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Submission + - Remote-booting USB-powered devices? 2

phlawed writes: USB ports are everywhere. It is very convenient for powering low-power devices, and by using a run-of-the-mill phone charger you can easily get 10+ watts or so. In other words: everyone already has the generic power supply and power cable. No issue with voltage or polarity. Perfect for the hobbyist market.

Another ubiquitous power source (in the enterprise environment) is Power over Ethernet. Active PoE splitters for 12V output are available for ~6-7 USD and up on eBay. With PoE you get networking and power over the same wires, and booting your (possibly borked) PoE device is a matter of instructing the PoE source to cycle the power on that port. (Also, USB chargers with 12V input are available for less than 1 USD on eBay. They are likely all crap, though.)

I am looking for the combination of these two concepts in a compact, affordable, quality product. I found one product offering USB power from PoE. That product appears to have left out Ethernet and has a MSRP of 30 USD. Otherwise, I find PoE wall sockets for a MSRP of USD 100 or more. It appears excessive, given the cost figures of the pieces listed above.

So, if it does not already exist... anyone feel like running with this on your favorite crowdsourcing platform? Any experienced electronics people who can do a back-of-the-envelope calculation for cost of parts and assembly?

Comment Re:Apple ][+ (Score 1) 81

I bought a fully working //c last year for £120. Unboxed though. (And a working Apple II euro the year before for about the same) If you look about, then most of these old ones don't go for much at all really. The esoteric ones sometimes do. e.g. check old ebay listings for the MK14 and Jupiter Ace ... Apple /// and Lisa... Now they'll be worth something... -Gordon

Comment There are only 3 COBOL programs... (Score 3, Interesting) 318

The "Input and Validate"
The "Update"
and the "Print"

At least that's what a lecturer told me many years ago when I did COBOL at uny. I didn't get on with it initially, then I got bored and opened the book... Then I learned that what the lecturer was telling me was his idea of what COBOL ought to look like and not generic. It got a little more interesting after that (along with the student competition to see how many errors we could make the compiler generate with the minimal amount of syntax errors - one mis-placed full-stop managed to get it to the limit of 999 once)

I've not written a COBOL program for over 30 years now. I don't miss it.


Comment Re:Quality article, full of technical details (Score 1) 83

The price is affordable for "carriers" (ie. telcos and thererfore peanuts for mlitary), and you can buy true 1GHz full duplex units off the shelf today.

There is a problem with 60GHz though - range. It's the O2 absorption frequency, so max is 1-2Km...

However there are other frequencies in that area of the spectrum which I know are being investigated/used...

Comment Re:Put stuff in sealed plastic cases? (Score 2) 434

I recently bought an old Apple II.. And tried out some of the 30+ year old 5.25" floppies I had in storage all these years (I've got 100's). Most of them still work!

I'm suspecting that the bit-density is so low that it's hard for them not to work, but I was still plesantly surprised.

Now all I need is an Apple II serial card so I can get some of the source code for stuff I write way back then off the floppies onto something else...

Comment Still at the prototype Stage? (Score 4, Informative) 74

They're a bit late then. There are already several kits out there - both breadboard and protoboard with solder holes in them. Get with the times!

Try this:

Or this:

etc. I currently have the SKPang one for my Pi.

Open Source

Linux 3.2 Has Been Released 271

diegocg writes "Linux 3.2 has been released. New features include support for Ext4 block size bigger than 4KB and up to 1MB, btrfs has added faster scrubbing, automatic backup of critical metadata and tools for manual inspection; the process scheduler has added support to set upper limits of CPU time; the desktop responsiveness in presence of heavy writes has been improved, TCP has been updated to include an algorithm which speeds up the recovery of connection after lost packets; the profiling tool 'perf top' has added support for live inspection of tasks and libraries. The Device Mapper has added support for 'thin provisioning' of storage, and a support for a new architecture has been added: Hexagon DSP processor from Qualcomm. New drivers and small improvements and fixes are also available in this release. Here's the full list of changes."

Comment Re:Oblig.... (Score 1) 271

Heh... ZZ needs 2 keypresses, :x three (because it's :x RETURN) Similarly :wq is 4 keypresses.

Of-course someone might argue that needing the shift key is really another keypress, but they're probably emacs users... ;-)

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I bet the human brain is a kludge. -- Marvin Minsky