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Comment Re:Where Are Today's Hobbyists? (Score 1) 612

I accidentally posted anonymously, so here's what I wrote, and what I want to add to:

Well, if you want to tinker with 1970s-era home computer technology, the parts for doing so still exist. One of my builds had a Zilog Z80 processor, 32kB of SRAM and EEPROM memory (no interface circuitry required), plus a 4 MHz clock generator. For output, I had 2 latch DACs and a latch gate, hooked up to the X, Y and Z (intensity) inputs of an oscilloscope. Plotting vectors on the screen every 20 or 40 ms only takes up a few processor cycles. Input from a PS/2 keyboard runs at such a low baud rate that you don't really need to worry about having a chip for it either. Use a simple multiplexer and a couple of logical gate chips to set up interrupt triggers for the screen refresh and keyboard input. I believe the PS/2 has a clock pin, so just trigger when that's high or low. You could hook up your EEPROM so the processor can flash it, for some primitive storage, or you could hook up an old tape deck to some simple analog circuitry, for Commodore 64-style storage. IBM PC floppy drives also use a very simple interface, but you'd need more logical circuitry. You could toss on another Z80 as an I/O co-processor and run them in lockstep with the 4 MHz clock. The possibilities for fun tinkering are endless.

I must admit that I've had trouble finding an easy, inexpensive way of prototyping. Sending PCB layouts to fabs is a little bit expensive, especially if you make a mistake. I've used veroboard in the past, but all the soldering for bus lines can take its toll on the copper tracks, especially if you make mistakes, and you often end up having to throw out a board after a while. I've been tempted to try wirewrapping tools lately, because of how easy it is to fix a mispatched connection. I have also experimented with laser printer etching, but it's time consuming, and the chemical brew you need for it is rather nasty. The closest thing I have gotten to "real time development" in the way you would do with software is SPICE, specifically LTspice in my case, but you have to watch out for some things. In the simulation, conductors are ideal and have no time delay, resistance or capacitance, and components behave perfectly, with no thermal noise, so you risk doing an entire design in SPICE, and then discovering later that you actually needed those seemingly optional decoupling capacitors for the circuit to remain stable. This becomes especially apparent as you get closer to the gigahertz range (and is part of the reason why circuits have kept shrinking over the years, as this reduces those side effects).


Submission + - Curiosity Rover Finds "Ancient Streambed" Proving Mars Once Had Water ( 3

eldavojohn writes: As NPR reports, NASA's Curiosity Rover has tweeted pictures of proof of water on Mars. Indications arose earlier this year but researchers are now calling this proof of a stream ankle to hip deep running at about three feet per second judging by the pictures. The shapes prove these rocks were weathered as they were transported by something and the sizes tell you that that something couldn't be wind.

Submission + - Sharp develops see-through solar panel for windows (

An anonymous reader writes: Solar power may hold the promise of free energy from the sun, but the panels used are expensive and do take up a lot of room. Typically you’ll find them installed on a roof or filling an area of land next to the building requiring the green energy. But now Sharp is offering up a third option: solar panels that double as windows.

Sharp has managed to develop a solar panel that takes the form of a sheet of glass and only partially blocks light passing through it. That allows it to still generate energy, but also act as a window. Sharp achieved this by cutting tiny slits in thin-film silicon PV cells. The trade-off for cutting into the cells is lower energy generation. Sharp can currently produce the see-through panels at sizes up to 1.4 x 1.0 meters, and a thickness of just 9.5mm. Each panel weighs 33kg and can produce a maximum output of 95W. Pricing has not yet been revealed.

Comment Re:Sarcastic or not? (Score 1) 353

The funny bit is that a pair of near field monitors can be had for 400 dollars or less these days and with built-in matched amplifiers for each element in the speaker cabinet, their accuracy often beats more expensive Hifi systems.


Submission + - Have you ever had the Programmer's Blues? (

ThJ writes: "This is a little tale of the troubles I have had since I started working as a programmer, and it might come off as a rant. I am currently 26 years old and I have been into electronics and computers since I was very young. With this article, I hope to share my experiences with other programmers, and get some useful feedback from the web community."

Ubuntu Linux vs. Mac OS X 479

An anonymous reader writes "An article on InformationWeek pits an Apple user against an Ubuntu Linux user (although he talks about other distros as well) as to which OS makes a better desktop operating system. As might be expected, the conclusion seems to be "different strokes for different folks," but it's interesting to see Microsoft cut (mostly) out of the equation."
Operating Systems

Submission + - Linux Gains Two New Virtualization Solutions

An anonymous reader writes: The upcoming 2.6.23 kernel has gained two new virtualization solutions. According to KernelTrap, both Xen and lguest have been merged into the mainline kernel. These two virtualization solutions join the already merged KVM, offering Linux multiple ways to run multiple virtual machines each running their own OS.
Linux Business

Submission + - On the rPath to virtual containerization (

willdavid writes: "According to Jeff Gould, it's becoming increasingly clear that the most important use of virtualization is not to consolidate hardware boxes but to protect applications from the vagaries of the operating environments they run on. It's all about "containerization." He talks about how Linux applications could be distributed much easier using a fully integrated OS-middleware-application stack. rtual-containerization.html"
It's funny.  Laugh.

Submission + - Linux lotto tickets?

An anonymous reader writes: I'm not quite sure where this Linux lotto ticket originates from... but can you identify the possible copyright violation? Release the hounds!
Linux Business

Submission + - No Wine for Dell's Prebundled Linux Machines

UCSF Geek writes: Mark Shuttleworth, the founder of Ubuntu Linux, does not want to position Ubuntu and Linux as a cheap alternative to Windows. As such, Dell will not include open-source software such as Wine, which lets users run Windows programs on Linux, with the PCs it plans to bundle with Ubuntu, he tells eWeek here(,1895,2125848, 00.asp). He goes on to say that "while Linux is an alternative to Windows, it is not cheap Windows. Linux has its own strengths, and users should want it because of those strengths and not because it's a cheap copy of Windows."

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PL/I -- "the fatal disease" -- belongs more to the problem set than to the solution set. -- Edsger W. Dijkstra, SIGPLAN Notices, Volume 17, Number 5