X-Authentication-Warning:	delorie.com: mail set sender to geda-user-bounces using -f
X-Recipient:	geda-user AT delorie DOT com
X-TCPREMOTEIP:	207.224.51.38
X-Authenticated-UID:	jpd AT noqsi DOT com
Mime-Version:	1.0 (Mac OS X Mail 7.3 \(1878.6\))
Subject:	[geda-user] OT-PL/M
From:	John Doty <jpd AT noqsi DOT com>
In-Reply-To:	<559AC9B8.7020205@sbcglobal.net>
Date:	Mon, 6 Jul 2015 16:37:47 -0600
Message-Id:	<1343E2EB-4A4D-46E0-BD87-FCBD230A1C50@noqsi.com>
References:	<1435510363 DOT 682 DOT 26 DOT camel AT ssalewski DOT de> <20150703030409 DOT 32398 DOT qmail AT stuge DOT se> <CAM2RGhSb=z35RYaJQmh-S4N73ng9WOj4ySmy_05J-7KGdBv8SA AT mail DOT gmail DOT com> <CAOP4iL3VBaS+bJhKJDk=_iuBSjDPY2-pvMdz5zPnf7A_rwD0Jw AT mail DOT gmail DOT com> <20150703191532 DOT GB21182 AT localhost DOT localdomain> <alpine DOT DEB DOT 2 DOT 00 DOT 1507040542390 DOT 6924 AT igor2priv> <20150705021010 DOT 369968038A2C AT turkos DOT aspodata DOT se> <CAM2RGhTRQCA5D=1XB2yELZ47nF9uu247CbJjOrJ82EJMNwPAfw AT mail DOT gmail DOT com> <A762D642-FE18-4EA4-9A55-EDBBB0A830F0 AT noqsi DOT com> <559AC9B8 DOT 7020205 AT sbcglobal DOT net>
To:	geda-user AT delorie DOT com
X-Mailer:	Apple Mail (2.1878.6)
X-MIME-Autoconverted:	from quoted-printable to 8bit by delorie.com id t66MbtmO027605
Reply-To:	geda-user AT delorie DOT com
Errors-To:	nobody AT delorie DOT com
X-Mailing-List:	geda-user AT delorie DOT com
X-Unsubscribes-To:	listserv AT delorie DOT com

On Jul 6, 2015, at 12:32 PM, Girvin R. Herr (gherr375 AT sbcglobal DOT net) [via geda-user AT delorie DOT com] <geda-user AT delorie DOT com> wrote:

> More history:
> In the early 80s, IBM first went to Gary Kildall of CP/M for their IBM-PC DOS.  CP/M did have several PL/M modules (pip for one).  If Gary had not ignored IBM and go sailing instead of meeting with the IBM execs, IBM PC-DOS may have had some PL/M in it.  However, we got ms-dos instead.  As I understand it, Kildall used a DEC PDP minicomputer running a PL/M cross compiler in order to develop CP/M.

Must have been one of the bigger DEC machines. He wrote the PL/M cross compiler in Fortran, and it needed at least a 32 bit machine. PDP-10, PDP-20, or VAX maybe.

> 
> Back then, Intel pushed PL/M for their software development packages.  I used it on several projects in the 80s and ran into it again on a legacy bugfix project in the early 2000s.  By then it was getting difficult to find info on it to refresh my memory.

My encounter was earlier, ’74 and ’75. I ported the 8008 version of the PL/M cross compiler to Multics. It proved to be surprisingly portable code, even to Multics’ eccentric Fortran. The main problem was that it used variables initialized in BLOCK DATA, and the Multics model of static initialization didn’t work well with those: if you ran the compiler twice in the same login, the second run would get the values left over from the first! I had to write a little wrapper in PL/I to reinitialize those, and that also gave me a place to handle command line arguments, which were beyond imagination in portable Fortran. Character and bitfield processing in portable Fortran was CPU-intensive, but Kildall had factored the code well, so the compiler had a small footprint in memory. The complicated Multics billing algorithm was very friendly to CPU-intensive code that didn’t use much memory, so cross-compiling PL/M turned out to be surprisingly cheap on a generally very expensive system.

In ’75 we upgraded our Intellec system to an 8080, and of course we had to upgrade PL/M as well. One application of that system was Jeff Bokor’s bachelor’s thesis, an early digital CCD camera. Jeff went on to be one of the inventors of the FinFET: there are probably hundreds of millions of those in the computer in front of you. 

John Doty              Noqsi Aerospace, Ltd.
http://www.noqsi.com/
jpd AT noqsi DOT com

- Raw text -