🚀 go-pugleaf

Charles Richmond <nume...@aquaporin4.com> writes:

> On 8/9/2018 1:45 PM, Rich Alderson wrote:
>> Elliott Roper <nos...@yrl.co.uk> writes:

>>> On 8 Aug 2018, hanc...@bbs.cpcn.com wrote
>>> (in article<21aaeee8-c41a-4442...@googlegroups.com>):

>>>> Bitsavers uploaded the system manual for the PDP 11/40.

>>>> http://www.bitsavers.org/pdf/dec/pdp11/1140/DEC-11-H40SA-A-D_PDP-11_40_System_manual.pdf

>>>> 358 pages, undated.

>>> Thanks. Unbounded nostalgia. Was there ever a more elegant computer than a
>>> PDP-11?

>> Yes, many.

> *Not* that I disagree...  but which other computers do you find elegant???

My first computer was the IBM 1401.  *Not* an elegant architecture, but not
without points of interest.

The first I fell in love with was the IBM System/360, thanks to a high school
graduation gift from a sweetheart, Germain's _Programming the IBM 360_.  One of
these days I'm going to put his simulator on Hercules and go through the
exercises just for giggles.

When introduced to the PDP-10, 8 years later, I found it annoying:  No base
register, only a single index register per instruction, so some of my favorite
tricks simply did not work.  No condition codes; what's with all these SKIPx
and JUMPx and Txxx (test) instructions?  And then a miracle happened.

I still think in EBCDIC, nearly 50 years later, rather than ASCII, which I sort
of learned less than 40 years ago, and I still have a fondness for the 360
instruction architecture, but the orthogonality of the PDP-10 instruction set,
the uniform use of bits 7-8 to indicate no-modification/immediate/memory/self
on all the data movement instructions, the elegance of single instructions to
conditionalize the execution path rather than a sequence in which you have to
be careful of changes to the condition codes you're checking, even the word
addressing rather than byte addressing, have forever spoiled me for lesser
systems.

"But that's just my opinion, I could be wrong." --Dennis Miller

-- 
Rich Alderson					  ne...@alderson.users.panix.com
      Audendum est, et veritas investiganda; quam etiamsi non assequamur,
	  omnino tamen proprius, quam nunc sumus, ad eam perveniemus.
									--Galen