On Nov 20, 2016 1:54 AM, "Chuck Guzis" <cclist at sydex.com> wrote:
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:
http://bitsavers.trailing-edge.com/pdf/ibm/360/model20/C24-9006-4_260-20_Ct…
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.
--Chuck
Theoretical uses of a /20 aside, the Sperry Rand proposal I scanned claims
that a 418-III is a computer with the equivalent performance of a 360/44 or
/50 at /40 prices. Not cheap but you'd save thousands of $$'s. They offer
a , 9400 (and related hardware) system as an option local machine that can
be geared with/paired to time shared 418-III. The teaches us today what
UNIVAC thought back then was a smaet reasonable alternative config should
the customer not want to spend 418-III money.
You don't get this kind of cross-system comparison from the manuals alone.
Considering how they included only 9000 series brochures in the proposal
binder...perhaps it was done to push the 9000 option as a smart "new-way"
alternative, or because everyone already knew about the 418 series stuff,
less so the 9000. At the end of the proposal is the brochure from the time
sharing partner company. Old Computer World's from the time had a lot of
ads for timesharing services.
Bill