Breaking News
Comments
Newest First | Oldest First | Threaded View
<<   <   Page 2 / 3   >   >>
SylvieBarak
User Rank
Rookie
re: Slideshow: A brief history of memory
SylvieBarak   12/5/2012 6:17:53 AM
NO RATINGS
Lest we forget.... ;)

steveDS
User Rank
Rookie
re: Slideshow: A brief history of memory
steveDS   12/4/2012 3:34:15 PM
NO RATINGS
Pictures here: http://vipclubmn.org/Memory.html

steveDS
User Rank
Rookie
re: Slideshow: A brief history of memory
steveDS   12/4/2012 3:06:09 PM
NO RATINGS
Sperry Univac had a drum memory that was ~6 feet in diameter and ~18 inchs wide. Had a head per track so no moving parts except the drum. Because of the large diameter it did not have to rotate very fast to get a high speed at the R/W head

Kristin Lewotsky
User Rank
Blogger
re: Slideshow: A brief history of memory
Kristin Lewotsky   12/3/2012 8:22:05 PM
NO RATINGS
Apparently, I was having an out-of-body experience when I calculated 750 kHz--the actual figure is around 200 Hz. Good catch.

andyzg
User Rank
Rookie
re: Slideshow: A brief history of memory
andyzg   12/1/2012 9:52:59 PM
NO RATINGS
hmmm. in the mid 80ies there was a type of Intel memory that acted as SRAM, but upon power failure was able to write the whole array into EEPROM or Flash cells, in parallel, before power was gone. don't remember the name though...

Jack.L
User Rank
CEO
re: Slideshow: A brief history of memory
Jack.L   12/1/2012 8:58:20 PM
NO RATINGS
Cool article by the way. There were a few technologies I had never heard of.

Jack.L
User Rank
CEO
re: Slideshow: A brief history of memory
Jack.L   12/1/2012 8:55:42 PM
NO RATINGS
I actually "touched" magnetic core memory in the late 80's in a professional capacity. It was used in some Allan Bradley PLCs that were in an industrial plant I worked in as a student engineer. Hard to believe it was still in use as little as 25 years ago in functioning equipment.

Kevin Neilson
User Rank
Manager
re: Slideshow: A brief history of memory
Kevin Neilson   12/1/2012 2:20:54 AM
NO RATINGS
This was really interesting. Good work. I'm dubious of one stat, though: it doesn't seem possible that the magnetic drum rotated at 750,000 rotations per second. In fact, that most definitely can't be true. Sometimes in my HDL code when I use a delay line or Johnson ring I call it a mercury line. It's the same concept. The springs in old reverb units are similar--they're basically FIFOs.

DResnick
User Rank
Rookie
re: Slideshow: A brief history of memory
DResnick   11/30/2012 2:26:53 PM
NO RATINGS
In addition to the magnetic core implementation shown, there were other variations according to the number of wires through each core. There were 2, 3, 4, and 5 wire varieties. In the 2-wire type, all the bits in a row are accessed at the same time. The Control Data Star-100 used this type of memory.

sframboss
User Rank
Rookie
re: Slideshow: A brief history of memory
sframboss   11/29/2012 10:21:45 PM
NO RATINGS
Ferroelectrics, a "new" non-volatile memory technology on today's scene, actually competed for the "core" memory of new processors in the 1950's. See the work of J. R. Anderson of Bell Labs: [ J.R. Anderson, "Ferroelectric Material Storage Element for Digital Computers and Switching Systems." Electrical Engineering, Vol. 71, pp. 916-922, October, 1952. ], Charles S. Pulvari of the Catholic University of America: [ AIEE-IRE '53 (Western) Proceedings of the February 4-6, 1953, Western Computer Conference Pages 140-159, ACM New York, NY, USA ©1953 ], and Dudley A. Buck at MIT: [ Dudley A. Buck, "Ferroelectrics for Digital Information Storage and Switching", Report R-212 a Master's Thesis, May 16, 1952, MIT ]. Their devices used bulk ceramic capacitors, not thin films so they required hundreds or even thousands of volts to switch the capacitors. Something old! Something new!

<<   <   Page 2 / 3   >   >>


EE Life
Frankenstein's Fix, Teardowns, Sideshows, Design Contests, Reader Content & More
Max Maxfield

Creating New Faceplates for Antique Analog Meters
Max Maxfield
40 comments
I've currently got a couple of hobby projects on the go that feature the use of antique analog meters. For example, there's my Inamorata Prognostication Engine and its companion, the ...

EDN Staff

11 Summer Vacation Spots for Engineers
EDN Staff
11 comments
This collection of places from technology history, museums, and modern marvels is a roadmap for an engineering adventure that will take you around the world. Here are just a few spots ...

Glen Chenier

Engineers Solve Analog/Digital Problem, Invent Creative Expletives
Glen Chenier
11 comments
- An analog engineer and a digital engineer join forces, use their respective skills, and pull a few bunnies out of a hat to troubleshoot a system with which they are completely ...

Larry Desjardin

Engineers Should Study Finance: 5 Reasons Why
Larry Desjardin
45 comments
I'm a big proponent of engineers learning financial basics. Why? Because engineers are making decisions all the time, in multiple ways. Having a good financial understanding guides these ...

Flash Poll
Top Comments of the Week
Like Us on Facebook
EE Times on Twitter
EE Times Twitter Feed

Datasheets.com Parts Search

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