This is a multi-part message in MIME format. --------------080704020804030404080408 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit The same holds true for CoolRunner XPLA3 devices (pin compatible with Altera devices (and they can be powered from fruit). Ulf Samuelsson wrote:>"Jeff Peterson" <jbp@cmu.edu> wrote in message >news:369b6e8b.0311190715.4d66f38f@posting.google.com... > > >>We are building a new radio telescope called PAST >>(http://astrophysics.phys.cmu.edu/~jbp/past6.pdf) >>which we will install at the South Pole or in Western China. >> >>To make this work, will need to sample (6 to 8 bit precision) dozens >>of analog voltages at 400 Msample/sec and feed these data streams into >>PCs. One PC per sampler. >> >>The flash ADCs we need are available (Maxim), but we are finding it >>difficult to get the data into the PC. >> >>One simple way would be to use SCSI ultra640, but so far I have not >>found any 640 adapters on the market. Is any 640 adapter available? >>anything coming soon? >> >>or we could go right into a PCI-X bus. has anyone out there >>done this at 400 Mb/s? is this hard to do? FPGA core liscense >>for this seems expensive ($9K), with no guarentee of 400 mByte rates. >> >>is there a better way? >> >>thanks >> >>-Jeff Peterson >> >> > > >Why dont you get an AGP Graphics processor, and try to connect your ADCs to >the GPU Memory Bus. >Run a PCI card for graphics on the PC. > >The GPUs are programmable , so you might even be able to do some processing >inside... > >Since you only need 400 MSamples/S, you could live with the Maxims. > >If you want to get some real speed, then maybe something like the Atmel >TS8308500 (500 Mspl/s), TS8388B (1 Gspl/s) or TS83102G0B (Gspl/s) could be >of interest. >Going up to Giga Samples per second, would make your problem worse though >:-) > >http://www.atmel.com/dyn/products/datasheets.asp?family_id=611 > > >--------------080704020804030404080408 Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: 7bit <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta http-equiv="Content-Type" content="text/html;charset=ISO-8859-1"> <title></title> </head> <body text="#000000" bgcolor="#ffffff"> <font face="Arial">The same holds true for CoolRunner XPLA3 devices (pin compatible with Altera devices (and they can be powered from fruit).<br> <br> </font><br> Ulf Samuelsson wrote:<br> <blockquote type="cite" cite="midbpis10$q70$1@public2.atmel-nantes.fr"> <pre wrap="">"Jeff Peterson" <a class="moz-txt-link-rfc2396E" href="mailto:jbp@cmu.edu"><jbp@cmu.edu></a> wrote in message <a class="moz-txt-link-freetext" href="news:369b6e8b.0311190715.4d66f38f@posting.google.com">news:369b6e8b.0311190715.4d66f38f@posting.google.com</a>... </pre> <blockquote type="cite"> <pre wrap="">We are building a new radio telescope called PAST (<a class="moz-txt-link-freetext" href="http://astrophysics.phys.cmu.edu/~jbp/past6.pdf">http://astrophysics.phys.cmu.edu/~jbp/past6.pdf</a>) which we will install at the South Pole or in Western China. To make this work, will need to sample (6 to 8 bit precision) dozens of analog voltages at 400 Msample/sec and feed these data streams into PCs. One PC per sampler. The flash ADCs we need are available (Maxim), but we are finding it difficult to get the data into the PC. One simple way would be to use SCSI ultra640, but so far I have not found any 640 adapters on the market. Is any 640 adapter available? anything coming soon? or we could go right into a PCI-X bus. has anyone out there done this at 400 Mb/s? is this hard to do? FPGA core liscense for this seems expensive ($9K), with no guarentee of 400 mByte rates. is there a better way? thanks -Jeff Peterson </pre> </blockquote> <pre wrap=""><!----> Why dont you get an AGP Graphics processor, and try to connect your ADCs to the GPU Memory Bus. Run a PCI card for graphics on the PC. The GPUs are programmable , so you might even be able to do some processing inside... Since you only need 400 MSamples/S, you could live with the Maxims. If you want to get some real speed, then maybe something like the Atmel TS8308500 (500 Mspl/s), TS8388B (1 Gspl/s) or TS83102G0B (Gspl/s) could be of interest. Going up to Giga Samples per second, would make your problem worse though :-) <a class="moz-txt-link-freetext" href="http://www.atmel.com/dyn/products/datasheets.asp?family_id=611">http://www.atmel.com/dyn/products/datasheets.asp?family_id=611</a> </pre> </blockquote> </body> </html> --------------080704020804030404080408--
400 Mb/s ADC
Started by ●November 19, 2003
Reply by ●November 20, 20032003-11-20
Reply by ●November 21, 20032003-11-21
> If you want to get some real speed, then maybe something like the Atmel > TS8308500 (500 Mspl/s), TS8388B (1 Gspl/s) or TS83102G0B (Gspl/s) could be > of interest. > Going up to Giga Samples per second, would make your problem worse though > :-) > > http://www.atmel.com/dyn/products/datasheets.asp?family_id=611I think we will try atmel...Jeff
Reply by ●November 21, 20032003-11-21
> The fastest slots on a PC Mainboard are the memory expansion slots. > It's an easy to design hardware interface and if you use a server > mainboard with multiple memory channels you get a hell lot of > bandwidth. I remember seeing a cryptoaccelerator on a DIMM somewhere > and SUN used to place graphics boards in memory slots.hmmm...interesting idea
Reply by ●November 21, 20032003-11-21
Ulf Samuelsson wrote:> > If you want to get some real speed, then maybe something like the Atmel > TS8308500 (500 Mspl/s), TS8388B (1 Gspl/s) or TS83102G0B (Gspl/s) could be > of interest. > Going up to Giga Samples per second, would make your problem worse though > :-) > > http://www.atmel.com/dyn/products/datasheets.asp?family_id=611 >When did Atmel start making flash ADCs? Can someone actually buy these now? How much do they cost? see: http://dustbunny.physics.indiana.edu/~paul/hallDrd for our "merely" 250 Msps particle physics project. Paul Smith Indiana University Physics
Reply by ●November 21, 20032003-11-21
"Paul Smith" <ptsmith@no_spam.indiana.edu> wrote in message news:bpleh0$fdm$1@hood.uits.indiana.edu...> Ulf Samuelsson wrote: > > > > > If you want to get some real speed, then maybe something like the Atmel > > TS8308500 (500 Mspl/s), TS8388B (1 Gspl/s) or TS83102G0B (2 Gspl/s)could be> > of interest. > > Going up to Giga Samples per second, would make your problem worsethough> > :-) > > > > http://www.atmel.com/dyn/products/datasheets.asp?family_id=611 > > > > When did Atmel start making flash ADCs? Can someone actually buy these > now? How much do they cost?Yep, have been around for quite some time.> see: > > http://dustbunny.physics.indiana.edu/~paul/hallDrd > > for our "merely" 250 Msps particle physics project.My guess is maybe $500 for the 1 G sample 8 bit devices. 2-3 x the price for the 2 G sample 10 bit device. This is for commercial spec, mil spec devices are more expensive. How many do you need? -- Best Regards Ulf at atmel dot com These comments are intended to be my own opinion and they may, or may not be shared by my employer, Atmel Sweden.> > Paul Smith > Indiana University Physics >
Reply by ●November 21, 20032003-11-21
Reply by ●November 22, 20032003-11-22
"Ulf Samuelsson" <ulf@NOSPAMatmel.com> wrote in message news:bpis10$q70$1@public2.atmel-nantes.fr...> > If you want to get some real speed, then maybe something like the Atmel > TS8308500 (500 Mspl/s), TS8388B (1 Gspl/s) or TS83102G0B (Gspl/s) could be > of interest. > Going up to Giga Samples per second, would make your problem worse though > :-)Maxim also has the MAX104 (1 Ghz,) and MAX108 (1.5Ghz) and other lower speeds in the range 500Mhz and up.
Reply by ●November 22, 20032003-11-22
In article <369b6e8b.0311191630.15ece843@posting.google.com>, Jeff Peterson wrote:> we will take about 64K samples, then can pause while processing... > however all the time we are pausing we are losing data. so we do want to > keep the duty cycle up. 50% duty cyle is not a problem. 5% would be.It sounds like you *really* want to do the FFTs on PCs, rather than on an outboard DSP. (for your application that might make sense, as you're only building one or a few of these things, and software development will be hugely easier) You might try "striping" the data across multiple PCs. After the ADC, block the data into 64K "packets", and have 2 or 3 links to FPGA "NICs" that receive blocks of 64k samples (plus maybe a sequence number) and DMA them over PCI. Even if you do try to convert to SCSI or Fibre Channel and use standard adapters, you might still want to consider the striping idea. -- ..................................................................... Peter Desnoyers (617) 661-1979 pjd@fred.cambridge.ma.us 162 Pleasant St. Cambridge, Mass. 02139
Reply by ●November 23, 20032003-11-23
On Sat, 22 Nov 2003 15:50:45 +0100, "Morten Leikvoll" <m-leik@online.nospam> wrote:> >"Ulf Samuelsson" <ulf@NOSPAMatmel.com> wrote in message >news:bpis10$q70$1@public2.atmel-nantes.fr... >> >> If you want to get some real speed, then maybe something like the Atmel >> TS8308500 (500 Mspl/s), TS8388B (1 Gspl/s) or TS83102G0B (Gspl/s) could be >> of interest. >> Going up to Giga Samples per second, would make your problem worse though >> :-) > >Maxim also has the MAX104 (1 Ghz,) and MAX108 (1.5Ghz) and other lower >speeds in the range 500Mhz and up. > >I worked on something similar that never got built. We wanted to record the output of multiple 200MHz 12 Bit ADC and store it in a harddrive. There was some company that sold an optical interface harddrive that could manage the speed but we had decided to use multiple harddrive and split the data among the drives to achieve the desired throughput similar to what RAID drives do. As for FFT's they are done way faster in a FPGA than in any processor including DSP processors. The only problem is the cost of the FPGA if you need really big FFT's (4K 24 bit wide). The card I was working on was basically an RF spectrum analyzer for a missile so things needed to be done in a hurry. The harddrive thing was for a prototype so we wanted to store the RF we were seeing without processing it. Ray
Reply by ●November 24, 20032003-11-24
Jeff Peterson wrote:>>The fastest slots on a PC Mainboard are the memory expansion slots. >>It's an easy to design hardware interface and if you use a server >>mainboard with multiple memory channels you get a hell lot of >>bandwidth. I remember seeing a cryptoaccelerator on a DIMM somewhere >>and SUN used to place graphics boards in memory slots. > > hmmm...interesting ideahere's a reasonable place to start digging: http://citeseer.nj.nec.com/leong01pilchard.html John
