10 May
2018
10 May
'18
10:47 a.m.
The fixed head disc used on MU5 had a 20.5ms revolution time and an inner
track data rate of 2.2Mbytes/sec.
Regards
Rob
-----Original Message-----
From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Paul
Koning via cctalk
Sent: 10 May 2018 17:30
To: Grif <grif615 at mindspring.com>
Cc: General Discussion: On-Topic and Off-Topic Posts
<cctalk at classiccmp.org>
Subject: Re: how fast were drum memories?
> On May 10, 2018, at 10:37 AM, Grif <grif615 at mindspring.com> wrote:
>
>
> I wonder how the late generation paging disks (fixed head per track)
like
DG used in the 80's compared?
One that comes to mind is the DEC RS04. It spins at roughly 3600 rpm (a
hair
less, so obviously a 2 pole induction motor running
off 3-phase 60 Hz
power).
Transfer rate is 0.5 megabytes per second, but still,
at that RPM, average
latency is 8.5 ms.
paul