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Comment: Re: RS-232 WattsUp, Humidity Sensor, RPi 1, WiFi, (Score 1) 215

by jddj (#49827767) Attached to: Ask Slashdot: Your Most Unusual Hardware Hack?

Good point. Making the RPi talk RS232 to the ancient WattsUp took only a level shift and decidedly retro baud rate (the summary said "outdated"). (FYI, there's now a "net connected" WattsUp, but they want you to go through their proprietary portal: NFW! Hunk of junk!)

I probably should've mentioned that I initially used Google Analytics to build the graphs. It's really not designed for that.

The duct tape-like approach I took with hardware I had sitting around to bend it to my will (vs. buying something off the shelf - not to mention final fit and finish) make it feel like a hack to me.

But OK, point made. I DQ myself.

Comment: RS-232 WattsUp, Humidity Sensor, RPi 1, WiFi, GPIO (Score 3, Interesting) 215

by jddj (#49824533) Attached to: Ask Slashdot: Your Most Unusual Hardware Hack?

Put it all together for near-real-time track of how much it costs to keep my basement at a given humidity.

The Raspberry Pi caches readings in a local database in case it can't connect to the web, then stores in a database on my web server. The database ingestion also keeps a 2-hour running average to smooth things out a bit.

When I set it up, I thought it wasn't working right - I saw sawtooth-like patterns in the humidity data. Turned out, it was working perfectly: the resolution of the humidity sensor was good enough that I could watch the humidity in the room rise until the dehumidifier kicked on!

Comment: Re:why not a web page? (Score 3, Interesting) 161

by jddj (#49563175) Attached to: Has the Native Vs. HTML5 Mobile Debate Changed?

It's important to understand that the context of use for a mobile web page is different from that of a successful mobile app.

There are a bunch of dumb apps developed for online news sites - as though I'd ever want to go to just one news site, vs. have the mobile web spread out before me.

OTOH, good mobile apps do things that the mobile web doesn't or can't. Perform read/write operations on local data. Use local processing power - as much as is available. Access local sensors not available to mobile web. Aggregate data from multiple sources - perhaps blending web and local data.

Even apps that do nothing more than provide deep search - if the vertical market for the app is well defined (Movie geeks: IMDB, small investors: finance apps...), it's possible for a mobile app to excel over a web site by providing native gadgets and a platform native UI that doesn't have to leave room for the (admittedly minimal) mobile browser UI.

Finally, mobile apps can scrape a bunch more information from the user's device than can mobile web. Definitely a help in monetizing a popular vertical, if you roll that way.

Comment: Re:Least common denominator (Score 1) 161

by jddj (#49562973) Attached to: Has the Native Vs. HTML5 Mobile Debate Changed?

Disagree with your comments on CG UI.

I used Lightwave 3D for quite a while. It's built with one of these cross-platform Frankenstein UIs, and frankly, that part sucks.

I want an app to behave on a Mac like a Mac app, on a Windows PC like a Windows app, and on a Linux box with whatever feeble attempt at consistency it can muster.

Ditto goes for iOS and Android. Can't stand seeing the iOS "BACK" button on an Android screen. Dumb, dumb, dumb.

Comment: QNAP TS-something-something with Linux (Score 4, Interesting) 253

by jddj (#49289019) Attached to: Ask Slashdot: Building a Home Media Center/Small Server In a Crawlspace?

I'm using a TS-119+ with a 2TB disk inside. It's sitting in my wiring closet.

It's running MythTV for my TV/UPnP server, MythWeb for programming, Mediatomb to serve photos/videos via UPnP, and mt-daapd as an iTunes Music Server. I use PS/3s for the TV front-ends, and Roku Soundbridge 500s, 1000s, and 2000s for the music players.

It's about as close to silent as you get - I think it's fanless (you can see I'm not concerned enough about noise to find out). And it uses about 6w when it's idling.

I got into NAS solutions after I figured out running my MythTV system 24x7 was like leaving a 100 watt lightbulb on all the time, even when I didn't need it. I measured my old beige-box PC with a watt meter: a continuous 95 watts. And loud fans.

The QNAP delights me. All I could ask for that it doesn't do well is transcoding. There's just not enough CPU for it. But that'll come in time with some other NAS unit, or with offloading it via scripting to a full PC or Mac, when I get around to it.

Comment: They ALREADY figured out why - it's in TFA (Score 2) 253

by jddj (#49161639) Attached to: 20-Year-Old Military Weather Satellite Explodes In Orbit

From TFA:

"The 'catastrophic event' produced 43 pieces of space debris, according to Air Force Space Command, which disclosed the loss of the satellite Feb. 27 in response to questions from SpaceNews."

Just what kind of questions was SpaceNews asking, that the satellite would explode in response? They should STFU pretty quick, before we lose everything in LEO!

In space, no one can hear you fart.