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Comment: Re: Price (Score 1) 337

by John Miles (#33148264) Attached to: Oscilloscopes For Modern Engineers?

Are you sure you're not talking about an 8000-series scope, rather than a 6000-series one? My MSO6054A was about $8500 on eBay, new in box but about half normal retail, and Agilent was running a special where they'd enable the maximum memory (8M points, which is actually just a software option) for free.

There's definitely no way to get 256M points on this particular scope, or to pay $100,000 for one.

But yeah, firmware support from Agilent has been outstanding. The DSO/MSO6000 line is rather 'mature' at this point, and they have released updates that enable a lot of features for free (8M, waveform statistics, RS-232 lister, and tracking cursors).

Comment: Re:An old Tektronix is fine for a modern engineer (Score 2, Informative) 337

by John Miles (#33134562) Attached to: Oscilloscopes For Modern Engineers?

I like the Tek 2430/2432/2440 scopes a lot, and used one for years in conjunction with a 2467, for those cases where analog-scope performance was needed. Apart from a few considerations like record length, this combination could easily stand up to any DSO costing less than several thousand dollars.

With the 2430-series scopes, the key points to watch out for are 1) make sure it passes its power-up self tests, as the CCD chips used for acquisition are no longer available; 2) avoid the original 2430s with no GPIB port if you think you will ever want to record screenshots from it; and 3) always use an external fan to cool the chips on the main board when servicing it. These scopes seriously stretched the performance envelope available at the time, and those custom chips can be replaced only by buying a parts mule.

Of course, if good ones are going for $200 with probes, it's probably a good idea to just go ahead and spend another $50-$100 on a parts unit to go with it...

Comment: Re:How about "Robots Only" (Score 5, Interesting) 224

by John Miles (#28796385) Attached to: White House Panel Seeks Input On Spaceflight Plans

Which is clearly not the case based on experiences with the mars rovers and similar devices.

Ridiculous. Think of one of the most interesting discoveries made by the Phoenix lander -- the frozen condensate that formed on one of the landing struts. A human would have noticed that immediately and been able to analyze it in detail. Conversely, a robotic probe can do only what it's programmed to do. All we can do is stroke our beards and say "Hmm, wonder what that is?"

When you're not only expecting the unexpected, but hoping for it, you want human boots on the ground. One human mission is easily worth twenty robotic missions.

Hell, NASA should consider offering one-way trips. They'd have enough volunteers to crash their Web server. Most people aren't doing anything that important or interesting with the rest of their lives, are they? Send one old guy with a shovel, a microscope, and a carbon-monoxide canister, and we'll learn more than we would from the next hundred years' worth of robots.

Comment: Re:I like the Digilent Nexys2 (Score 1) 185

by John Miles (#28737729) Attached to: Suggestions For Learning FPGA Development At Home?

Of course, the problem is that I don't know of anyone who can comfortably solder BGA chips.

People have been doing it with toaster ovens (http://www.instructables.com/id/Toaster-Oven-Reflow-Soldering-BGA/ and http://www.sparkfun.com/commerce/tutorial_info.php?tutorials_id=60&page=). I haven't tried that yet. I have soldered QFNs by laying down some solder paste and blasting the other side of the board with a heat gun, but it's a high-pucker-factor operation. I plan to try the toaster oven hack the next time I need to do that.

Comment: Re:I like the Digilent Nexys2 (Score 1) 185

by John Miles (#28727239) Attached to: Suggestions For Learning FPGA Development At Home?

True, but I was not able to get the FX2's pipe to operate reliably on every edge of IFCLK. This might have to do with the fact that my data transfer FPGA logic is clocked off IFCLK as well, but might be a limitation of the FX2 or board design.

Clocking the FPGA from the 48 MHz IFCLK is the right thing to do IMHO. That's how my setup's working. Email me offline if you want a code dump; no guarantees that it's optimal or even "correct", but I've run it for several days at a time without any problems.

You aren't trying to use asynchronous writes, are you? Those can't be pushed beyond about 6 MB/sec from what I could tell.

Also, what USB driver are you using? CyUSB? If so, make sure you use overlapped reads or you'll miss tons of data.

I agree that Gigabit (or 10G) is the way to go, but do you know of any convenient boards (like Nexys) for that ? Thank you !

Unfortunately, no... it seems there are numerous boards with 10/100 Ethernet interfaces but I haven't seen any GigE or better, except for the expensive Virtex-based ones like the NetFPGA board. Digilent had something called the FX12 for awhile that had a Webpack-supported Virtex chip and a GigE port, but it's been discontinued.

Comment: Re:Proof Graphics != Good Game (Score 5, Informative) 130

by John Miles (#28726781) Attached to: A History of Early Text Adventure Games

I really want to see some level of text based gaming come back.

Text gaming didn't leave, it just went indie. Some of the best works since the Infocom days have appeared in the annual rec.arts.int-fiction competition, the 15th of which is in progress now.

Someone below mentioned Photopia, and that's a good place to start (it took first place in the IF competition nine or ten years ago).

Comment: Re:I like the Digilent Nexys2 (Score 1) 185

by John Miles (#28699783) Attached to: Suggestions For Learning FPGA Development At Home?

I don't think the 8-bit path between the CY68013 and FPGA is a bottleneck, really. With an IFCLK of 48 MHz, you'd have to be able to shove 48 MBytes/sec through the endpoint to be bus-width limited, and that just isn't going to happen over USB 2.0. You'll have to spin on FIFO-full either way.

In practice about 32 MBytes/sec is about the best you can count on achieving, although I understand that the GNU Radio guys are pushing 40 MB/sec with some 8051 bus-mastering hacks.

Seems that most of the speed-constrained designs are moving to Gigabit Ethernet these days, avoiding the problem entirely.

Comment: Re:Try these modules (Score 1) 185

by John Miles (#28699695) Attached to: Suggestions For Learning FPGA Development At Home?

Opal Kelly modules are clean, well-documented designs, but because of their relatively high cost they're better thought of as embeddable modules rather than as learning platforms. For education and basic home tinkering, you want a cheap well-documented board with lots of peripherals to play with.

I think the best overall learning platform right now is the Nexys2. You can teach yourself everything from USB interfacing to VHDL/Verilog design for $129, and it's got a lot of switches, lights, ports, and outboard RAM to play with.

There are also a couple of reasonably priced books written especially for novices learning logic design with the Digilent platforms. $200 will get you both the basic- and advanced-level books from LBE and a Nexys2 to do the exercises. Very hard to beat that combination IMHO. (You can use the Nexys2 with the first book, even though it was written for the lower-end Basys board.)

Comment: Re:Don't buy a board and CtoVerilog.com (Score 4, Informative) 185

by John Miles (#28699569) Attached to: Suggestions For Learning FPGA Development At Home?

For a newbie, CtoVerilog.com is the mother of all bad ideas. Verilog is not isomorphic to C. Being able to represent a few trivial C loops as Verilog code will not help you learn what's going on under the hood, and it will not help you get the fundamental aspects of your design up and running.

Also, much of what's done in HDL is gluing other chips together. If you try to use CtoVerilog to make a high-speed USB chip talk to an ADC, the results will be amusing at best. If you find yourself wanting to use C in an HDL design, consider either falling back to a conventional microcontroller or using a software core to run it.

Censorship

FOIA Request For Pending Copyright Treaty Denied 364

Posted by kdawson
from the let-the-sunshine-in dept.
Penguinisto writes "According to CNET, Knowledge Ecology International's FOIA request for information about ACTA was denied. ACTA is the pending copyright treaty believed to have been authored by lobbyists for the content cartels. Even stranger, the denial cited 'national security reasons (PDF). While it is not unusual for the White House of any administration to block FOIA requests for national security reasons, one would think that a treaty affecting civil interests alone wouldn't qualify for such secrecy. Not exactly sure what involvement the former RIAA mouthpiece Donald Verelli (a recent Obama pick for the DOJ) may have in this." KEI is not alone; the European Parliament wants to see the ACTA documents too.
Windows

Windows 7 Lets You Uninstall IE8 474

Posted by samzenpus
from the if-thy-browser-offend-thee-pluck-it-out dept.
CWmike writes "A just-leaked build of Windows 7 lets users remove Internet Explorer, the first time that Microsoft has offered the option since it integrated the browser with Windows in 1997, two bloggers reported today. The move might have been prompted by recent charges by the European Union that Microsoft has stifled browser competition by bundling IE with its operating system, the bloggers speculated. One solution under consideration by the EU would require Microsoft to disable IE if the user decided to install a different browser, such as Mozilla's Firefox or Google's Chrome. Microsoft had no comment when asked to confirm whether Windows 7 will let users dump IE8 or whether the option was in reaction to the EU charges."
Microsoft

+ - Microsoft pulls plug on Xbox support->

Submitted by mytrip
mytrip (940886) writes "In early 2006, several months after it launched the Xbox 360, Microsoft ceased manufacturing the original Xbox. Today, the company pulled the plug on its first console entirely. The company has officially ended out-of-warranty support for the original Xbox, some eight and a half years after Bill Gates handed out the first device.

"On March 2, 2009, service repairs for Original Xbox video game systems for which the Warranty has expired will no longer be available," reads Microsoft's official support site. "Any other technical support, documents, and content, however, will continue to be available to all our customers. Although Microsoft is ending repair services for the Original Xbox, an upgrade program and support will be maintained for Original Xbox consoles that are still under Warranty.""

Link to Original Source
Censorship

More Websites Offending Thai Monarchy Blocked 220

Posted by timothy
from the really-could-skip-the-whole-prison-thing-altogether dept.
An anonymous reader writes "Thailand is ramping up their media wide censorship of anything that remotely offends Thai royalty. In the last three weeks, another 2,300 websites have been blocked. Another ~4,000 are soon expected. And not just websites, but books as well as the Economist have been blocked. And anyone caught publishing such material, including foreigners, will get 3 to 15 years in a Thai prison. You don't want to be in a Thai prison!"
Windows

Windows 7 To Come In Multiple Versions 821

Posted by kdawson
from the win-7-ready dept.
Crazy Taco writes "Tom's Hardware reports on newly discovered screenshots that reveal Microsoft is planning to release their newest version of Windows in multiple confusing versions ... again. The information comes from the latest version of the Windows 7 beta, build 7025 (the public beta is build 7000), and shows a screen during installation that asks the user which version of the OS he or she would like to install. Who's up for guessing what the difference is between Windows 7 'Starter' and Windows 7 'Home Basic?'"

For God's sake, stop researching for a while and begin to think!

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