Custom Search
Site Home Archive Home FAQ Home How to search the Archive How to Navigate the Archive
Compare FPGA features and resources
Threads starting:
Authors:A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
GaborSzakacs wrote: > Ronin wrote: >> hi Guys, >> >> I would like to get started in the FPGA world. I intend to use the >> board to perform computations. Hence connectivity to and from the PC >> should be good and via usb. >> >> Am looking for a low cost fpga board with: >> 1. Inbuilt USB >> 2. Good to have - Ethernet port >> >> Can I use low cost Papillon board for this purpose without soldering ( >> if there are any cables to facilitate data transfer )? >> >> Thanks in advance. >> >> Cheers >> > The only suggestion I can make is to look at each of the major FPGA > manufacturers to see if there are any specials on new development > boards. Usually when they are releasing a new FPGA family they heavily > subsidize the dev board price to get new device wins. I've gotten > some great deals from Lattice this way. I seem to recall a recent > announcement from MicroSemi (Actel) about a new FPGA series... > OK found it: IGLOO2 dev kit at $99 http://www.microsemi.com/products/fpga-soc/design-resources/dev-kits/igloo2/igloo2-evaluation-kit#ordering -- GaborArticle: 155526
On 15/07/13 16:39, GaborSzakacs wrote: > IGLOO2 dev kit at $99 > > http://www.microsemi.com/products/fpga-soc/design-resources/dev-kits/igloo2/igloo2-evaluation-kit#ordering Interesting. What's the general opinion about the design toolchain, both on its own and compared to the Xilinx offering? Often the toolchain is just as important as the device itself.Article: 155527
On 7/15/2013 12:44 PM, Tom Gardner wrote: > On 15/07/13 16:39, GaborSzakacs wrote: >> IGLOO2 dev kit at $99 >> >> http://www.microsemi.com/products/fpga-soc/design-resources/dev-kits/igloo2/igloo2-evaluation-kit#ordering >> > > Interesting. > > What's the general opinion about the design toolchain, both > on its own and compared to the Xilinx offering? Often the > toolchain is just as important as the device itself. I don't have any personal experience with the Igloo tools, but I have heard that they aren't so great. On the other hand I have worked with the tools from X, A and L and find them all to be fairly acceptable. One board that wasn't mentioned is the openRISC development board from Orsoc. It has both Ethernet and host/slave USB. http://opencores.org/shop,item,11 They seem to be out of stock at the moment. -- RickArticle: 155528
On 15/07/13 20:20, rickman wrote: > On 7/15/2013 12:44 PM, Tom Gardner wrote: >> On 15/07/13 16:39, GaborSzakacs wrote: >>> IGLOO2 dev kit at $99 >>> >>> http://www.microsemi.com/products/fpga-soc/design-resources/dev-kits/igloo2/igloo2-evaluation-kit#ordering >>> >> >> Interesting. >> >> What's the general opinion about the design toolchain, both >> on its own and compared to the Xilinx offering? Often the >> toolchain is just as important as the device itself. > > I don't have any personal experience with the Igloo tools, but I have heard that they aren't so great. Does that mean an/all of buggy, slow, incomplete, awkward to use, poor synthesis/place/simluation/etc results? > On the other hand I have worked with the tools from X, A and L and find them all to be fairly > acceptable.Article: 155529
Tom Gardner wrote: > On 15/07/13 16:39, GaborSzakacs wrote: >> IGLOO2 dev kit at $99 >> >> http://www.microsemi.com/products/fpga-soc/design-resources/dev-kits/igloo2/igloo2-evaluation-kit#ordering >> > > Interesting. > > What's the general opinion about the design toolchain, both > on its own and compared to the Xilinx offering? Often the > toolchain is just as important as the device itself. > > I also have no experience with the Igloo tools, and I just noticed that after all the fanfare of how big the Igloo2 is with up to 150K LE's, the eval board has a part iwth 10K LE's which is about the same logic density as a really small (next to the smallest) Spartan 6. I thought $99 was too good to be true. One nice thing about the board is the PCIe connection, which can theoretically get data in and out of your PC much faster than Ethernet or USB, although it probably comes at the price of a lot of work on your part, at least if my experience with Xilinx designs is any indication of required effort. -- GaborArticle: 155530
On 7/15/2013 5:14 PM, Tom Gardner wrote: > On 15/07/13 20:20, rickman wrote: >> On 7/15/2013 12:44 PM, Tom Gardner wrote: >>> On 15/07/13 16:39, GaborSzakacs wrote: >>>> IGLOO2 dev kit at $99 >>>> >>>> http://www.microsemi.com/products/fpga-soc/design-resources/dev-kits/igloo2/igloo2-evaluation-kit#ordering >>>> >>>> >>> >>> Interesting. >>> >>> What's the general opinion about the design toolchain, both >>> on its own and compared to the Xilinx offering? Often the >>> toolchain is just as important as the device itself. >> >> I don't have any personal experience with the Igloo tools, but I have >> heard that they aren't so great. > > Does that mean an/all of buggy, slow, incomplete, awkward > to use, poor synthesis/place/simluation/etc results? I don't have details, but I believe the problems included buggy and poor results/hard to get good results. >> On the other hand I have worked with the tools from X, A and L and >> find them all to be fairly >> acceptable. One qualifier to that, I understand the free tools from Xilinx (which is their own synthesis tool, XST) does not support VHDL 2008. So if you are used to writing your code to the newer standard which is supported (at least in part) by nearly all other vendors, you won't be able to easily port your code to the Xilinx free tools. -- RickArticle: 155531
rickman wrote: > On 7/14/2013 12:37 PM, Les Cargill wrote: <snpi> >> Is it? I've only see the Ainol Novo 9 with Firewire built in. I >> suppose that depends on what you mean by "added to". > > I'm saying the makers could include it easily if there was a demand. > Firewire is a specialty interface for high end cameras. I don't think > there is much need for it now that USB 3.0 is standard on new machines. > Could be. It's not there yet. > >>> They don't include it because it is not of interest to tablet or >>> phone users. Ethernet is done over Wifi. So what is missing? >>> >>> >> >> Data collection I/O. Maybe that will evolve to over Wifi, but >> I have yet to see that. Maybe I should do that; I have >> though t about it. But every time I look at it, it costs too much >> unless you get into large retail establishments. And you can >> stand up a desktop to do it, and pull files over Wifi. > > You mean USB? What data are you collecting? Do you have to keep > limiting your replies to bits and pieces rather than explaining > yourself? Exactly what needed connectivity is missing from tablets and > phones? > Audio, video, the like. I've said that multiple times... other stuff you'd need a PCI card for. I have a small harddisk recorder that has ADAT Lightpipe spigots on it - you can record 16 tracks with it. I've produced and recorded several people's albums with it. Then there's video - although that's less problematic because the main ones of those I've seen have SD cards, although I don't know how I'd do a combined live audio/video thing to where the video could fit on an SD card. But last time I tried that, it was with Hi-8. Striped SMPTE to the audio track on the cameras and synced it all back up in post. Never mind all the industrial stuff you used to be able to do with PCs and is now much harder to do with COTS gear. <snip> >>> I can only think you are blind. My purchasing is totally different now. >> >> Yeah - it's back to the Sears Roebuck catalog model. C'mon - this is >> not a difficult concept. > > Ok, you seem to think that dynamic web pages findable by search engines > are no improvement over waiting literally weeks for catalogs to be > mailed out *if* you know about the company to request them from. One of > the very first impacts of the Internet was the elimination of printed > data sheets by PDF files. I remember when web sites started making them > available, semiconductor companies wanted you to register so they could > retain the info they got when you called to ask for a data book. Now > they use incentives to get you to register. > > But you kept current catalogs in a bookshelf. That's the only real difference now - you don't have two tons of paper to pore over. >>> I price shop easily and mostly buy online. Before the Internet it >>> required trips to the local stores just to see what they had and what it >>> cost. I used to get a 10 lb. (4.5 kg) Computer Shopper to try to find >>> bargains. >> >> So make that a disc instead of a printed catalog. Same >> thing. And make it to where you could download a .iso of >> the disk... > > You refuse to accept that the time factor makes a *huge* difference. I > can't tell you how many times I heard "you will have it in 10 to 14 > days" or "two to three weeks" or even longer. That's mail order. > Internet is a very different world with rapid info, online help chat and > interactive information. > But that's why you had the local rep; you could order parts from them directly. They'd sometimes drive them over... <snip> >> The advantages of stuff over the Internet is much more >> subtle. The vast majority of say, Amazon is the giant >> flea market of a million booths. > > You aren't even listening to what I am saying. Actually the In Store > Pickup is strictly an Internet thing. I don't remember anyone doing > that before you could order on the Internet.. actually that's not > correct. Many years ago Sears had "catalog" stores in towns where they > didn't have a regular store. Right. > You ordered from the catalog and they > delivered to the store, two to three weeks later! The Internet turned > this into two to three days if not in stock! > > Agreed. That's what I was driving at. >>> My >>> girlfriend works for one of the medical labs. All of their computers >>> connect by VPN to order and report lab results over the Internet. >>> Otherwise they would need direct phone lines and it would not be nearly >>> as functional or practical. >>> >> >> No doubt. But one for the first things I did for my >> employer in 1994 was to help us use a T1 line for >> the same purpose. > > Which would be impractical for many applications which would require > such high speed lines for every office in the system at a cost of many > thousands if not millions per year. I know, I've priced a T1 line. That > line would then be special purpose not allowing them to access any other > resource. > > No, the T1 went to a PBX and a Cisco router. Worked great. The far end of the PBX path was another big PBX across the continent. I'm sure it cost a couple thousand a month, but before that we were eating up a lot of long distance. >>> I can't believe you don't see how the Internet is transforming the >>> entire world! This will be bigger than the phone or TV in my opinion. >>> >>> >> >> Emphasis "will be". It's been five years out for fifteen years now :) > > Lol, it is here now if you just open your eyes. How long did it take > for the phone or the auto to be universal and pervasive? Some 50 years > or more I think. Probably something like that. > The Internet is not even 20 yet and has already > transformed us all. > > >>>> Enterprise apps are still trench warfare, when they work at all. >>>> >>>>> It is irrelevant if it is used for other purposes >>>>> and the PC revolution BI (before Internet) was nothing compared to >>>>> what >>>>> it is with the Internet. I think it will prove to be bigger than the >>>>> telephone or the TV in terms of impacting our lives. In fact, it is >>>>> well on the way to replacing both. >>>> >>>> It *has* replaced the telephone, but with an almost identical thing. >>>> Those who say it can replace TV are rather missing the point. >>>> >>>> Content development has converged around cable. There are still two >>>> planes of content - DOCSIS and IP. There's still over the air TV, >>>> but is rather limited. >>> >>> Yes, and cable TV will end up the loser with cable companies being >>> Internet providers. But that is a ways off. TV is just so popular that >>> cable TV will be with us for some time yet. >>> >>> >> >> I expect so; yes. The hot thing now is long-form stuff like Mad Men or >> Justified. that's not something that can exist in an an Internet-only >> model. The capitalization doesn't work. > > Can't say, I haven't worried about most TV for some time now. But there > is no reason why cable TV needs to be the distribution method of TV. > Higher speed Internet suffices just fine. The only question is what > economic model to use and that can be the same as used for cable. > It might be; that remains to be seen. The people who own the content aren't that interested in "over the Internet" though. <snip> >> >> Sensors and actuators. The people I work with build real machines >> that do real work. > > So why couldn't you get a data sheet off their web site? I am sure the > sales person wanted to meet you, but that is still no reason to require > you to get a piece of paper rather than a PDF. The last time I asked > for a data sheet on paper they sales person has to use his printer. I > stopped asking after that. > > Lol! That's pretty good. No, these guys were not set up for that. I was rather shocked myself. I dunno what the story really was; the project engineer just told me to meet with the guy. >>>> Dunno about that - the lappie we use is up in less than a minute. It's >>>> not stored in a cold-down state - it's suspended. >>> >>> Assuming the computer is not in it's bag... If it's not I have to >>> remove it, remove the power pack, plug it in, open the lid and in a few >>> seconds it prompts me for a password, a few more seconds (well a large >>> few) it gives me the UI screen and starts connecting to the Wifi, then a >>> few more seconds and the email program figures out it is connected... >>> all in all it is well over a minute before it is ready for me to use. >>> You just have to pick up the tablet then push a button and swipe a >>> finger across the screen... you're in. HUGE difference. >>> >>> >> >> Wow, mine does none of that. You open the lid, it brings up >> the login and you're done in less than a minute. > > You never have to plug it in? That's pretty good. Atomic power? Nukular. No, it plugs in, but that has nought to do with how long it takes to wake up. > Even > so that is still more than an order of magnitude longer than a tablet. > The tablet is also there when the laptop is not. Do you drag the laptop > with you when you leave the office or house? Only when we're traveling. > Do you take it upstairs > when you go to bed in order to read your novel in bed? Absolutely not. I still use paper books. > Do you take it > on the deck when you want to relax with a glass of iced tea and browse > the web on a break? > Sure. it's easy to use in that way, and there's a keyboard/"mouse". > The difference in size and convenience is very significant. The phones > are still phones first and Internet devices second. But they top the > list in terms of availability. I *always* have my phone with me as do > many. By comparison, the laptop is an albatross in a bag with a > shoulder strap. > I barely even use my phone. And it's a flip, not a smart phone. <snip> >> >> My point is that they don't do anything - beyond post captioned >> cat videos. They're Barbie fashion accessories. > > That is silly and totally inaccurate. You clearly have not seen anyone > actually using them. You won't be able to remain ignorant of them long. > They are popping up everywhere. I am seeing about half as many > tablets as laptops at Panera Bread these days and the numbers are > growing fast. > > Right. Most people don't do much, beyond shop and travel. Hey, if it works for you, then awesome, but it won't cut it for me. <snip> >> We still use brick and mortar for buying food. > > Ah, so you won't go without. > > >>>>>>> and I can have a keyboard with me even more easily than my 17" >>>>>>> laptop. So why wouldn't a tablet with say a 128 GB flash drive >>>>>>> make my >>>>>>> day? Right now the only limitation is the lack of support for >>>>>>> Android >>>>>>> by the FPGA software vendors. I can't imagine that isn't going to >>>>>>> change soon. >>>>>>> >>>>>>> >>>>>> >>>>>> We'll see. I am not sure how much of Linux is missing >>>>>> from Android; other than that it shouldn't be too bad. You will >>>>>> need a big ole screen, though. >>>>> >>>>> Any flat screen TV will be much better than my laptop or desktop. >>>>> >>>>> >>>> >>>> This has its challenges as well. >>> >>> What are you talking about? >>> >> >> >> you have to put a large screen TV on something. if it's more than six >> feet away, you lose any advantage from it being a large screen. > > What? My laptop in my lap is the smaller than the TV (I am planning to > buy) on the wall. The TV has higher resolution. > Oh - I thought you'd meant something else, like using the TV as a monitor. I've thought about that but it doesn't work very well. <snip> >> >> On a *tablet* you do those? No, you have to >> at least have a laptop. > > Which of these can't you do on a tablet? What is your point? How does > a tablet limit what you can do? > Oh my. -- Les CargillArticle: 155532
On 7/15/2013 6:57 PM, Les Cargill wrote: > rickman wrote: >> On 7/14/2013 12:37 PM, Les Cargill wrote: > <snpi> >>> Is it? I've only see the Ainol Novo 9 with Firewire built in. I >>> suppose that depends on what you mean by "added to". >> >> I'm saying the makers could include it easily if there was a demand. >> Firewire is a specialty interface for high end cameras. I don't think >> there is much need for it now that USB 3.0 is standard on new machines. >> > > > Could be. It's not there yet. > >> >>>> They don't include it because it is not of interest to tablet or >>>> phone users. Ethernet is done over Wifi. So what is missing? >>>> >>>> >>> >>> Data collection I/O. Maybe that will evolve to over Wifi, but >>> I have yet to see that. Maybe I should do that; I have >>> though t about it. But every time I look at it, it costs too much >>> unless you get into large retail establishments. And you can >>> stand up a desktop to do it, and pull files over Wifi. >> >> You mean USB? What data are you collecting? Do you have to keep >> limiting your replies to bits and pieces rather than explaining >> yourself? Exactly what needed connectivity is missing from tablets and >> phones? >> > > Audio, video, the like. I've said that multiple times... other stuff > you'd need a PCI card for. Yes, you've *said* it but still not explained it. Every tablet and phone I've ever seen has an earphone jack and mic input. I have no idea why you would need a PCI card for audio I/O. What is lacking in the video outputs of tablets? If you need video input I'm sure there are any number of USB interfaced cameras. I can't imaging how PCI would provide any sort of interface for a camera that you can't do with USB... That's what I mean by you aren't explaining yourself. > I have a small harddisk recorder that has ADAT Lightpipe > spigots on it - you can record 16 tracks with it. I've produced > and recorded several people's albums with it. So? There are any number of highly specialized pieces of equipment that you can't connect to laptops, etc. They are a tiny market compared to the rest of computing. You are talking about niche markets. I'm talking about mainstream. I've already said that PCs won't go away, even desktops will remain for those who want the highest performance at any cost. The rest of us can get on without the cumbersomeness of full sized computers and laptops. > Then there's video - although that's less problematic because > the main ones of those I've seen have SD cards, although I don't > know how I'd do a combined live audio/video thing to where the video > could fit on an SD card. But last time I tried that, it was > with Hi-8. Striped SMPTE to the audio track on the cameras and > synced it all back up in post. > > Never mind all the industrial stuff you used to be able > to do with PCs and is now much harder to do with COTS gear. "All" the industrial stuff? What about it? Again, that is a tiny market compared to the consumer market. The server market is fairly big and they are starting to change over to ARM CPUs to conserve power. I don't know that what they are using is really much like a standard desktop and hasn't been so for a long time. >>>> I can only think you are blind. My purchasing is totally different now. >>> >>> Yeah - it's back to the Sears Roebuck catalog model. C'mon - this is >>> not a difficult concept. >> >> Ok, you seem to think that dynamic web pages findable by search engines >> are no improvement over waiting literally weeks for catalogs to be >> mailed out *if* you know about the company to request them from. One of >> the very first impacts of the Internet was the elimination of printed >> data sheets by PDF files. I remember when web sites started making them >> available, semiconductor companies wanted you to register so they could >> retain the info they got when you called to ask for a data book. Now >> they use incentives to get you to register. >> >> > > But you kept current catalogs in a bookshelf. That's the only real > difference now - you don't have two tons of paper to pore > over. You dismiss the tremendous advantages of having data sheets on the computer. The original data sheet costs so little to publish and updates are nearly free. They are available immediately on the web and you don't need a book, much less a book case to hold them, you just plop them into your portable and they go where ever you go. I guess you are still doing work like you did over 20 years ago. I work very differently now and I design hardware. I am nearly portable with everything I need in my computer bag. I still need to get one of those USB logic analyzers/oscilloscopes and I won't be tied to anything bigger than my laptop. In five years it will be anything bigger than my tablet. >>>> I price shop easily and mostly buy online. Before the Internet it >>>> required trips to the local stores just to see what they had and >>>> what it >>>> cost. I used to get a 10 lb. (4.5 kg) Computer Shopper to try to find >>>> bargains. >>> >>> So make that a disc instead of a printed catalog. Same >>> thing. And make it to where you could download a .iso of >>> the disk... >> >> You refuse to accept that the time factor makes a *huge* difference. I >> can't tell you how many times I heard "you will have it in 10 to 14 >> days" or "two to three weeks" or even longer. That's mail order. >> Internet is a very different world with rapid info, online help chat and >> interactive information. >> > > > But that's why you had the local rep; you could order parts > from them directly. They'd sometimes drive them over... Yep, that was the day. Now they are happy to meet me and deliver stuff, but what do they have to deliver? I'm meeting a vendor tomorrow morning and it will be breakfast and talk... no data sheets, no paper of any kind I expect. >>> The advantages of stuff over the Internet is much more >>> subtle. The vast majority of say, Amazon is the giant >>> flea market of a million booths. >> >> You aren't even listening to what I am saying. Actually the In Store >> Pickup is strictly an Internet thing. I don't remember anyone doing >> that before you could order on the Internet.. actually that's not >> correct. Many years ago Sears had "catalog" stores in towns where they >> didn't have a regular store. > > Right. > >> You ordered from the catalog and they >> delivered to the store, two to three weeks later! The Internet turned >> this into two to three days if not in stock! >> >> > > Agreed. That's what I was driving at. > >>>> My >>>> girlfriend works for one of the medical labs. All of their computers >>>> connect by VPN to order and report lab results over the Internet. >>>> Otherwise they would need direct phone lines and it would not be nearly >>>> as functional or practical. >>>> >>> >>> No doubt. But one for the first things I did for my >>> employer in 1994 was to help us use a T1 line for >>> the same purpose. >> >> Which would be impractical for many applications which would require >> such high speed lines for every office in the system at a cost of many >> thousands if not millions per year. I know, I've priced a T1 line. That >> line would then be special purpose not allowing them to access any other >> resource. >> >> > > No, the T1 went to a PBX and a Cisco router. Worked great. The far end > of the PBX path was another big PBX across the continent. I'm sure it > cost a couple thousand a month, but before that we were eating up a lot > of long distance. I don't know where you are going with this. Are you suggesting that the Internet doesn't make this horribly obsolete and absurd? With the Internet you plug in and you can be connected to everything and everybody in the world! Your T-1 couldn't do that! >>>> I can't believe you don't see how the Internet is transforming the >>>> entire world! This will be bigger than the phone or TV in my opinion. >>>> >>>> >>> >>> Emphasis "will be". It's been five years out for fifteen years now :) >> >> Lol, it is here now if you just open your eyes. How long did it take >> for the phone or the auto to be universal and pervasive? Some 50 years >> or more I think. > > Probably something like that. > >> The Internet is not even 20 yet and has already >> transformed us all. >> >> >>>>> Enterprise apps are still trench warfare, when they work at all. >>>>> >>>>>> It is irrelevant if it is used for other purposes >>>>>> and the PC revolution BI (before Internet) was nothing compared to >>>>>> what >>>>>> it is with the Internet. I think it will prove to be bigger than the >>>>>> telephone or the TV in terms of impacting our lives. In fact, it is >>>>>> well on the way to replacing both. >>>>> >>>>> It *has* replaced the telephone, but with an almost identical thing. >>>>> Those who say it can replace TV are rather missing the point. >>>>> >>>>> Content development has converged around cable. There are still two >>>>> planes of content - DOCSIS and IP. There's still over the air TV, >>>>> but is rather limited. >>>> >>>> Yes, and cable TV will end up the loser with cable companies being >>>> Internet providers. But that is a ways off. TV is just so popular that >>>> cable TV will be with us for some time yet. >>>> >>>> >>> >>> I expect so; yes. The hot thing now is long-form stuff like Mad Men or >>> Justified. that's not something that can exist in an an Internet-only >>> model. The capitalization doesn't work. >> >> Can't say, I haven't worried about most TV for some time now. But there >> is no reason why cable TV needs to be the distribution method of TV. >> Higher speed Internet suffices just fine. The only question is what >> economic model to use and that can be the same as used for cable. >> > > It might be; that remains to be seen. The people who own the > content aren't that interested in "over the Internet" though. I don't know what you are talking about. They don't *understand* the Internet, but they know they have to adapt to it or become the next Blockbuster. I spent a couple of hours the last couple days watching TV on the computer as this is the only way I can watch it. Turns out it works pretty durn well. Same commercial model so the economics are very similar. >>> Sensors and actuators. The people I work with build real machines >>> that do real work. >> >> So why couldn't you get a data sheet off their web site? I am sure the >> sales person wanted to meet you, but that is still no reason to require >> you to get a piece of paper rather than a PDF. The last time I asked >> for a data sheet on paper they sales person has to use his printer. I >> stopped asking after that. >> >> > > Lol! That's pretty good. No, these guys were not set up for that. I > was rather shocked myself. I dunno what the story really was; the > project engineer just told me to meet with the guy. > >>>>> Dunno about that - the lappie we use is up in less than a minute. It's >>>>> not stored in a cold-down state - it's suspended. >>>> >>>> Assuming the computer is not in it's bag... If it's not I have to >>>> remove it, remove the power pack, plug it in, open the lid and in a few >>>> seconds it prompts me for a password, a few more seconds (well a large >>>> few) it gives me the UI screen and starts connecting to the Wifi, >>>> then a >>>> few more seconds and the email program figures out it is connected... >>>> all in all it is well over a minute before it is ready for me to use. >>>> You just have to pick up the tablet then push a button and swipe a >>>> finger across the screen... you're in. HUGE difference. >>>> >>>> >>> >>> Wow, mine does none of that. You open the lid, it brings up >>> the login and you're done in less than a minute. >> >> You never have to plug it in? That's pretty good. Atomic power? > > Nukular. No, it plugs in, but that has nought to do with how long it > takes to wake up. Ok, then you either leave it plugged in at a fixed location or you have to spend time plugging in it each time you fire it up. That is the difference. Tablets and phones are designed to be portable rather than transportable. Big difference. Today's notebooks are just one step away from the Compaq "portable" of the late 80's. >> Even >> so that is still more than an order of magnitude longer than a tablet. >> The tablet is also there when the laptop is not. Do you drag the laptop >> with you when you leave the office or house? > > > Only when we're traveling. That again is my point. The tablet and phone are there with you where ever you go. That makes a HUGE difference to most people. >> Do you take it upstairs >> when you go to bed in order to read your novel in bed? > > Absolutely not. I still use paper books. The e-paper books are actually easier to read than books in my opinion. You don't have to hold them open to a page and I think they have better contrast. Plus, every book is a "large print" edition if I want it to be. >> Do you take it >> on the deck when you want to relax with a glass of iced tea and browse >> the web on a break? >> > > Sure. it's easy to use in that way, and there's a keyboard/"mouse". I find the laptop a bit awkward anywhere I haven't set up for it. It needs a sizable place to sit and I have to move to *it* rather than holding it where I want to be. My girlfriend lounges in a beanbag/wicker chair with her tablet which she could never do with her laptop. >> The difference in size and convenience is very significant. The phones >> are still phones first and Internet devices second. But they top the >> list in terms of availability. I *always* have my phone with me as do >> many. By comparison, the laptop is an albatross in a bag with a >> shoulder strap. >> > > I barely even use my phone. And it's a flip, not a smart phone. Ok, you haven't found the need, but that doesn't mean the market isn't there, you are just an outlier. >>> My point is that they don't do anything - beyond post captioned >>> cat videos. They're Barbie fashion accessories. >> >> That is silly and totally inaccurate. You clearly have not seen anyone >> actually using them. You won't be able to remain ignorant of them long. >> They are popping up everywhere. I am seeing about half as many >> tablets as laptops at Panera Bread these days and the numbers are >> growing fast. >> >> > > Right. Most people don't do much, beyond shop and travel. Hey, if > it works for you, then awesome, but it won't cut it for me. Yes, I can see that. You don't do the things that most people do. >>> We still use brick and mortar for buying food. >> >> Ah, so you won't go without. >> >> >>>>>>>> and I can have a keyboard with me even more easily than my 17" >>>>>>>> laptop. So why wouldn't a tablet with say a 128 GB flash drive >>>>>>>> make my >>>>>>>> day? Right now the only limitation is the lack of support for >>>>>>>> Android >>>>>>>> by the FPGA software vendors. I can't imagine that isn't going to >>>>>>>> change soon. >>>>>>>> >>>>>>>> >>>>>>> >>>>>>> We'll see. I am not sure how much of Linux is missing >>>>>>> from Android; other than that it shouldn't be too bad. You will >>>>>>> need a big ole screen, though. >>>>>> >>>>>> Any flat screen TV will be much better than my laptop or desktop. >>>>>> >>>>>> >>>>> >>>>> This has its challenges as well. >>>> >>>> What are you talking about? >>>> >>> >>> >>> you have to put a large screen TV on something. if it's more than six >>> feet away, you lose any advantage from it being a large screen. >> >> What? My laptop in my lap is the smaller than the TV (I am planning to >> buy) on the wall. The TV has higher resolution. >> > > Oh - I thought you'd meant something else, like using the TV as a > monitor. I've thought about that but it doesn't work very well. I *am* talking about using the TV as a monitor. It will be over my desk as a huge monitor and will swing out a bit so it can be seen from the living room furniture to watch TV. >>> On a *tablet* you do those? No, you have to >>> at least have a laptop. >> >> Which of these can't you do on a tablet? What is your point? How does >> a tablet limit what you can do? >> > > Oh my. I guess this conversation is about over. It is clear that you think the market is based on what you want from computers. It is very much *not* like what you want. Most people prefer to never touch a keyboard. They much prefer to use a touch screen because it is *there* when they need it where ever they are. If you think the market is going to continue to demand more and more desktop and laptop computers you will be surprised over the next few years and PCs are shoved aside by tablets and phones. Even Dell is pushing their tablets now. -- RickArticle: 155533
rickman wrote: > On 7/15/2013 6:57 PM, Les Cargill wrote: <snip> > > I guess this conversation is about over. It is clear that you think the > market is based on what you want from computers. It is very much *not* > like what you want. Most people prefer to never touch a keyboard. They > much prefer to use a touch screen because it is *there* when they need > it where ever they are. If you think the market is going to continue to > demand more and more desktop and laptop computers you will be surprised > over the next few years and PCs are shoved aside by tablets and phones. > Even Dell is pushing their tablets now. > I certainly appreciate your enthusiasm. No offense; I did not intend to inspire exasperation. -- Les CargillArticle: 155534
I have some experience with Actel/Microsemi ProASIC chips, for the applicat= ion I used them for I found them to be much slower than Xilinx or Altera. = They have major benefits, like no need for an external prom because of the = anti fuse ( which I think makes them slower) and if I remember correctly th= ey were quite a bit lower power, at least compared to the stratix and virte= x of that day. I did not have any complaints about the tools, in fact in t= hose days I was using Leonardo to synthesize altera and synplify to synthes= ize Xilinx while the actel chips seemed to get the best results using the a= ctel designer tools, but that was a while ago. Today Xilinx has me confuse= d with all the different tool flows, I tried Vivado and it didn't work well= for me so I am back to ise. I will say that I am happy with the results I = am getting from ise synthesis and don't use synplify anymore. I have not = done a design for altera in five years or so but the last time I did it was= Leo and quartus which was just okay. Personally if I was starting today designing fpga's I would go with the bes= t Xilinx dev kit from a cost/ requirement standpoint and use the ise webpac= k to learn on. Papilio would be a great place to start, a strong user comm= unity with support from the board designer and a forum and even a free star= ters guide. You do need to figure another way to move data between PC and = board but the ftdi USB to uart is one option that makes sense. One other place to get well priced dev kits is digilent, I have been happy = with what I bought from them. =20 Ronin if you are reading these posts are we answering what you need or talk= ing to ourselves? ChrisArticle: 155535
How about digilents basys2? http://www.digilentinc.com/Products/Detail.cfm?NavPath=2,400,790&Prod=BASYS2 $49 for us students, USB data transfers via an onboard atmel microcontroller. No Ethernet but hey it is only $49! ChrisArticle: 155536
On 16/07/13 05:59, Chris wrote: > I have some experience with Actel/Microsemi ProASIC chips, for the > application I used them for I found them to be much slower than Xilinx > or Altera. They have major benefits, like no need for an external > prom because of the anti fuse ( which I think makes them slower) > and if I remember correctly they were quite a bit lower power, at > least compared to the stratix and virtex of that day. I did not > have any complaints about the tools, in fact in those days I was > using Leonardo to synthesize altera and synplify to synthesize > Xilinx while the actel chips seemed to get the best results using the > actel designer tools, but that was a while ago. Today Xilinx has me > confused with all the different tool flows, I tried Vivado and it > didn't work well for me so I am back to ise. I will say that I am > happy with the results I am getting from ise synthesis and don't > use synplify anymore. I have not done a design for altera in five > years or so but the last time I did it was Leo and quartus which > was just okay. Very useful. The toolflow is confusing; I'm hoping a book I've just received will nudge me in the right direction! > Personally if I was starting today designing fpga's I would go > with the best Xilinx dev kit from a cost/ requirement standpoint > and use the ise webpack to learn on. That's what I've been planning, but I know what I don't know. I'm biassed towards Xilinx simply because I used an XC2000 back in the 80s, and knew and liked Wim Roelandts when he was at HP (insider joke: that was before HP was renamed Agilent). > Papilio would be a great place to start, a strong user community with > support from the board designer and a forum and even a free starters guide. > You do need to figure another way to move data between PC and board but > the ftdi USB to uart is one option that makes sense. My primary requirement (almost the only requirement!) is high speed serial interface. I've been looking at the Ztex 1.15b with the highest speed variant of a spartan-6-75 for 239euro. http://www.ztex.de/usb-fpga-1/usb-fpga-1.15.e.html The company has a range of simple useful shields, and has been around long enough to have an "obsolete boards" section. Nonetheless, if anyone else has any observations, I'll listen. > Ronin if you are reading these posts are we answering what you need or talking to ourselves? I can't answer for Ronin, but you and others /are/ helping me.Article: 155537
On Tuesday, July 16, 2013 1:15:09 AM UTC-7, Tom Gardner wrote: > On 16/07/13 05:59, Chris wrote: >=20 > > I have some experience with Actel/Microsemi ProASIC chips, for the >=20 > > application I used them for I found them to be much slower than Xilinx >=20 > > or Altera. They have major benefits, like no need for an external >=20 > > prom because of the anti fuse ( which I think makes them slower) >=20 > > and if I remember correctly they were quite a bit lower power, at >=20 > > least compared to the stratix and virtex of that day.=20 I was looking up some of my old designs and the ProASICs were not antifuse,= just flash based. Again, very useful in that you don't need an external P= ROM for bitstream storage but you pay for it in performance. If I needed t= o push the limits of speed it would not be done with an Actel (/Microsemi).= I would use the Actel/Microsemi solution if I was looking for space savin= gs or lower power... as long as I can convince myself I can still meet my d= esign requirements. I did actually work on an antifuse Actel over 10 years ago, a 54SX series. = Those were hairy, they only programmed once and were in a PQ208 package th= at took FOREVER to put down on a board. We used to cut all of the pins to = remove the device then desolder them pin by pin, if you tried changing it m= ore than once you were guaranteed to rip pads off the board... ahhh the goo= d old days. =20 >=20 > I can't answer for Ronin, but you and others /are/ helping me. Great, thanks for the feedback, I just wanted to check if Ronin was getting= what he wanted out of his question.Article: 155538
On 7/16/2013 4:15 AM, Tom Gardner wrote: > > That's what I've been planning, but I know what I don't know. > > I'm biassed towards Xilinx simply because I used an XC2000 back > in the 80s, and knew and liked Wim Roelandts when he was at HP > (insider joke: that was before HP was renamed Agilent). I didn't work with the XC2000 series, but I did a bit with the 3000. Not so much fun using those tools as today although it was either schematic or manual editing of the part in the chip editor. So should I assume you are actually agnostic about the brand of FPGA? > My primary requirement (almost the only requirement!) is high > speed serial interface. I've been looking at the Ztex 1.15b with the > highest speed variant of a spartan-6-75 for 239euro. > http://www.ztex.de/usb-fpga-1/usb-fpga-1.15.e.html > The company has a range of simple useful shields, and has > been around long enough to have an "obsolete boards" section. I'm not familiar with your use of the terms "high speed serial interface" and "shields". By shields do you mean daughter cards? I think shields is the term used for Arduino daughter cards, I don't normally see it used anywhere else. As to "high speed serial interface" that is a bit broad. Are you talking about an async RS-232 type interface or something more specific like USB high speed or Ethernet? It looks like the ztec board has USB, but that is through the Cypress chip and so isn't directly accessible to the FPGA. What do you want the high speed serial port for? Don't you have any requirements for the FPGA? > Nonetheless, if anyone else has any observations, I'll listen. Certainly if you are willing to spend well over $200 there are lots of boards around. Do you have any other requirements? -- RickArticle: 155539
On 16/07/13 17:00, rickman wrote: > So should I assume you are actually agnostic about the brand of FPGA? Correct. >> My primary requirement (almost the only requirement!) is high >> speed serial interface. I've been looking at the Ztex 1.15b with the >> highest speed variant of a spartan-6-75 for 239euro. >> http://www.ztex.de/usb-fpga-1/usb-fpga-1.15.e.html >> The company has a range of simple useful shields, and has >> been around long enough to have an "obsolete boards" section. > > I'm not familiar with your use of the terms "high speed serial interface" and "shields". By shields do you mean daughter cards? I think shields is the term used for Arduino daughter cards, I don't > normally see it used anywhere else. Yes, I was using it in the arduino sense, e.g. ztec's PSU module. > As to "high speed serial interface" that is a bit broad. Are you talking about an async RS-232 type interface or something more specific like USB high speed or Ethernet? All I want to do is sample the output of a MAX9979 as fast as possible, and then store and process it in fairly simple (albeit high speed) ways. 1GS/s is a good round number. 900M/s wouldn't be bad, but is less sexy :) A stretch goal is to sample at 2GS/s using separate interleaved channels. Looks like the various SERDES i/o structures will be useful, provided I can avoid having any PHY-level encoding. Raw bitstreams only, please :) Getting hold of a MAX9979 without paying 200euro is a separate issue :( > It looks like the ztec board has USB, but that is through the Cypress chip and so isn't directly accessible to the FPGA. Correct. You can also program the Cypress chip yourself if you want an on-board controller that doesn't easily fit into the FPGA. >> Nonetheless, if anyone else has any observations, I'll listen. > > Certainly if you are willing to spend well over $200 there are lots of boards around. Do you have any other requirements? Not really, although a 3+ medium-speed DACs (~1MS/s) might be handy!Article: 155540
On 7/16/2013 12:36 PM, Tom Gardner wrote: > On 16/07/13 17:00, rickman wrote: >> So should I assume you are actually agnostic about the brand of FPGA? > > Correct. > > >>> My primary requirement (almost the only requirement!) is high >>> speed serial interface. I've been looking at the Ztex 1.15b with the >>> highest speed variant of a spartan-6-75 for 239euro. >>> http://www.ztex.de/usb-fpga-1/usb-fpga-1.15.e.html >>> The company has a range of simple useful shields, and has >>> been around long enough to have an "obsolete boards" section. >> >> I'm not familiar with your use of the terms "high speed serial >> interface" and "shields". By shields do you mean daughter cards? I >> think shields is the term used for Arduino daughter cards, I don't >> normally see it used anywhere else. > > Yes, I was using it in the arduino sense, e.g. ztec's PSU > module. > > >> As to "high speed serial interface" that is a bit broad. Are you >> talking about an async RS-232 type interface or something more >> specific like USB high speed or Ethernet? > > All I want to do is sample the output of a MAX9979 as fast as possible, > and then store and process it in fairly simple (albeit high speed) ways. > 1GS/s is a good round number. 900M/s wouldn't be bad, but > is less sexy :) A stretch goal is to sample > at 2GS/s using separate interleaved channels. Looks like the > various SERDES i/o structures will be useful, provided I can > avoid having any PHY-level encoding. Raw bitstreams only, please :) > > Getting hold of a MAX9979 without paying 200euro is a > separate issue :( So the MAX9979 is some sort of buffer chip and you want to sample the output using a SERDES or two? Why didn't you say that? Not all FPGAs have SERDES. I've not worked with them before so I can't tell you which have encoding or not. I do know that Lattice was the first company to add SERDES to their low cost line of FPGAs. Once they did it, X and A had to as well. >> It looks like the ztec board has USB, but that is through the Cypress >> chip and so isn't directly accessible to the FPGA. > > Correct. You can also program the Cypress chip yourself > if you want an on-board controller that doesn't easily > fit into the FPGA. My question is, what do you want from the USB port? >>> Nonetheless, if anyone else has any observations, I'll listen. >> >> Certainly if you are willing to spend well over $200 there are lots of >> boards around. Do you have any other requirements? > > Not really, although a 3+ medium-speed DACs (~1MS/s) might > be handy! That can be done in the FPGA with a few spare pins. How much resolution do you need? -- RickArticle: 155541
On 16/07/13 18:07, rickman wrote: > On 7/16/2013 12:36 PM, Tom Gardner wrote: >> On 16/07/13 17:00, rickman wrote: >>> So should I assume you are actually agnostic about the brand of FPGA? >> >> Correct. >> >> >>>> My primary requirement (almost the only requirement!) is high >>>> speed serial interface. I've been looking at the Ztex 1.15b with the >>>> highest speed variant of a spartan-6-75 for 239euro. >>>> http://www.ztex.de/usb-fpga-1/usb-fpga-1.15.e.html >>>> The company has a range of simple useful shields, and has >>>> been around long enough to have an "obsolete boards" section. >>> >>> I'm not familiar with your use of the terms "high speed serial >>> interface" and "shields". By shields do you mean daughter cards? I >>> think shields is the term used for Arduino daughter cards, I don't >>> normally see it used anywhere else. >> >> Yes, I was using it in the arduino sense, e.g. ztec's PSU >> module. >> >> >>> As to "high speed serial interface" that is a bit broad. Are you >>> talking about an async RS-232 type interface or something more >>> specific like USB high speed or Ethernet? >> >> All I want to do is sample the output of a MAX9979 as fast as possible, >> and then store and process it in fairly simple (albeit high speed) ways. >> 1GS/s is a good round number. 900M/s wouldn't be bad, but >> is less sexy :) A stretch goal is to sample >> at 2GS/s using separate interleaved channels. Looks like the >> various SERDES i/o structures will be useful, provided I can >> avoid having any PHY-level encoding. Raw bitstreams only, please :) >> >> Getting hold of a MAX9979 without paying 200euro is a >> separate issue :( > > So the MAX9979 is some sort of buffer chip and you want to sample the output using a SERDES or two? Why didn't you say that? Because it wasn't important to the original question about the toolchain. > Not all FPGAs have SERDES. I've not worked with them before so I can't > tell you which have encoding or not. I do know that Lattice was the > first company to add SERDES to their low cost line of FPGAs. > Once they did it, X and A had to as well. I can use datasheets to assess FPGAs for my application perfectly well, thank you. I don't, however, have experience in using the current toolchains with all their foibles. >>> Certainly if you are willing to spend well over $200 there are lots of >>> boards around. Do you have any other requirements? >> >> Not really, although a 3+ medium-speed DACs (~1MS/s) might >> be handy! > > That can be done in the FPGA with a few spare pins. How much resolution do you need? Sure can. That's why I didn't bother mentioning it!Article: 155542
It seems that Xilinx is once again abandoning the low-cost high-volume market in pursuit of those lucrative high-end sockets. There latest announcement shows less roadmap as the devices go towards the low end of the price curve: http://www.xilinx.com/products/technology/ultrascale/ -- GaborArticle: 155543
On 7/16/2013 3:20 PM, GaborSzakacs wrote: > It seems that Xilinx is once again abandoning the low-cost > high-volume market in pursuit of those lucrative high-end > sockets. There latest announcement shows less roadmap > as the devices go towards the low end of the price curve: > > http://www.xilinx.com/products/technology/ultrascale/ I didn't listen to the video, but looking at the pictures... (what I do best)... it appears that they are indeed going the route of just one product line. Virtex UltraScale will be the only product in the Xilinx line at the 16 nm node. The question is will having only one device line make a difference? Perhaps this will be a one size (or one process) fits all approach. Is there any reason why they can't make low end devices with a competitive price along with high end devices with all the bells and whistles under the same marketing name? How much different are the various product lines at the silicon level? It looks like the mega-FPGA market is alive and well, but I don't see how an FPGA company can ignore the low end of the market. There are just too many products using too much silicon for any silicon vendor to ignore. If Xilinx won't address the smaller devices I'm sure others will. -- RickArticle: 155544
I would add that most groups, this one included, have a large body of: "I'm= a GEN Y slacker. I need somebody to do my homework for me so that I can ge= t back to Facebook". This sort of content drives those of us that are FPGA= experts away. Forums need critical mass. This is the only FPGA-based dis= cussion that comes close. Good luck to FPGA Exchange.Article: 155545
GaborSzakacs wrote: > It seems that Xilinx is once again abandoning the low-cost > high-volume market in pursuit of those lucrative high-end > sockets. There latest announcement shows less roadmap > as the devices go towards the low end of the price curve: > > http://www.xilinx.com/products/technology/ultrascale/ Another indicator: They've dropped the Artix-7 SL/SLT lines that were announced in late 2012. Those were supposed to be available in small packages and with less LUTs, optionally without GTPs (AKA "bells and whistles"). Now they're back to the Artix-7 lineup that was originally announced from the beginning. When Lattice dropped the ECP4 before it even started, they told us they now plan to concentrate on low to medium density FPGAs, low power and smaller packages, since that is what X and A don't cover with their lineup and they don't stand a chance with the bigger parts. Seems to me that Xilinx is handing over that market share to them now. Greetings, SeanArticle: 155546
On Sunday, July 14, 2013 3:17:42 PM UTC-3, rickman wrote: > On 7/14/2013 2:04 PM, Leo wrote: >=20 > > Any good floorplanning literature (papers, books, etc.) ? I'm needing i= t for floorplanning FPGA architectures (Spartan 6), but any general text ab= out the subject would be cool. I already read fliptronics's introduction. >=20 >=20 >=20 > I don't know of any docs relevant to floorplanning other than what you=20 >=20 > might find at the Xilinx site. Floorplanning is not easy to use=20 >=20 > effectively in my experience. The one project where we really needed=20 >=20 > floorplanning I found it to be nearly impossible to use. That was in an= =20 >=20 > older Altera part using MaxPlusII. That tool was not so easy to=20 >=20 > manipulate as the Xilinx tools I expect. >=20 >=20 >=20 > Why do you need floorplanning? What do you expect to achieve using it? >=20 >=20 >=20 > --=20 >=20 >=20 >=20 > Rick I have a really tight design on resources (primarily carry logic and DSP, L= UT and Regs are around 63%). I was expecting to up a 50Mhz design into a 10= 0Mhz by overriding some of the placement done on map. The design is heavily= pipelined, but the external memory interfaces are among the critical paths= . The design needs to access one memory for reading and another one for wri= ting at the same time (on opposed banks), and then when an internal 'cycle'= finishes, switch the role of each memory. The main problem is that when I = floorplan it to achieve better timing (placing memory accessess in the mid-= point between opposed banks), the routing becomes heavily congested and doe= s not complete. I'm assuming that happens because there are signals running= vertically when memory accesses are being done horizontally. In the end I = think that I will have to reduce the resource utilization to achieve timing= , I mean remove a few parallel and independent pipes (with the performance = hit that it means).Article: 155547
On Monday, July 15, 2013 12:31:18 PM UTC-3, Gabor wrote: > Leo wrote: > > > Any good floorplanning literature (papers, books, etc.) ? I'm needing it for floorplanning FPGA architectures (Spartan 6), but any general text about the subject would be cool. I already read fliptronics's introduction. > > > > PlanAhead (now part of Xilinx tool chain) was developed by a company > > called Hier Design. It's likely that they had some significant white- > > papers on floorplanning. > > > > -- > > Gabor I can't find any, the only thing I found was the Acquisition of Hier Design by Xilinx.Article: 155548
On 7/17/2013 3:07 AM, Sean Durkin wrote: > GaborSzakacs wrote: >> It seems that Xilinx is once again abandoning the low-cost >> high-volume market in pursuit of those lucrative high-end >> sockets. There latest announcement shows less roadmap >> as the devices go towards the low end of the price curve: >> >> http://www.xilinx.com/products/technology/ultrascale/ > > Another indicator: They've dropped the Artix-7 SL/SLT lines that were > announced in late 2012. Those were supposed to be available in small > packages and with less LUTs, optionally without GTPs (AKA "bells and > whistles"). Now they're back to the Artix-7 lineup that was originally > announced from the beginning. > > When Lattice dropped the ECP4 before it even started, they told us they > now plan to concentrate on low to medium density FPGAs, low power and > smaller packages, since that is what X and A don't cover with their > lineup and they don't stand a chance with the bigger parts. Seems to me > that Xilinx is handing over that market share to them now. Certainly Lattice has an interesting line with the Silicon Blue products they bought last year. They are clearly targeting space constrained, portable apps with small, low cost devices in very tiny packages. It is hard to find a chip in the ice40 line that you can use without ultra fine pitch traces and vias. I haven't seen a similar product from anyone although I haven't looked hard at the low power Igloo parts. I don't see that they are truly low power once you start running them. -- RickArticle: 155549
On 7/17/2013 9:19 AM, Leo wrote: > On Sunday, July 14, 2013 3:17:42 PM UTC-3, rickman wrote: >> On 7/14/2013 2:04 PM, Leo wrote: >> >>> Any good floorplanning literature (papers, books, etc.) ? I'm needing it for floorplanning FPGA architectures (Spartan 6), but any general text about the subject would be cool. I already read fliptronics's introduction. >> >> I don't know of any docs relevant to floorplanning other than what you >> might find at the Xilinx site. Floorplanning is not easy to use >> effectively in my experience. The one project where we really needed >> floorplanning I found it to be nearly impossible to use. That was in an >> older Altera part using MaxPlusII. That tool was not so easy to >> manipulate as the Xilinx tools I expect. >> >> Why do you need floorplanning? What do you expect to achieve using it? >> >> -- >> >> Rick > > I have a really tight design on resources (primarily carry logic and DSP, LUT and Regs are around 63%). I was expecting to up a 50Mhz design into a 100Mhz by overriding some of the placement done on map. The design is heavily pipelined, but the external memory interfaces are among the critical paths. The design needs to access one memory for reading and another one for writing at the same time (on opposed banks), and then when an internal 'cycle' finishes, switch the role of each memory. The main problem is that when I floorplan it to achieve better timing (placing memory accessess in the mid-point between opposed banks), the routing becomes heavily congested and does not complete. I'm assuming that happens because there are signals running vertically when memory accesses are being done horizontally. In the end I think that I will have to reduce the resource utilization to achieve timing, I mean remove a few parallel and independent pipes (with the performance hit that it means). I'm not totally clear on all the details which can be important as there are more than one way to skin a cat. I think you are saying you have two memory interfaces which you are running in parallel. These memory interfaces are on the left and right sides of the chip so you have the control logic in the middle. Is there a reason why you can't put the memory interfaces on, say, the top and right to make them closer together and to potentially move the routing out of the way of the other logic? Or has your PCB been laid out? The problem you are seeing with floorplanning is exactly the sort of thing that can happen. While the tool may not understand your design, it understands the limitations of the chip. With the designer this is reversed. You are hitting a wall with the chip resources. So maybe don't floorplan for this problem. Can you add more pipeline stages? It is not unreasonable to add pipeline registers to break up the routing delays. No logic, just an extra FF in the paths that are giving the most trouble. Or maybe not floorplan the entire block of logic in one spot. Would it make sense to spread it out horizontally a bit which might leave some space for the vertical signals to weave through? But then 100 MHz is not all that fast. Have you looked at the details of the slow paths? Do you understand where the tool is having trouble meeting the timing goals? -- Rick
Site Home Archive Home FAQ Home How to search the Archive How to Navigate the Archive
Compare FPGA features and resources
Threads starting:
Authors:A B C D E F G H I J K L M N O P Q R S T U V W X Y Z