Interested in UNIVAC 9000 Series (and IBM 360)

Chuck Guzis cclist at
Sun Nov 20 00:53:40 CST 2016

On 11/19/2016 09:56 AM, william degnan wrote:

> True, but for all that I have read about the actual use of the /20
> that was not what it was for. IBM used the /20's as a smart terminal
> and that kind of thing.    The thing in between the mainframe and
> something else operating in a remote location, and so on.

The Model 20 could use 2311 disks (model 11 or 12) as well as the 2415
tape drive.  And there *was* a disk operating system of sorts:  DPS:

Even has S/360 type JCL--and note that PL/I is mentioned.  Incredible.

One wonders how many "loaded" Model 20 systems were deployed.  An awful
lot were sold as unit-record system replacements.

If you had a disk, IBM really tried to squeeze things small.  DOS/360,
IIRC, could be shoved into a resident with no more than 8KB.  Lots of
transient phases, though.


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