867
On Feb 26, 4:52=A0am, Uwe Bonnes <b...@elektron.ikp.physik.tu- darmstadt.de> wrote: > rickman <gnu...@gmail.com> wrote: > > Sometimes vendors act like they don't want you to use their parts. =A0I > > am looking for rise/fall time information on an FPGA output in one > > voltage mode LVCMOS33 and the various drive and slew rate options. > > This doesn't sound like a difficult thing to ask for, but it seems to > > be a very difficult thing to get. =A0I recall the rise/fall times to be > > something that is very common in data sheets. =A0They just pick a set o= f > > conditions and give the data. =A0Even if that does not match your > > circuit design perfectly, it is a data point to start with. > > In my case, I am seeing a ridiculously slow rise time with the current > > setting which happens to be the lowest current and slowest slew rate. > > I guess that is not unexpected. =A0In fact, I'm a bit surprised we > > didn't see a problem with it before now. If I go with the highest > > drive and fast slew rate, I get very significant overshoot which is > > also not surprising. > > Go back to the basic, starting without transmission line effects. > With 10 mA source current and 10 pf load, dU/dt =3D 10 mA/10pF =3D 1V/nS > > 10 pF is probably no bad guestimate for one output with one pin load and > some trace... > > So probably series termination is another approach you should consider. Where did you get any of the data you are talking about? How did you come up with 10 mA? I could have done all sorts of things if I want to make assumptions, but they would be just that, assumptions and not information. The settings include current drive of 4, 8, 12, 16 and 20 mA along with speed settings of FAST and SLOW. Clearly you can't just do a calculation based on the rated current since that would leave no room for the FAST/SLOW setting. I believe I was told by one of the FPGA vendors that their parts had current controlled internal nodes which could set the slew rate. So it may be that the speed setting alone controls the slew rate of a bare pin. Like I said, that would be a good start, but until I can get an informative reply I am left only with building 10 different bit files, loading up 10 different boards and taking 10 measurements. Not my idea of a fun afternoon. RickArticle: 145868
On Feb 26, 5:38=A0am, Symon <symon_bre...@hotmail.com> wrote: > On 2/26/2010 9:43 AM, David Brown wrote: > > > Foxit. But I am totally failing to replicate these viewing problems. > > Hi David, > > I don't like to see failure. > > I have Foxit 3.1.4.1125, which seems quite up-to-date. > > I have set the default to show the pages at their biggest, i.e. 'fit > width', because I am getting old and my eyes aren't like they used to > be. When I load :- > > http://www.altera.com/literature/hb/stratix-iv/stx4_siv51001.pdf > > The portrait pages in it, e.g. pg 1-1, no longer 'fit width', because > there are pages like 1-11 that, and this is my complaint, are included > in landscape mode. The reader's rotate button doesn't help, 'cos it > rotates every page. The solution is to publish documents with all pages > portrait and draw the tables across the page. > > This is 'totally' driving me bonkers, and is why I keep clogging up the > useful discourse on CAF with these ridiculous posts. > > If you don't see this effect, please, for God's sake, put me out of my > misery, and let me know what you did. > > Thanks, Syms. > > p.s. A similar thing happens in my old version 7 Adobe viewer, but only > after the viewer has 'seen' a landscape page. I've seen this before in Acrobat and it shows up when the document is opened. There are settings that control the initial view and I didn't explore how they were set, but it was due to a page being landscape controlling the default magnification of the entire document. Like I said before, I have my own nits to pick with data sheets and it really does make a difference about what parts I consider. Heck, there is an inductor company that puts everything on web pages and not even all on one page! You have to visit multiple pages to get all the data on their parts. Maybe they have updated by now, but have I never used any of their parts because it was such a PITA to store the data sheet. RickArticle: 145869
> The > settings include current drive of 4, 8, 12, 16 and 20 mA along with > speed settings of FAST and SLOW. Clearly you can't just do a > calculation based on the rated current since that would leave no room > for the FAST/SLOW setting. I might be wrong, but I _think_ that in Quartus a FAST or SLOW assignment overrides the current setting, so that's fewer variations to worry about. > I am left only > with building 10 different bit files, loading up 10 different boards > and taking 10 measurements. Not my idea of a fun afternoon. Sure it wouldn't take too long to knock up a mickey mouse design that just toggles a single pin then vary the assignments. You could have a new test re-built and programmed in a minute or two. Or are there other constraints? Nial.Article: 145870
On Wed, 24 Feb 2010 11:31:45 -0800 (PST) Eric Chomko <pne.chomko@comcast.net> wrote: > On Feb 23, 2:07 pm, "(see below)" <yaldni...@blueyonder.co.uk> wrote: > > On 23/02/2010 17:52, in article > > 3ec03225-3a0f-4bcd-9db1-51201d1b3...@w12g2000vbj.googlegroups.com, "Eric > > > > Chomko" <pne.cho...@comcast.net> wrote: > > > But an ALGOL "activation record" (stack frame) had a lot more than > > > that. As I recall, they copied a lot more just pointers and parameter > > > values. > > > > Just the usual red tape: return address, frame pointer of caller; and > > either a static pointer or some housekeeping for 'display' registers > > (if used) to access non-locals. But bear in mind that in decent > > languages arrays are storable values, so a value array parameter gets > > copied in toto, unlike C. > > > > Are you saying that C doesn't implement true recursion? I have only No, he's saying that C doesn't really implement an array type, the var[offset] syntax is just syntactic sugar for *(var + offset) which is why things like 3[x] work the same as x[3] in C. -- Steve O'Hara-Smith | Directable Mirror Arrays C:>WIN | A better way to focus the sun The computer obeys and wins. | licences available see You lose and Bill collects. | http://www.sohara.org/Article: 145871
If I was gonna guess how FPGA's outputs with programmable drive and slew work, I'd say there are a bunch of FETs in parallel, turning on more of them for more drive. So, for 2mA, just one FET gets turned on, for 24mA, all of them do. The gate current to these FETs can be limited, which gives slower skew, or not limited which means they go as fast as possible. It would be impossible for a vendor to publish a 'rise time' for these devices, because of the many different settings, which is why the IBIS files are great. Cheers, Syms.Article: 145872
On 26/02/2010 11:38, Symon wrote: > On 2/26/2010 9:43 AM, David Brown wrote: > >> Foxit. But I am totally failing to replicate these viewing problems. >> > > Hi David, > > I don't like to see failure. > > I have Foxit 3.1.4.1125, which seems quite up-to-date. > That's what I am using too. > I have set the default to show the pages at their biggest, i.e. 'fit > width', because I am getting old and my eyes aren't like they used to > be. When I load :- > > http://www.altera.com/literature/hb/stratix-iv/stx4_siv51001.pdf > > The portrait pages in it, e.g. pg 1-1, no longer 'fit width', because > there are pages like 1-11 that, and this is my complaint, are included > in landscape mode. The reader's rotate button doesn't help, 'cos it > rotates every page. The solution is to publish documents with all pages > portrait and draw the tables across the page. > > This is 'totally' driving me bonkers, and is why I keep clogging up the > useful discourse on CAF with these ridiculous posts. > It may be off-topic for this newsgroup, but I have certainly learned enough from your posts over the years to be happy to try to help - if I can. > If you don't see this effect, please, for God's sake, put me out of my > misery, and let me know what you did. > I've figured it out - you are using "continuous" mode, so that the pdf reader is looking at the document as though it were one very tall page, and thus fit-width applies to the this whole continuous page. I prefer "single page" mode, in which fit-width (and fit-page) apply to a single page at a time. Hope that helps, David. > Thanks, Syms. > > p.s. A similar thing happens in my old version 7 Adobe viewer, but only > after the viewer has 'seen' a landscape page.Article: 145873
On 2/26/2010 12:58 PM, David Brown wrote: > > I've figured it out - you are using "continuous" mode, so that the pdf > reader is looking at the document as though it were one very tall page, > and thus fit-width applies to the this whole continuous page. I prefer > "single page" mode, in which fit-width (and fit-page) apply to a single > page at a time. > > Hope that helps, > > David. David, you've solved it! I tried going into single page mode before, but I didn't re-click the fit-width thing. Cheers! p.s. I still maintain Altera are wrong to have landscape pages mixed in! I like continuous mode.Article: 145874
On Feb 26, 7:43=A0am, Symon <symon_bre...@hotmail.com> wrote: > It would be impossible for a vendor to publish a 'rise time' for these > devices, because of the many different settings, which is why the IBIS > files are great. Why would it be "impossible" to publish rise time data for parts? They publish delay information for all the various parts with modifiers for the IO standards. Heck, I bet the rise time data is easier since it is likely the same across speed grades and parts. It may vary with package, so it is a wash. The IBIS files are only great if you have a way of simulating them. Oh, the vendors could also provide the *SAME* data in a spice file, not the high accuracy, design detail revealing spice models that they consider proprietary, but models derived from the IBIS descriptions which reveal nothing about your parts the IBIS files don't. I think this is one of those areas where vendors just don't listen well enough to their customers to meet their needs. They see spice models as "bad" because they don't want their IO "secrets" revealed and don't get that a spice model is so much better for the users than IBIS models. Or better yet, go ahead and provide some basic data when requested. Jeeze, these guys actually suggested for me to pull the data from the 80 kB IBIS file with all its cryptic notation and put it in a spread sheet!!! Rick
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