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Space

How They Built the Software of Apollo 11 220

Posted by kdawson
from the we-had-to-use-the-letter-o dept.
LinuxScribe tips a piece up at Linux.com with inside details on the design and construction of the Apollo 11 code. There are some analogies to open source development but they are slim. MIT drafted the code — to run on the Apollo Guidance Computer, a device with less grunt than an IBM XT — it had 2K of memory and a 1-MHz clock speed. It was an amazing machine for its time. NASA engineers tested, polished, simulated, and refined the code. "The software was programmed on IBM punch cards. They had 80-columns and were 'assembled' to instruction binary on mainframes... and it took hours. ... During the mission, most of the software code couldn't be changed because it was hard-coded into the hardware, like ROM today... But during pre-launch design simulations, problems that came up in the code could sometimes be finessed by... computer engineers using a small amount of erasable memory that was available for the programs. The software used a low-level assembly language and was controlled using pairs or segments of numbers entered into a square-shaped, numeric-only keyboard called a Display and Keyboard Unit... The two-digit codes stood for 'nouns' or 'verbs,' and were used to enter commands or data, such as spacecraft docking angles or time spans for operations." Reader Smark adds, "The Google Code Blog announced today that the Virtual AGC and AGS project has transcribed the Command Module and Lunar Excursion Module code used during the Apollo 11 moon landing. The code is viewable at the VirtualAGC Google Code Page."
Windows

Windows 95 Almost Autodetected Floppy Disks 334

Posted by timothy
from the be-nearly-nostalgic dept.
bonch writes "Windows 95 almost shipped with a technique for detecting whether a floppy disk was inserted without spinning up the drive. Microsoft's floppy driver developer discovered a sequence of commands that detected a disk without spinup — unfortunately, unspecified behavior in the floppy hardware specification meant that half the drives worked one way and half the other, each giving opposite results for the detection routine. Microsoft considered a dialog prompting the user to insert a disk to 'train' the routine, but the idea was scrapped."
Biotech

+ - Liquid crystal phases of DNA, beginning of life?->

Submitted by
An anonymous reader writes "A team led by the University of Colorado at Boulder and the University of Milan has discovered some unexpected forms of liquid crystals of ultrashort DNA molecules immersed in water, providing a new scenario for a key step in the emergence of life on Earth.

CU-Boulder physics Professor Noel Clark said the team found that surprisingly short segments of DNA, life's molecular carrier of genetic information, could assemble into several distinct liquid crystal phases that "self-orient" parallel to one another and stack into columns when placed in a water solution. Life is widely believed to have emerged as segments of DNA- or RNA-like molecules in a prebiotic "soup" solution of ancient organic molecules.

A paper on the subject was published in the Nov. 23 issue of Science. The paper was authored by Clark, Michi Nakata and Christopher Jones from CU-Boulder, Giuliano Zanchetta and Tommaso Bellini of the University of Milan, Brandon Chapman and Ronald Pindak of Brookhaven National Laboratory and Julie Cross of Argonne National Laboratory. Nakata died in September 2006."

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Moon

+ - Vote to Eliminate Leap Seconds 6

Submitted by Mortimer.CA
Mortimer.CA (666) writes "As mentionted on Slahdot previously, there is a proposal to remove leap seconds from UTC (nee 'Greenwich' time). It wil be put to a vote to ITU member states, and if 70% agree, the leap second will be eliminated by 2013. There is some debate as to whether this change is a good or bad idea. One philosophical point opponents make is that the 'official' time on Earth should match the time of the sun and heavens. People with appliances that blink '12:00' can probably ignore this issue."
Education

+ - Kim Davies Dispels DNS "13 Root Servers" M->

Submitted by
LazloHollyfeld
LazloHollyfeld writes "On the official ICANN blog Australian Internet governance and core infrastructure maven Kim Davies sets the record straight... 'So let's dispel these myths. There are not 13 root servers. What there are is there are many hundreds of root servers at over 130 physical locations in many different countries. There are twelve organisations responsible for the overall coordination of the management of these servers. So where does the 13 number come from?'"
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Displays

+ - Nvidia caugth cheating with Crysis driver->

Submitted by
An anonymous reader writes "IAXtech was recently benchmarking nVidia 8800GT against Crysis. While observing very good performance, the tester reported that the water reflection seemed awkward. Now IAXtech reports that nVidia cheated with the driver to get a better FPS. Worse, renaming crysis.exe to 1234.exe cause a huge 17FPS drop in performance.

http://iax-tech.com/video/3870/38705.htm

That is quite a shame, as everyone can expect Crysis to be a reference benchmark in the forthcoming battle between nVidia 8800GT and AMD HD38x0 chips."

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Software

+ - A phone that tells you what to do

Submitted by
Roland Piquepaille
Roland Piquepaille writes "Researchers from the Palo Alto Research Center (PARC) have developed a software code-named Magitti for the Japanese company Dai Nippon Printing (DNP). When this software is installed on your GPS-enabled mobile phone, Magitti starts to suggest you what to do in your area. You don't need to start a Web search for a restaurant or a movie. Magitti will immediately give you some recommendations based on the time of the day and you past behavior. A deployment is scheduled next year in Japan. But it's unclear if this software will be sold in Europe or in the U.S. But read more for additional details and a picture showing how this recommendation server works."
Technology (Apple)

+ - iPhones Have Higher Text Entry Error Rate: Study->

Submitted by
Tech.Luver
Tech.Luver writes "User Centric, Inc., a Chicago-based usability consultancy, finished a final study examining the user experience of Apple's iPhone. Previously, test participants found the iPhone's touch keyboard overly sensitive despite the iPhone's overall high usability. In this usability study, User Centric compared texting experiences of iPhone owners and non-owners across devices. User Centric collected data from 60 participants who entered specific text messages and completed mobile device tasks. Twenty iPhone owners (had iPhone for at least one month), 20 hard-key QWERTY phone (aka QWERTY) owners, and 20 numeric phone owners (multi-tap texters) all entered six fixed-length text messages on their own phones. Non-iPhone owners also entered six messages on a test iPhone and a phone of another type. The Blackberry was the other phone for numeric users while QWERTYs used a Samsung E300. Texting Errors More Frequent on iPhones than Hard-Key QWERTY and Numeric Phones iPhone owners entered text as rapidly as QWERTY owners on their own phones. However, iPhone owners made significantly more texting errors on their own phone (5.6 errors/message) than both QWERTY owners (2.1 errors/message) and numeric phone owners (2.4 errors/message) on their own phones. ( http://techluver.com/2007/11/14/iphones-have-higher-text-entry-error-rate-compared-to-hard-key-qwerty-phones-study/ )"
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