20 Oct
2019
20 Oct
'19
1:50 p.m.
It is funny that the most common memory used today is a DRO type memory. The read destroys
much of the charge on a DRAM cell, requiring a write back of the data.
Dwight
________________________________
From: cctalk <cctalk-bounces at classiccmp.org> on behalf of Jon Elson via cctalk
<cctalk at classiccmp.org>
Sent: Sunday, October 20, 2019 10:22 AM
To: Nigel Johnson <nw.johnson at ieee.org>; General at ezwind.net <General at
ezwind.net>; Discussion@ <ezwind.net:On-Topic and Off-Topic Posts cctalk at
classiccmp.org>
Subject: Re: plated wire memory
On 10/20/2019 09:45 AM, Nigel Johnson via cctalk wrote:
I remember an IBM engineer talking about this at our
ham
radio club. The wire was coiled inside a drum and pulses
were sent down the wire. The 'read head' was a magnetic
pickup at the other end of the coil - and access time was
however long it took the pulse to arrive at the other
end. Therefore storage capacity was inversely
proportional to data quantity, however at that time I was
working with 660kB Univac FH330 drums for swapping and the
2-ton Fastrand for 164kB of long-term storage, so it has
to be taken in context!
No, that is acoustic delay line memory, and is a serial
access type of data storage All data is lost if the
equipment is powered down. Plated wire memory is a
random-access type of memory using principles similar to
core memory, except the magnetic material is a magnetic film
plated onto the copper wires. There are a few other forms
of NDRO such as Biax that use cores with two holes in them,
one for the sense/inhibit wire and one for the select wires.
Jon