Breaking News
Comments
Newest First | Oldest First | Threaded View
Page 1 / 2   >   >>
David Ashton
User Rank
Author
Re: Gap
David Ashton   6/10/2014 8:53:11 PM
NO RATINGS
@Zeeglen we need a link under each post "Report as spam" so the webmasters can delete these lowlifes' accounts.....

zeeglen
User Rank
Author
Re: Gap
zeeglen   6/10/2014 7:44:01 PM
NO RATINGS
@johnny john

Again the slimey spamsters come slithering out from under their rocks

kumar_kgp
User Rank
Author
Memory's Evolution: From Stone Tablets to Electronic Ones
kumar_kgp   12/20/2013 7:28:35 AM
NO RATINGS

If you are going back to writing on stone (or clay tablets), you cannot ignore Delay line memory, including Mercury delay lines.

Delay lines were developed to store radar blips so that screens displayed only new, moving blips. In computers, delay lines converted data bits (ones and zeros) into sound waves, transmitted them acoustically, then converted them back into bits. They circulated forever until changed by the computer.

As well as complicating the architecture and programming of a computer using Mercury Acoustic Delay Lines, the mercury filled tubes were non standard components that had to be handled very carefully; they were bulky and had to be kept under close temperature control. Some feel of the mechanics of using them can be gained from looking at the description of the building of EDVAC, about 40% down the page (a chapter from a monograph on the history of Electronic Computers within the Ordnance Corps, written in 1961). EDVAC was the official U.S. successor to the ENIAC, with the design finalised in 1947; but it didn't start to work usably till late 1951 -- "by early 1952 it was averaging 15-20 hours of useful time per week".

Delay line memory was far less expensive and far more reliable per bit than flip-flops made from tubes, and yet far faster than a latching relay. It was used right into the late 1960s, notably on British commercial machines like the LEO I, Highgate Wood Telephone Exchange, and various Ferranti machines.

The principal internal storage in the Univac I system was the 1000-word acoustic delay-line memory.

 

jharasyn554
User Rank
Author
History of memory
jharasyn554   11/19/2013 3:14:16 PM
NO RATINGS
One more item to ad to your list: magnetic core memories. Back in the lates 60's, computers had magentic corememories, the cores strung amid an array of x-y wires that controlled its activation and reading response. similar designs were used in military aircraft at the time; all done on 1k and 2k of memory.

BrainiacV
User Rank
Author
Re: SI binary prefixes
BrainiacV   11/18/2013 10:31:41 AM
NO RATINGS
Cool!  I didn't know that.  I've just come to hate the marketers who thought to inflate spec numbers by using decimal rather than binary for their drive size measurement.  You don't see them doing tht for RAM, just hard drives, from what I've seen.  I'm always having to explain to friends and relatives why their hard drive did not format to the size they expected.

Paul A. Clayton
User Rank
Author
Re: Data Access and Longevity
Paul A. Clayton   11/17/2013 4:42:40 PM
NO RATINGS
"A key parameter that isn't discussed is the likely life expectancy of the stored data. Clearly #1 (stone) wins hand down."

In addition to the life expentancy of the raw data, knowledge of the format is also important. This requires some continuity of knowledge. Even older forms of storage encounter a similar issue; writings in dead languages can be very difficult to understand.

(As you pointed out, even data that is physically readable may be uneconomical to read because of the cost of the reading device.)

#1 is actually clay not stone, by the way.

Paul A. Clayton
User Rank
Author
SI binary prefixes
Paul A. Clayton   11/17/2013 3:50:34 PM
NO RATINGS
Mebi is the SI binary prefix for 2 to the 20th power (i.e., 1,048,576). Mega is only 1,000,000.

http://physics.nist.gov/cuu/Units/binary.html lists some of the SI binary prefixes and some background information.

DrQuine
User Rank
Author
Re: Data Access and Longevity
DrQuine   11/16/2013 9:51:04 PM
NO RATINGS
My sense is that other than cars, almost nothing is improving in longevity and maintainability. Cars certainly last much longer than they used to and require much less maintenance. Almost all repairs, however, require a skilled mechanic. Even replacing a headlight on my wife's VW requires removing the windshield washer and annoying little repairs to the electrical components can be exceptionally expensive. Electronic devices like televisions have longer life expectancies than their tubed ancestors - but repairs are typically cost prohibitive.

JeremySCook
User Rank
Author
Re: Data Access and Longevity
JeremySCook   11/16/2013 9:34:03 PM
NO RATINGS
I hadn't thought about that aspect.  That is very interesting how that works.  Maybe it's not just memory - things are getting easier and easier to manufactuure, but in some cases aren't built for nearly as long a life.

David Ashton
User Rank
Author
Re: Data Access and Longevity
David Ashton   11/16/2013 9:11:59 PM
NO RATINGS
@DrQuine.  What you're saying is that as we go on we are getting more, but shorter term, memory.  Sound's like Altzheimers to me......

Page 1 / 2   >   >>


Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
Radio
NEXT UPCOMING BROADCAST

What are the engineering and design challenges in creating successful IoT devices? These devices are usually small, resource-constrained electronics designed to sense, collect, send, and/or interpret data. Some of the devices need to be smart enough to act upon data in real time, 24/7. Are the design challenges the same as with embedded systems, but with a little developer- and IT-skills added in? What do engineers need to know? Rick Merritt talks with two experts about the tools and best options for designing IoT devices in 2016. Specifically the guests will discuss sensors, security, and lessons from IoT deployments.
Like Us on Facebook
Special Video Section
The quality and reliability of Mill-Max's two-piece ...
01:34
The quality and reliability of Mill-Max's two-piece ...
LED lighting is an important feature in today’s and future ...
05:27
The LT8602 has two high voltage buck regulators with an ...
05:18
Silego Technology’s highly versatile Mixed-signal GreenPAK ...
The quality and reliability of Mill-Max's two-piece ...
01:34
Why the multicopter? It has every thing in it. 58 of ...
Security is important in all parts of the IoT chain, ...
Infineon explains their philosophy and why the multicopter ...
The LTC4282 Hot SwapTM controller allows a board to be ...
This video highlights the Zynq® UltraScale+™ MPSoC, and sho...
Homeowners may soon be able to store the energy generated ...
The LTC®6363 is a low power, low noise, fully differential ...
See the Virtex® UltraScale+™ FPGA with 32.75G backplane ...
Vincent Ching, applications engineer at Avago Technologies, ...
The LT®6375 is a unity-gain difference amplifier which ...
The LTC®4015 is a complete synchronous buck controller/ ...
10:35
The LTC®2983 measures a wide variety of temperature sensors ...
The LTC®3886 is a dual PolyPhase DC/DC synchronous ...
The LTC®2348-18 is an 18-bit, low noise 8-channel ...