26 May
2005
26 May
'05
4:13 p.m.
Around 1982 or so, an RP-20 showed up at CMU. As I
recall, it stored an entire gigabyte on a pair of
HDAs in a single cabinet.
--Bill
26 May
26 May
4:33 p.m.
William wrote:
Around 1982 or so, an RP-20 showed up at CMU. As I
recall, it stored an entire gigabyte on a pair of
HDAs in a single cabinet.
I'm not sure whether IBM made the HDAs, drives, or perhaps the
entire drive cabinet, but the RP20 subsystem used drives with
an IBM bus/tag interface, attached via a DX20 Massbus-to-IBM-bus/tag
interface, which was a fancy microcoded thing.
There was also a TX20 formatter for IBM bus/tag tape drives; I think
it may have been a DX20 running different microcode.
4:51 p.m.
New subject: Disk Drives
I was a FE on the IBM 7094 in 1963 and 1964. At that time Lockheed (Mountain
View) had an IBM 1301 Disk (56 MB, Moving Head Disk, 156K char/sec) and an
IBM 2320 Drum (830K char/sec) attached to an IBM 7631 Controller connected to
an IBM 7909 Data Channel.
For the 1301 take a look at:
http://www-03.ibm.com/ibm/history/exhibits/storage/storage_1301.html
As you can see, the disks were huge!!!
Lyle
--
Lyle Bickley
Bickley Consulting West Inc.
Mountain View, CA
http://bickleywest.com
"Black holes are where God is dividing by zero"
6:34 p.m.
I used a 70 MB HD back as early as 1976. Cant temember the manuf, but
the disks (there were 3 I think) were about 14" in diameter. I still
have one of the disks, or I should say set of three, down in the
garage and have been thinking about making a clock out of it. Its a
beautiful piece of machined brass and aluminum with a magnetic coating
on it.
On 5/26/05, Eric Smith <eric at brouhaha.com> wrote:
William wrote:
--
Jim Isbell
"If you are not living on the edge, well then,
you are just taking up too much space."
W5JAI
UltraVan #257
CAL - 27 #221
1970 E-Type
1985 XJS
1982 XJ6
Around 1982 or so, an RP-20 showed up at CMU. As
I
recall, it stored an entire gigabyte on a pair of
HDAs in a single cabinet.
I'm not sure whether IBM made the HDAs, drives, or perhaps the
entire drive cabinet, but the RP20 subsystem used drives with
an IBM bus/tag interface, attached via a DX20 Massbus-to-IBM-bus/tag
interface, which was a fancy microcoded thing.
There was also a TX20 formatter for IBM bus/tag tape drives; I think
it may have been a DX20 running different microcode.
7101
days inactive
7102
days old
3 comments
4 participants
participants (4)
-
eric＠brouhaha.com -
jim.isbell＠gmail.com -
lbickley＠bickleywest.com -
wmaddox＠pacbell.net