Interested in UNIVAC 9000 Series (and IBM 360)

william degnan billdegnan at
Sat Nov 19 11:56:20 CST 2016

On Sat, Nov 19, 2016 at 12:49 PM, Jon Elson <elson at> wrote:

> On 11/18/2016 10:17 PM, Chuck Guzis wrote:
>> On 11/18/2016 07:59 PM, Jon Elson wrote:
>> Yes, I think it had to, as it had no adder.  Had to be
>>> incomprehensibly slow.  I guess it would load the memory to an
>>> internal register a piece at a time.
>> The last time I dug around a bit for model 20 software, I was surprised
>> to find that there was not only a FORTRAN, but a PL/I and a COBOL
>> written for the thing.
>> By and large, the only applications that I ever saw were RPG.  I can't
>> begin to imagine how slow a COBOL would be, much less a PL/I.
>> PL/I ??  No, I really can't believe it!  Was this a cross-compiler?
> Remember, MANY /20s had 4K memory and no disk.  There also was no OS, so no
> file system support.  I can imagine a cross-compiler being of some use, as
> small programs ought to work OK.  The only sensible reason for FORTRAN
> would be scientific computing, and since the /20 had no floating point, I
> can barely imagine how slow a double precision FP multiply would be.  I
> would have to guess close to a second!  I think a Monroematic calculator
> could give it good competition, and some of the early programmable
> calculators (Wang and such) could almost certainly outdo it.
> I'd rather be hitting myself on the head with a hammer than try to do
> serious computing on a 360/20.
> It makes even a PDP-8 look like a real workhorse.
> Jon

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.

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