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On Thu, 02 Feb 2006 11:48:10 -0800, Austin Lesea <austin@xilinx.com> wrote: >The most famous (and true) story of this was with the SF Bay Area Rapid >Transit System (BART), in ~1974 or was it 1975?: I was there in '70 or '71: I remember that the line and stations were finished, but there was some technical problem that prevented the trains running.Article: 96376
Hi, group I generated a IPIC interface by the Create and Import Peripheral Wizard to access PLB_DDR blockon the PLB bus. I chose the DMA, user logic Master Support mode. And then try to develop my own logic based on the generated files. Here, I have one problem: To write to an address on PLB bus, I need to provide two addresses: IP2IP_Addr which stores the source data and IP2Bus_Addr to which writes the data. Do I need to instantiate a BRAM in the FPGA to provide the source address? What I am not clear is whether the BRAM is compatible the IPIC logic. Or do I have to instantiate another PLB_Bram and then hook it up to the PLB? Are there any other simple method? Thank you for the help. RogerArticle: 96377
Austin Lesea wrote: > ..... > The static magnetic field will force the static electric field to be > confined to the area adjacent to the current flow in the opposite direction. > > ..... Austin, sure you did not really mean that? Static magnetic fields do not affect electric field(s) according to physics. Dimiter ------------------------------------------------------ Dimiter Popoff Transgalactic Instruments http://www.tgi-sci.com ------------------------------------------------------Article: 96378
Hello everyone I am working on a web site and I need your input to help me build a section of it. This is not a sales presentation I just need your input as fellow professionals dealing with the ROHS no lead problem. I am in need of Pictures of your solder joint failures. I need also what caused the error if you know it, if not, I can help you access it. I need these pictures to be only of the solder joint area with no proprietary items shown in the picture. I need them to be non copy written meaning that you took them, you own them, and you are transferring ownership to me and certifying that the pictures taken are originals and that you are licensing me to use them. I will need information on the process you used and the type of solder and flux chemistry you used. Also in most cases the PCB material (Ie..FR4, IS410 ETC...) Board plating also can help and inf. on the component finish will help me also. I am building a database of problems and solutions using different solder mixtures and profiles. This will help our community of engineers to have one more comprehensive resource of shared knowledge. Please send to: Dolbowent@sbcglobal.netArticle: 96379
Hello everyone I am working on a web site and I need your input to help me build a section of it. This is not a sales presentation I just need your input as fellow professionals dealing with the ROHS no lead problem. I am in need of Pictures of your solder joint failures. I need also what caused the error if you know it, if not, I can help you access it. I need these pictures to be only of the solder joint area with no proprietary items shown in the picture. I need them to be non copy written meaning that you took them, you own them, and you are transferring ownership to me and certifying that the pictures taken are originals and that you are licensing me to use them. I will need information on the process you used and the type of solder and flux chemistry you used. Also in most cases the PCB material (Ie..FR4, IS410 ETC...) Board plating also can help and inf. on the component finish will help me also. I am building a database of problems and solutions using different solder mixtures and profiles. This will help our community of engineers to have one more comprehensive resource of shared knowledge. Please send to: Dolbowent@sbcglobal.netArticle: 96380
dp, Perhaps these folks say it better: "Proximity Effect" As true at DC as at any frequency http://www.cda.org.uk/Megab2/elecapps/pub22/sec4.htm#Proximity%20Effect Commonly misunderstood. You tell me what is happening? I say the DC magnetic field affects current flow. Austin dp wrote: > Austin Lesea wrote: > >>..... >>The static magnetic field will force the static electric field to be >>confined to the area adjacent to the current flow in the opposite direction. >> >>..... > > > Austin, > > sure you did not really mean that? Static magnetic fields do not > affect electric field(s) according to physics. > > Dimiter > > ------------------------------------------------------ > Dimiter Popoff Transgalactic Instruments > > http://www.tgi-sci.com > ------------------------------------------------------ >Article: 96381
In fact, This link is also confused. They talk about ferrous vs non ferrous, and skin effect, too. The basic effect has nothing to do with ferrous or skin effects. austin austin wrote: > dp, > > Perhaps these folks say it better: > > "Proximity Effect" As true at DC as at any frequency > > http://www.cda.org.uk/Megab2/elecapps/pub22/sec4.htm#Proximity%20Effect > > Commonly misunderstood. > > You tell me what is happening? > > I say the DC magnetic field affects current flow. > > Austin > > dp wrote: > >> Austin Lesea wrote: >> >>> ..... >>> The static magnetic field will force the static electric field to be >>> confined to the area adjacent to the current flow in the opposite >>> direction. >>> >>> ..... >> >> >> >> Austin, >> >> sure you did not really mean that? Static magnetic fields do not >> affect electric field(s) according to physics. >> >> Dimiter >> >> ------------------------------------------------------ >> Dimiter Popoff Transgalactic Instruments >> >> http://www.tgi-sci.com >> ------------------------------------------------------ >>Article: 96382
Further, Anyone who can point to a clear and simple explanation, please do. When I first mentioned this to our packaging group, the lead engineer said "oh yes, I see this in the EM simulations..." So, I know I am not imagining it! AustinArticle: 96383
spammersarevermin <spammersarevermin@krumpli.com> wrote: >Is there any way for a hobbyist to obtain the EDK in order to work w/ >Microblaze? Or is there any other way to obtain Microblaze? Order a "Spartan-3E Starter Kit" when they become available. The EDK evaluation is included. This link should work: http://www.xilinx.com/xlnx/xebiz/designResources/ip_product_details.jsp?key=HW-SPAR3E-DK But I'm getting a "techinical difficulties" page. -- Phil HaysArticle: 96384
austin wrote: > Further, > > Anyone who can point to a clear and simple explanation, please do. > > When I first mentioned this to our packaging group, the lead engineer > said "oh yes, I see this in the EM simulations..." > > So, I know I am not imagining it! > > Austin Austin, the only way a simulator can see DC current resulting from a static magnetic field is a software bug or, worse, misconcepted basics behind the software. If physics would allow that we would have unlimited energy for free... just put a magnet next to a conductor and off you go... :-) Perhaps you meant moving (mechanically) a static magnetic field relative to some conductors? This would of course do the job. Dimiter ------------------------------------------------------ Dimiter Popoff Transgalactic Instruments http://www.tgi-sci.com ------------------------------------------------------Article: 96385
dp, I know you do not belive me. And you haven't ever solved Maxwells equations for this case (or else you would see it). I am not going to convince you, so I will not try, but it is a real effect, and it really happens. I also admit that it is greatly misunderstood (after all, Westinghouse believed as you do, util they made a million dollar mistake by building it, and experiencing it first hand). Austin dp wrote: > austin wrote: > >>Further, >> >>Anyone who can point to a clear and simple explanation, please do. >> >>When I first mentioned this to our packaging group, the lead engineer >>said "oh yes, I see this in the EM simulations..." >> >>So, I know I am not imagining it! >> >>Austin > > > Austin, > > the only way a simulator can see DC current > resulting from a static magnetic field is a software bug > or, worse, misconcepted basics behind the software. > If physics would allow that we would have unlimited > energy for free... just put a magnet next to a conductor > and off you go... :-) > > Perhaps you meant moving (mechanically) a static magnetic > field relative to some conductors? This would of course > do the job. > > Dimiter > > ------------------------------------------------------ > Dimiter Popoff Transgalactic Instruments > > http://www.tgi-sci.com > ------------------------------------------------------ >Article: 96386
austin wrote: > dp, > > I know you do not belive me. And you haven't ever solved Maxwells > equations for this case (or else you would see it). > Austin, I also think it is some kind of misunderstanding, of course. Perhaps (if you refer to the railroad story) the motion came from the train moving, or something else they just did not take into account initially, things like that do happen. However, for the case of the BGA socket, this cannot apply. If there is no DC current through the central pads it can only be because of higher active resistance or, more likely, because there is little if any (leakage only, I guess) DC current to talk about. Come to think of it, it should be that last one. BTW, my (1.27 mm pitched) BGA designs all have a via hole in the center of each pad, this is OK if you run small quantities. The most important drawback is the necessity to once fry the BGA chips belly up with some flux, before you use them on the board, lest some of the balls get detached (come coldly soldered from chip vendor) and flow through the board forming a bubble .... (I had this several times until I figured out how to deal with the problem). The most important advantage is obviously having access to all the BGA pads with the scope etc. Dimiter ------------------------------------------------------ Dimiter Popoff Transgalactic Instruments http://www.tgi-sci.com ------------------------------------------------------Article: 96387
austin wrote: > dp, > > I know you do not belive me. And you haven't ever solved Maxwells > equations for this case (or else you would see it). > > I am not going to convince you, so I will not try, but it is a real > effect, and it really happens. > > I also admit that it is greatly misunderstood (after all, Westinghouse > believed as you do, util they made a million dollar mistake by building > it, and experiencing it first hand). Take a magnet near the front of a Shadow mask CRT, and you can clearly see the effect a magnet has on moving (dc) electrons. DC current requires electrons to move, even if the ammeter does not. -jgArticle: 96388
dp, As I said, you do not believe me. Go run the simulation for a 6X6 array. The outer wall of 6 is + (6+6+3+4, the perimeter), and all the inner 5X5 (25 conductors) are -. Then look at the distribution of current at DC. I did find one article on furnaces, which showed the proximity effect on carbon electrodes, but it also made mention of frequency effects, and seemed unclear on what they saw. They clearly saw what I describe in the plots of current. But, they also attributed it to the 50 Hz AC field (which is pretty absurd....skin effect at 50 Hz is negligable!). As I said, well misunderstood. Even after looking at the answer, they explained it wrongly. Austin dp wrote: > austin wrote: > >>dp, >> >>I know you do not belive me. And you haven't ever solved Maxwells >>equations for this case (or else you would see it). >> > > > Austin, > I also think it is some kind of misunderstanding, of course. > > Perhaps (if you refer to the railroad story) the motion came > from the train moving, or something else they just did > not take into account initially, things like that do happen. > > However, for the case of the BGA socket, this cannot > apply. If there is no DC current through the central pads > it can only be because of higher active resistance or, > more likely, because there is little if any (leakage only, > I guess) DC current to talk about. Come to think of it, > it should be that last one. > > BTW, my (1.27 mm pitched) BGA designs all have a > via hole in the center of each pad, this is OK if you run > small quantities. > The most important drawback is the necessity to once > fry the BGA chips belly up with some flux, before you use > them on the board, lest some of the balls get detached > (come coldly soldered from chip vendor) and flow through > the board forming a bubble .... (I had this several times until > I figured out how to deal with the problem). > The most important advantage is obviously having access > to all the BGA pads with the scope etc. > > Dimiter > > ------------------------------------------------------ > Dimiter Popoff Transgalactic Instruments > > http://www.tgi-sci.com > ------------------------------------------------------ >Article: 96389
Jim Granville wrote: > austin wrote: > > dp, > > > > I know you do not belive me. And you haven't ever solved Maxwells > > equations for this case (or else you would see it). > > > > I am not going to convince you, so I will not try, but it is a real > > effect, and it really happens. > > > > I also admit that it is greatly misunderstood (after all, Westinghouse > > believed as you do, util they made a million dollar mistake by building > > it, and experiencing it first hand). > > Take a magnet near the front of a Shadow mask CRT, and you can > clearly see the effect a magnet has on moving (dc) electrons. > DC current requires electrons to move, even if the ammeter does not. > > -jg High school physics is sufficient to know you can deflect the beam of electrons because of the two interacting magnetic fields, the one the electrons produce when moving with the one you apply with your magnet. The DC current value remains unchanged, I hope you are aware of that. Dimiter ------------------------------------------------------ Dimiter Popoff Transgalactic Instruments http://www.tgi-sci.com ------------------------------------------------------Article: 96390
austin wrote: > dp, > > As I said, you do not believe me. > > Go run the simulation for a 6X6 array. > > The outer wall of 6 is + (6+6+3+4, the perimeter), and all the inner 5X5 > (25 conductors) are -. > > Then look at the distribution of current at DC. > > I did find one article on furnaces, which showed the proximity effect on > carbon electrodes, but it also made mention of frequency effects, and > seemed unclear on what they saw. They clearly saw what I describe in > the plots of current. But, they also attributed it to the 50 Hz AC > field (which is pretty absurd....skin effect at 50 Hz is negligable!). > > As I said, well misunderstood. Even after looking at the answer, they > explained it wrongly. > > Austin > > dp wrote: > > > austin wrote: > > > >>dp, > >> > >>I know you do not belive me. And you haven't ever solved Maxwells > >>equations for this case (or else you would see it). > >> > > > > > > Austin, > > I also think it is some kind of misunderstanding, of course. > > > > Perhaps (if you refer to the railroad story) the motion came > > from the train moving, or something else they just did > > not take into account initially, things like that do happen. > > > > However, for the case of the BGA socket, this cannot > > apply. If there is no DC current through the central pads > > it can only be because of higher active resistance or, > > more likely, because there is little if any (leakage only, > > I guess) DC current to talk about. Come to think of it, > > it should be that last one. > > > > BTW, my (1.27 mm pitched) BGA designs all have a > > via hole in the center of each pad, this is OK if you run > > small quantities. > > The most important drawback is the necessity to once > > fry the BGA chips belly up with some flux, before you use > > them on the board, lest some of the balls get detached > > (come coldly soldered from chip vendor) and flow through > > the board forming a bubble .... (I had this several times until > > I figured out how to deal with the problem). > > The most important advantage is obviously having access > > to all the BGA pads with the scope etc. > > > > Dimiter > > > > ------------------------------------------------------ > > Dimiter Popoff Transgalactic Instruments > > > > http://www.tgi-sci.com > > ------------------------------------------------------ > > Austin, I do believe you know what you are talking about. I just do not accept the explanation - physics, as we know it, says it must be different. I am pretty sure you don't just assume there is little, if any DC current flowing through the central BGA pads, you know it is so. It just cannot be explained by any static magnetic field, that's all. My assumption is that there just is no DC current, it can be measured as DC once it has been summed up in the power/ground plane capacitance, decoupling capacitors etc. With CMOS chips, you actually have only leakage DC current, which is orders of magnitude lower than what I believe we are talking about. The rest is only AC. Dimiter ------------------------------------------------------ Dimiter Popoff Transgalactic Instruments http://www.tgi-sci.com ------------------------------------------------------Article: 96391
On Thu, 02 Feb 2006 18:19:26 -0800, Phil Hays blurted: >spammersarevermin <spammersarevermin@krumpli.com> wrote: > >>Is there any way for a hobbyist to obtain the EDK in order to work w/ >>Microblaze? Or is there any other way to obtain Microblaze? > >Order a "Spartan-3E Starter Kit" when they become available. The EDK >evaluation is included. > >This link should work: > >http://www.xilinx.com/xlnx/xebiz/designResources/ip_product_details.jsp?key=HW-SPAR3E-DK > > >But I'm getting a "techinical difficulties" page. Thanks, I bought a Spartan3 starter kit several months ago but couldn't load the bundled software because it bluescreened by development box. So I installed 7.1i. Didn't even realize the the EDK was part of the starter kit. Tom Spamming this account signifies your unqualified consent to a free security auditArticle: 96392
On Thu, 02 Feb 2006 18:19:26 -0800, Phil Hays blurted:
>spammersarevermin <spammersarevermin@krumpli.com> wrote:
>
>>Is there any way for a hobbyist to obtain the EDK in order to work w/
>>Microblaze? Or is there any other way to obtain Microblaze?
>
>Order a "Spartan-3E Starter Kit" when they become available. The EDK
^^ Sorry, parsed this as 3, not 3E
>evaluation is included.
>
>This link should work:
>
>http://www.xilinx.com/xlnx/xebiz/designResources/ip_product_details.jsp?key=HW-SPAR3E-DK
>
>
>But I'm getting a "techinical difficulties" page.
It's still a shame that Microblaze costs $500.
Now I'm done whining.
Thanks, Tom
Spamming this account signifies
your unqualified consent to a free security audit
Article: 96393Austin did not claim that the current changes, just that it takes a different path. I look at it this way: Everything else being equal, the dc current would take the path that puts the least energy into the magnetic field. In other words, it minimizes the rea of the current loop. But opposing that is the resistive drop if all current were to use the smallest loop. So the current finds the right balance. Nature is smart, and consistent. Peter AlfkeArticle: 96394
spammersarevermin wrote: > Is there any way for a hobbyist to obtain the EDK in order to work w/ > Microblaze? Or is there any other way to obtain Microblaze? I don't > have the experience to be able to go to opencores and dive into one of > the processors there. What's so special about microblaze for a hobbyist project? That it's presented as turn-key? The open cores projects, or rolling your own, may have a steeper learning curve, but as a hobbyist you trade a willingess to consider that for an unwillingness to pay what a commercial customer might. If you want to get a task accomplished, buy microblaze or more likely use a common microcontroller either on its own or with a small fpga. If you want to learn something, get the biggest FPGA eval board you can afford and either write your own processor, or adapt one of the open cores projects to it.Article: 96395
Jeff, I experienced some of this same quirkiness with a shared DSOCM BRAM and could'nt pin down the cause. This non-determinism led me to use a shared PLB BRAM, where I experienced no such problems. If your system requirements will allow it, I would switch to using the PLB bus since there isn't much documentation out there on using cooperating PPCs, let alone via sharing a DSOCM BRAM. On the other hand, if you figure out what is going on, I'd love to hear about it! Good luck, JoeyArticle: 96396
Thanks Joey, I'll definitely keep everybody up to date if I get this working. Xilinx support keeps sidestepping the issue. I already have shared memory across the PLB working with no problems, but it's kinda slow. I'd much rather use the 3-cycle OCM instead. It just seems like such an obvious way to connect the two processors. Of course, if I have to implement a lock in the PLB BRAM to get the OCM BRAM to share properly, that might negate much of the performance advantage of using the OCM in the first place. Jeff "Joseph" <joeylrios@gmail.com> wrote in message news:1138951712.444434.71790@g14g2000cwa.googlegroups.com... > Jeff, > > I experienced some of this same quirkiness with a shared DSOCM BRAM and > could'nt pin down the cause. This non-determinism led me to use a > shared PLB BRAM, where I experienced no such problems. If your system > requirements will allow it, I would switch to using the PLB bus since > there isn't much documentation out there on using cooperating PPCs, let > alone via sharing a DSOCM BRAM. On the other hand, if you figure out > what is going on, I'd love to hear about it! > > Good luck, > Joey >Article: 96397
The link doesn't work because someone at Xilinx screwed up.. pardon my Danish... http://www.xilinx.com/xlnx/xebiz/designResources/ip_product_details.jsp?key=HW-SPAR3E-SK-UK You might find what you want here. The EDK has only a 6 month license.. I don't know if it will remain operational after that. If it doesn't, then an Altera NOS II might be a better bet as the license is one year, and the only restriction is you can't produce any commercial product. Simon "Phil Hays" <Spampostmaster@comcast.net> wrote in message news:7ve5u1lm9a22r06urhoatqqkm5v5b4ad9v@4ax.com... > spammersarevermin <spammersarevermin@krumpli.com> wrote: > > >Is there any way for a hobbyist to obtain the EDK in order to work w/ > >Microblaze? Or is there any other way to obtain Microblaze? > > Order a "Spartan-3E Starter Kit" when they become available. The EDK > evaluation is included. > > This link should work: > > http://www.xilinx.com/xlnx/xebiz/designResources/ip_product_details.jsp?key=HW-SPAR3E-DK > > > But I'm getting a "techinical difficulties" page. > > > -- > Phil Hays >Article: 96398
I have been searching around online for a good comparison of the growth rates of FPGAs and ASICs (specifically gate size, power consumption per gate, cost per gate, and clock speed). I am trying to show the gap narrowing between these two over time. I have yet to find any good information, and even raw data would be very useful. Is there any such comparison anyone has seen? If not, does anyone know of a good place to find this type of raw data and historical pricing for FPGAs? I seem to be completely unable to find ASIC equivalent gate ratings for most FPGAs. Thanks in advance.Article: 96399
dp ha escrito: > > I am pretty sure you don't just assume there is little, > if any DC current flowing through the central BGA pads, > you know it is so. It just cannot be explained by any > static magnetic field, that's all. My assumption > is that there just is no DC current, it can be measured > as DC once it has been summed up in the power/ground > plane capacitance, decoupling capacitors etc. With CMOS > chips, you actually have only leakage DC current, which > is orders of magnitude lower than what I believe we are > talking about. The rest is only AC. > I think that you are calling AC current to what actually is Switching current, but CMOS transistors switching current is DC. Try to add a DC ammeter in the VCCAUX and you will see several hundreds of mA. That's why you need a large DC voltage regulator. The result is that there is a large DC current flowing through the central BGA pads as well as some AC current (that originates from changes in the DC current value).
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