17 Feb
2008
17 Feb
'08
6:11 p.m.
Hi,
Bubble was very, very expensive, and about that time SRAM was becoming
available. I don't have any complete 7110's left -- Intel took them
all back, but I do have the internals. Inside the various coils was a
garnet "chip" and under a good microscope you can see the Chevrons that
steered the magnetic bubbles.
The problem for the company I worked for at the time was temperature --
at about 0 deg C all the bubbles wandered off. I still clearly remember
the Intel FAE telling me, with great conviction "you still have every
bubble -- none have been lost". My explanantion that that was of little
use -- I don't know which byte or address they belong to was lost on
him.
Steering the little bubbles around was fun -- you could rotate the
majority loop, rotate the all minority loops, and replicate from one
loop to the other. Random access it wasn't...
Because of supposed military uses Intel were REAL serious about security
-- they had to know where they all were, who the customers were etc.
-----Original Message-----
From: cctalk-bounces at classiccmp.org
[mailto:cctalk-bounces at classiccmp.org] On Behalf Of Andrew Burton
Sent: Monday, February 18, 2008 1:42 PM
To: cctalk at classiccmp.org
Subject: Bubble memory devices
Hi,
Whilst waiting for a video to download (I'm still on dial-up)
I decided to have a flick through an issue of 80
Microcomputing. It's issue 10 (October 1980) and inlcudes an
article about the row about whether the US government and/or
patent office should honour copyrights for computer software.
Anyway, on page 46 I stumbled across an interesting article
(called "A Slow Road To Bubble Memories") about bubble
memory. The main bubble memory manufacturers of the time were
Intel Corp., Texas Instruments and Rockwell Int. The article
also mentions that Rockwell had a bubble system, a 256K bit
board, available for $1,800. Meanwhile Intel had a bubble
system in kit form - 7110-1 Magnetic Memory board came with
all control and support circuitry - and sold for $2,000.
What happened to bubble memory? Did it die out due to the
costs, or did people prefer to use cassettes, disks etc. instead?
Regards,
Andrew B
aliensrcooluk at yahoo.co.uk