A Three Hour Tour

Maybe it’s just me, but I often wish I knew the temperature outside, and maybe the temperature inside too.  Not because it is really significant or anything, but just out of curiosity.  Then I thought, why not log the temperature so I can graph it over a long period of time and see weather trends?

So I think for a moment, and think… how can I read the temperature?  Immediately I think of the Lego Mindstorms RCX and its temperature sensor.  So I rig up a program for the RCX that logs temperature values and a Linux program that periodically uploads the datalog, and I have success!

But not quite.

First, the RCX is rather finicky, not to mention expensive. I need to have it plugged in via a wall plug, which means I need to take out the batteries, which means that if the cord is jostled or the power fails, I need to re-download the firmware and the program.  It also communicates via IR, so if the sun hits it in the right direction or it loses line-of-sight with the transmitter, the data is lost.  Annoying.  So I set out to do one better.

My current set-up is available from my room in Saxon, dutifully logging away every fifteen seconds for as long as the computer is running.

So I’m blogging on a time crunch (never a good idea!) so here’s a teaser for next time:  I’m using the One-Wire Bus to communicate with a transistor-shaped device over phone wires.  A USB->Serial port interface, on a breadboard, provides the PC to one-wire bridge, and a custom program grabs the data and logs it.  More to come!

Isn’t it odd how our brains notice things? For example, I seem to have a habit of looking at the clock at exactly 11:34, which when turned upside-down spells out “hell”. Now do I really have that habit, or do I just happen to notice those times because 11:34 has a (somewhat immature and meaningless) significance?

Recently the MacBook Air computer has caused some issues on airport security: http://www.michaelnygard.com/blog/2008/03/steve_jobs_made_me_miss_my_fli.html

To make a long story short, some ppor traveller missed his flight because the TSA didn’t know that the MacBook Air was a real laptop.

Recently the TSA gave their explanation for the whole issue in a blog post: http://www.tsa.gov/blog/2008/03/apple-macbook-airs-are-cleared-for.html

Basically what happened was that this traveller was simply trying to bring his laptop through security. Quite simple… not a problem. Certainly not intended as an attempt to bring down a plane.

To the TSA agent, however, this was a unknown traveller bringing some odd-looking electronic device through a checkpoint. And if it’s your job to make sure that no dangerous devices make it on the airplane, you sure aren’t going to let an odd-looking device through without further investigation.

Unfortunately for our poor traveller, being pulled aside for a secondary screening, and missing his flight, sure seems like overkill for what was an innocent piece of luggage. But the TSA agent didn’t know that, and if the “device” did end up causing a tragedy, even if he wouldn’t be legally responsible, he’d certainly feel terrible.

So next time you fly, and get hassled by the TSA, remember that they are just trying to keep people safe. And keeping people safe requires that if there’s even a shadow of a doubt that something might be dangerous, it must be treated as a real danger.

Something to think about next time you go to an airport.

Well if you read in Building my first PC, you’d know I was having video card issues – the GeForce 7200 card was running too hot.  My case doesn’t get much ventilation down there.

So I bought a Zalman VGA cooling fan, thinking I’d hook it up to the card.  A large fan would provide better cooling and be quieter than the tiny excuse for a fan that comes with the card.

It didn’t fit! Despite claiming compatability with the GeForce 7xxx series cards, it didn’t fit the 7200!  So I did the most logical thing and returned the video card.  The video card? Now that I had a fan, I wasn’t worried about those tiny noisemakers from before.  I now have a GeForce 8500 card, with DirectX 10 support, and a nice quiet fan.  My graphics performance subscore jumped to 4.8!

All in all, I’d say I have pretty good performance for the price.  I still need to run some tests on it (Prime95) and perhaps try overclocking it a bit, provided it doesn’t become too hot or less stable.

I’ve recently embarked on a mission to build my own PC, which is disappointingly less technical than it would seem.  I opted for a middle-of-the-road PC, trying to get the most for my money (ie. no $500 graphics cards, sorry).

I am now typing this on the new PC, it’s up and running.  Some specs:

• Intel Core 2 Duo E6400: 2.13 GHz, 64-bit, virtualization support (the OS developer in me is drooling about now)
• Gigabyte GA-965P-S3, 6 SATA, plenty of USB, 3 PCI, 3 PCI-X x1, 1 PCI-X x16, serial port (for OS debugging), high-def audio, up to 8GB RAM.
• 2GB of RAM
• 300GB 7200RPM SATA hard disk
• Antec Solo case, Antec Earthwatts 80+ 380W PSU
• eVGA GeForce 7200 fanless video card
• SATA CD/DVD-RW drive
• 3.5″ internal USB memory card reader

I’ve installed Windows Vista Ultimate 64-bit on this, and so far it’s running perfectly.  The provided Intel processor cooler seems to have trouble starting up – the fan takes a while to get going.  I have a feeling the motherboard isn’t providing enough voltage until the chip heats up a bit.  But the thing idles around 30C, pretty good.  The video card is another issue entirely.

The first video card I got was the eVGA GeForce 7600, which was only $20 more at my local Frys.  I stuck it in the motherboard and booted up, and was dismayed to find a snake in my computer.  The video card hissed like a snake.  Try clenching your teeth, opening your lips, and blowing.  For me at least, that’s what the fan sounded like.  It seems to be because the fan is blowing air through the narrow slats of a heatsink.

Without the fan noise, the computer would be almost silent.  Given I didn’t need a super-high-power card anyways, I returned it for the 7200.  A fanless card obviously will be silent.  And I was pleasantly surprised by its performance, although it tends to run rather hot.  But that’s to be expected of something passively cooled.

Vista’s performace statistics are:

• Processor: 5.0
• Memory: 5.5
• Graphics: 3.6
• Gaming Graphics: 3.0
• Hard Disk: 5.7

Because I do also run Linux (now Ubuntu Feisty – sorry Dan!) I made sure to install Ubuntu on it and give that a try.  Didn’t have a chance to see if XGL would work, although with an nVidia card I’ve got a chance.  Maybe I’ll set up a dual-boot configuration sometime.

My only regret is that the case is shiny – I was expecting a matte black finish.  Oh well, it’s good enough and not worth the hassle of sending it back to Newegg.

As for dual-booting, I’ve got a few tricks about that (including how to keep Windows happy) that I don’t see anywhere else on the internet.  Expect a post coming up about that.