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Jeremy Stringer wrote: > I'm starting a new project at the moment, and I'm looking at upgrading > to ISE 7.1, since I prefer not to change synth/par tool versions > mid-project. I noted that a number of people complained about 7.1 when > it first came out, but also noted that Service Pack 2 is out now. Can > anybody comment on the state of ISE 7.1 at the moment? Howdy Jeremy, I don't use Linux, but Windoze based 7.1i has stablized enough that chances are slim you'd run into any problems with it - and even if you do, they are likely fixed in SP3 (due out in the next week or so). Have fun, MarcArticle: 86001
"John Williams" <jwilliams@itee.uq.edu.au> wrote in message news:newscache$n3rcii$ue51ドル@lbox.itee.uq.edu.au... > Hi Marco, > > Marco wrote: > >> I must create a memory for a display lcd. This is part of a >> microcontroller >> based on microblaze. >> >> I thought to do it using a variable, a matrix: display[X][Y] (the >> software >> video memory). >> >> In this way, working with my variable I could edit hardware video memory. >> >> But I'm not able... how may I do it? > > #define HEIGHT ... > #define WIDTH ... > > unsigned char *display[HEIGHT][WIDTH] = (unsigned char *)0x77200000; > > display[y][x] = ... > > Regards, > > John I have tried using what you told me, but during compilation, I receive the following error message: invalid initialize What could I do? Many Thanks MarcoArticle: 86002
Marco wrote: > "John Williams" <jwilliams@itee.uq.edu.au> wrote in message > news:newscache$n3rcii$ue51ドル@lbox.itee.uq.edu.au... > >>#define HEIGHT ... >>#define WIDTH ... >> >>unsigned char *display[HEIGHT][WIDTH] = (unsigned char *)0x77200000; >> >>display[y][x] = ... >> >>Regards, >> >>John > > > I have tried using what you told me, but during compilation, I receive the > following error message: > > invalid initialize > > What could I do? > > Many Thanks > Marco > > Try unsigned char *display[HEIGHT*WIDTH] = (unsigned char *)0x77200000; display[y*WIDTH+x] = I think display[][] is a pointer to a list of pointers: char **, but that's not what you want. If your WIDTH is a power of 2, use shifts instead of y*width. HTH, JanArticle: 86003
Hi all, I implemented a fir filter using the MacFir5.0 core from Xilinx. The filter 2 coefficient sets of 33 taps, with 14 bit coefficients and data. I was looking at the resouces utilization and I found a strange data, the filter requires 33 multipliers and 33 block ram. I can't understand why it requires so much block rams! Each block ram should store 1k x 18bits! If I set the core to use the distributed ram for coefficients or for data this number doesn't change, of course it goes to zero when I set the core to use the distributed ram for both coefficients and data. I read on the User Guide that multipliers and block ram shares routing resources, is that the cause of the great number of bram used?Article: 86004
hi, we've got some Stratix DSP development kit EP1S25 where at the power-on don't load the flash memory to the FPGA !!! We've seen that the EPLD MAX 7064 often fail the programmation of the FPGA... We've seen that the RESET of this EPLD is in the same time that the 3.3 V power-on... Did someone have this this problem yet... and how to boot at any time on power-on ? Perhaps it's be better if the RESET is after the 3.3V power-on ? We utilizes 3 board in a big system and we have this problem now of non programming at boot.. ThanksArticle: 86005
I already have the Spartan3 board and as I can tell from your reply, I should be able to do something challeging and usefull once I get the Ethernet add-on. Thanks, *** Alfredo.Article: 86006
I'm looking for recommended practices for tuning my FPGA design. Merly cranking up the constraints and eyeballing the TA output doesn't seem to work very well for non-trivial problems (I find it very hard to relate back to my RTL). Presumedly the better approach is to work on submodules though timing estimates for individual modules are highly likely to be too optimistic as they do not account for inter-module connections and competition for resources. I vaguely remember reading about in a Xilinx app note how they had two versions of a particular module (an SDRAM controller?), one for real use and one for estimating the performance. The difference IIRC was that input and output were registered. Any suggestions? Thanks, Tommy -- fpga at numba-tu dot comArticle: 86007
"Tommy Thorn" <foobar@nowhere.void> wrote in message news:3ZAte.1390$p%3.10763@typhoon.sonic.net... > I'm looking for recommended practices for tuning my FPGA design. Merly > cranking up the constraints and eyeballing the TA output doesn't seem to > work very well for non-trivial problems (I find it very hard to relate > back to my RTL). > Tommy, Well, that's the way I normally do it. Look at the paths that fail in the TA and then pipeline the paths. After a while you learn to pipline everything anyway, the FFs are free and don't use that much power. I guess this doesn't really help, but there you go! Cheers, Syms.Article: 86008
If you haven't already, check out PlanAhead: http://www.xilinx.com/ise/optional_prod/planahead.htm Tommy Thorn wrote: > > I'm looking for recommended practices for tuning my FPGA design. Merly > cranking up the constraints and eyeballing the TA output doesn't seem to > work very well for non-trivial problems (I find it very hard to relate > back to my RTL). > > Presumedly the better approach is to work on submodules though timing > estimates for individual modules are highly likely to be too optimistic > as they do not account for inter-module connections and competition for > resources. > > I vaguely remember reading about in a Xilinx app note how they had two > versions of a particular module (an SDRAM controller?), one for real use > and one for estimating the performance. The difference IIRC was that > input and output were registered. > > Any suggestions? > > Thanks, > Tommy -- fpga at numba-tu dot comArticle: 86009
have set the respective timing constraints? ispLEVER P&R tool is a timing driven tool. rgds, c Jedi wrote: > Hello.. > > Is this normal that same core which performs well > for Altera Cyclone device can only run at half speed > on a LFEC20-5 device? > > Tried with several CPU cores from opencores.org > and LAttice LFEC20 shows mostly half the performance > as Cyclone... > > > rickArticle: 86010
As promised last week, Xilinx Spartan-3 FPGAs (XC3S50 through XC3S400) are back on the Xilinx online store and in stock. http://www.xilinx.com/store My apologies for any inconvenience that this might have caused. The devices available online are all from the new 300 mm wafer production line. The change-over caused a momentary hiccup in the store data base. --------------------------------- Steven K. Knapp Applications Manager, Xilinx Inc. General Products Division Spartan-3/-3E FPGAs http://www.xilinx.com/spartan3e --------------------------------- The Spartan(tm)-3 Generation: The World's Lowest-Cost FPGAs.Article: 86011
On 2005年6月19日 21:43:20 -0700, "Jon Harris" <jon_harrisTIGER@hotmail.com> wrote: >"Anton Erasmus" <nobody@spam.prevent.net> wrote in message >news:1119169974.ea68157269af093d1f453f607f949e3c@teranews... >> On 2005年6月19日 00:57:12 -0700, "Jon Harris" >> <jon_harrisTIGER@hotmail.com> wrote: >> >> >> "Anton Erasmus" <nobody@spam.prevent.net> wrote in message >> >> news:1119000420.d54828b53b9bcd51f76b2b5b640103a6@teranews... >> >> >> [Snipped] >> >> Yes one would need a sensor with a low noise floor. The lower the >> better. AFAIK the more pixels they pack into a sensor, the higher the >> noise floor. Currently the whole emphasis is on producing sensors with >> more pixels. If the emphasis was on producing sensors with very low >> noise floor, I am sure a suitable sensor can be developed. > >Yes, if you only required, say a 1MP image, this would certainly help, both in >terms of noise and ability to read out the data quickly. > 1MP is quite adequite for a postcard size image or for a newspaper photo. I think there is at least a niche market for a 1MP digital camera that can take a photo without flash that is not blurred in conditions where other cameras would produce a blurred photo. If the sensor technology keeps improving as it had over the last 5 years or so, then the 1MP would go up to 3 or 5MP quite quickly. Regards Anton ErasmusArticle: 86012
"Patrick" <patrick.melet@dmradiocom.fr> schrieb im Newsbeitrag news:54b3002.0506200605.3dadb7cc@posting.google.com... > Perhaps it's be better if the RESET is after the 3.3V power-on ? Use a voltage monitor that releases the reset after ALL voltages are valid. Regards FalkArticle: 86013
cas7406@yahoo.com wrote: > have set the respective timing constraints? ispLEVER P&R tool is a > timing driven tool. > No...as I don't see the point in doing so when under default settings Lattice LFEC is at least 50 % slower... rickArticle: 86014
Guys, I'm trying to compare Altera, Xilinx and Lattice tools (free version) Can Xilinx, Altera and Lattice supporters comment? I found: Lattice starter has included Leonardo/Precision RTL and Synplify, no ModelSim Xilinx ISE WebPack : XST, no Leonardo/Precision, no Synplify, no ModelSim Altera QuartusII Web Edition: support for Synplify, Precision and Modelsim? I know it's a simple comparison, but I would like to be clear on this. Best regards, LucArticle: 86015
"Luc" <lb.edc@pandora.be> schrieb im Newsbeitrag news:kn4eb1p4g60qn0pvpkgamknj6q2nlt2e3p@4ax.com... > Guys, > > I'm trying to compare Altera, Xilinx and Lattice tools (free version) > Can Xilinx, Altera and Lattice supporters comment? > I found: > Lattice starter has included Leonardo/Precision RTL and Synplify, no > ModelSim > Xilinx ISE WebPack : XST, no Leonardo/Precision, no Synplify, no > ModelSim For Xilinx, Modelsim comes in a seperate module, but its also free (AFAIK full simulation speed up to 10000 VHDL lines, wow) Regards FalkArticle: 86016
Rick, I can't speak for LatticeEC in specific, but I know that some designers tend to write their VHDL very specific for one family. Than it will be hard to get the same performance from another device. I.e. does the compiled design make use of the IO cell? Switching this option of can save quite some time (Clock to Out). Regards, Luc On 2005年6月20日 18:57:31 GMT, Jedi <me@aol.com> wrote: >cas7406@yahoo.com wrote: >> have set the respective timing constraints? ispLEVER P&R tool is a >> timing driven tool. >> > >No...as I don't see the point in doing so when under default >settings Lattice LFEC is at least 50 % slower... > > >rickArticle: 86017
Luc wrote: > Rick, > > I can't speak for LatticeEC in specific, but I know that some > designers tend to write their VHDL very specific for one family. Than > it will be hard to get the same performance from another device. > > I.e. does the compiled design make use of the IO cell? Switching this > option of can save quite some time (Clock to Out). > > Regards, > > Luc Actually I test with an out-of-the-box t80 design... I know that Altera Quartus does some good job in using RAM blocks instead of registers automatically since version 4.1 or 4.2 8and old 2.2 I think) whereas the backend tools in ispLever and Actel Libero don't. A simple comparison would be to use a small binary counter and see how fast they can go... rickArticle: 86018
ISE Webpack is definitly better choice than Altera Web Edition. Web Edition does not generate image files (pof. and sof.). In additional ISE Webpcack has minimal limitations and only big disadvantage is core generator which is not included in the Webpack. It means you can not use Xilinx FIFO, DP RAM,... but anywhere you have PLL (DCM)... Synthisiser XST is also very good and in most case you dont need it Leonardo or Synplify... Free Simulator tool (Xilinx Modelsim ) is also avaiable with ISE Webpack.... In the other words you can do it much more with ISE Webpack... Regards , AmirArticle: 86019
lovesinghal wrote: > If you are not as optimistic about FPGAs as I am sounding, what major > bottlenecks do you think will check FPGA growth? > > I am starting my PhD in FPGAs (and looking for topics of research!?!) > and thus interested in knowing the future uses of FPGAs. You're basing a PhD on a few guys comments in a newsgroup ? Impressive... Rene -- Ing.Buero R.Tschaggelar - http://www.ibrtses.com & commercial newsgroups - http://www.talkto.netArticle: 86020
Yes. I think we owe a big round of thanks to Peter Alfke and his crew for making this happen. Mike Harrison wrote: > Further to recent discussiuons here, I Just noticed That S3s have appeared in the Xilinx web store. > A few are even shown as in stock....Article: 86021
A big thanks for everyone at Xilinx to make this happen. I can now be comfident in moving forward with my design.Article: 86022
Actually Quartus web edition does allow you to generate programming files, for certain Altera devices. An exact list can be seen here: http://www.altera.com/products/software/products/quartus2web/sof-quarwebmain.html Also there is no limitation to the cores you can use with the free Altera tools.. if you want a RAM you've got it.. if you want a PLL you've got it. The SOPC Builder system integration/bus generation tool is included for free. There is also the Nios II evaluation download that includes a lot of free-IP, and a time-limited (or unlimited-time-but-tethered-to-host) Nios II core for your evaluation. Jesse Kempa Altera jkempa -at- altera --dot-- comArticle: 86023
Luc wrote: > Guys, > > I'm trying to compare Altera, Xilinx and Lattice tools (free version) > Can Xilinx, Altera and Lattice supporters comment? > I found: > Lattice starter has included Leonardo/Precision RTL and Synplify, no > ModelSim > Xilinx ISE WebPack : XST, no Leonardo/Precision, no Synplify, no > ModelSim > Altera QuartusII Web Edition: support for Synplify, Precision and > Modelsim? > > I know it's a simple comparison, but I would like to be clear on this. May I suggest also another approach? Do a comparison of the distributors as well... Here in this country (live abroad now for 3 years ;o) the best support I got was from: - Altera distributor - Actel distributor - Lattice (direct country office) Worst experience with Xilinx distributor...after 2 - 3 years of hearing them always talking that they are better than Altera. At the end the stomach decides as well...and I prefer the distributor who can provide good support/samples...as nowadays most support is forwarded to local FAE's. rickArticle: 86024
> I am starting my PhD in FPGAs (and looking for topics of research!?!) > and thus interested in knowing the future uses of FPGAs. Some well-thought-out responses to the majority of the questions that you've posed can be found in panel sessions or keynote addresses in conferences like FPGA and FPL from the past couple of years. (For some reason, keynote speakers at these conferences just *love* to rattle the "ASIC vs. FPGA" debate.) As a PhD student, you should have access to the speakers' PowerPoint slides through your university ... cheers, Kris
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Compare FPGA features and resources
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