28 Oct
2014
28 Oct
'14
6:46 p.m.
On 2014-10-28 13:42, Clem Cole <clemc(a)ccc.com> wrote:
Cool. I knew CMU did a lot of things with 11/40 machines. I didn't know
they had modified them to be able to write their own microcode, but
thinking about it, it should have been obvious. As they did
multiprocessor systems based on the 11/40, they would have had to modify
the microcode anyway.
Yurg... The MARK instruction was just silly. I never knew of anyone who
actually used it. Rumors have it that DEC just came up with it to be
able to extend some patent for a few more years related to the whole
PDP-11 architecture.
Clem Cole<clemc(a)ccc.com> wrote:
I picked up four 11/60 machines from a place in the late 80s. I still
have a complete set of CPU cards, but threw the last machine away about
10 years ago.
I had a 60 running v7 years later. we also toyed with
adding CSV/CRET
but never did it because we got an 11/70
> >On Oct 27, 2014, at 9:09 PM, Dave Horsfall<dave(a)horsfall.org> wrote:
> >
>> >>On Mon, 27 Oct 2014, Clem Cole wrote:
>> >>
>> >>[...] because the CMU 11/40E had special CSV/CRET microcode which we
>> >>could not use on the 11/34.
> >
> >The 40E had microcode whilst the vanilla 40 didn't? I thought only the 60
> >was micro-programmable; I never did get around to implementing CSV/CRET on
> >our 60 (Digital had a bunch of them when a contract with a publishing
> >house fell through).
DEC actually made two PDP-11s that were micro programmable. The 11/60
and the 11/03 (if I remember right). DEC never had microprogramming for
the 11/40, but obviously CMU did that.
Ronald Natalie<ron(a)ronnatalie.com> wrote:
>On Oct 27,
2014, at 10:06 PM, Clem Cole<clemc(a)ccc.com> wrote:
>
>yes:http://repository.cmu.edu/cgi/viewcontent.cgi?article=3241&context=compsci
<http://repository.cmu.edu/cgi/viewcontent.cgi?article=3241&context=compsci>
>
>I had a 60 running v7 years later. we also toyed with adding CSV/CRET but never did
it because we got an 11/70
Problem with the 60 was it lacked Split I/D (as did the
40's). We kind of relied on that for the kernels towards the end of the PDP-11
days,
We struggled with the lack of I/D on the 11/34 and 11/23 at BRL but finally gave up when
TCP came along. We just didn't have enough segments to handle all the overlaying
needed to do. I recycled all the non split-I/D machines into BRL GATEWAYS.
Of course, there was the famous (or imfamous) MARK instruction. This thing was sort of
a kludge, you actually pushed the instruction on the stack and then did the RTS into the
stack to execute the MARK to pop the stack and jump back to the caller. I know of no
compiler (either DEC-written or UNIX) that used the silly thing. It obviously
wouldn't work in split I/D mode anyhow. Years later while sitting in some DEC
product announcement presentation, they announced the new T-11 chip (the single chip
PDP-11) and the speaker said that it supported the entire instruction set with the
exception of MARK. Me and one other PDP-11 trivia guy are going "What? No mark
instruction?" in the back of the room. >Problem
with the 60 was it lacked Split I/D (as did the 40's).
?A problem was that it was 40 class processor and as you says that means it
was shared I/D (i.e. pure 16 bits) - so it lacked the 45 class 17th bit.
The 60 has went into history as the machine that went from product to
"traditional products" faster than any other DEC product (IIRC 9 months).
I'm always surprised to hear of folks that had them because so few were
actually made. I've forgotten the details nows, but they also
had some issues when running
UNIX. Steve Glaser and I chased those for a long time. The 60 had the HCM
instruction sequences (halt a confuse microcode) which were some what
random although UNIX seemed to hit them. DEC envisioned it as a commercial
machine and added decimal arithmetic to it for RSTS Cobol.? I'm not sure
RSX was even supported on it.
RSX-11M supports it. So do RSTS/E and RT-11. RSX-11M-PLUS obviously
don't, since it have a minimal requirement of 22-bit addressing.
The microcode specific instructions are interesting. But in general
shouldn't crash things, but of course kernel is a different story. :-)
Johnny
28 Oct
28 Oct
6:57 p.m.
New subject: 11/40E and 11/60 (was: speaking of early C compilers)
I picked up four 11/60 machines from a place in the late 80s. I still have a complete set
of CPU cards, but threw the last machine away about 10 years ago.
Chuckle. My wife would kill me. I finally got rid of the ASR-37 (you know a real UNIX
teletype complete with a big NEWLINE key and able to interpret those ESC-8 and ESC-9
things that nroff outputs by default) decades ago (RS tells me he left it blocking
someone's car in at Sprint or something, I disavow all knowledge of it).
While at BRL I was the king of the surplus PDP-11. Any time a PDP-11 came up surplus I
recycled it into internet routers. Sometimes I took the older machines for either their
RK05 or RL02 drives, or just the racks. I got a call up from surplus people asking me
about this $100,000 worth of computer equipment I had turned in and needed to come over
and identify.
What $100,000 worth of computer equipment?
It says here "One PDP-11/40 and accessories."
That thing is 16 years old. That's the price the government paid for it then. Do
you know how much a 16 year old computer is worth?
(especially one that had been stripped of just about everything but the CPU box itself).
6:58 p.m.
New subject: 11/40E and 11/60 (was: speaking of early C compilers)
Found a manual for the WCS for the
11/03...http://bitsavers.trailing-edge.com/pdf/dec/pdp11/1103/EK-KUV11-TM_L…
Amusing reading
7:22 p.m.
New subject: 11/40E and 11/60 (was: speaking of early C compilers)
On Tue, Oct 28, 2014 at 1:46 PM, Johnny Billquist <bqt(a)update.uu.se> wrote:
DEC actually made two PDP-11s that were micro
programmable. The 11/60 and
the 11/03 (if I remember right). DEC never had microprogramming for the
11/40, but obviously CMU did that.
C.mmp was 11/40E's and C.m* was LSI/11's and both needed them for the
capabilities support. I never really got to mess with the WCS units -
although we learned about them (along with ISPL/ISPS in courses), I did
hack on the OS and in user space of both systems - which was a wonderful
experience. It was how I learned about capabilities which I still have soft
spot. But around that time, I was also introduced to this strange new
system language and system and started to get paid better as a programmer
for a group using it. I never went back ;-)
As an a side, Wulf's dedication in the Hydra (C.mmp's OS) Book: "To the
designers and builders of *real* programming systems."
BTW: the 780 & 750 had ustore but it was not user documented and the tools
were internal. Paul Guilbo wrote much of both and later would write the
uCode for the Masscomp FPU and APU. Paul was bitching about the great
tool(s) they had had at DEC, so one weekend two of us on the SW team got
sick of his bitching a couple of us hacked up a uCode assembler in the same
key in Yacc/lex/C (not BLISS ;-).
Later when a couple of ex-PRISM guys started a firm in California there was
an underground trade (i.e. no management knew about it). We were both
using the same EE/CAD systems and we traded them some libraries for our
uCode tools.
Clem
7:39 p.m.
New subject: 11/40E and 11/60 (was: speaking of early C compilers)
On Oct 28, 2014, at 2:22 PM, Clem Cole
<clemc(a)ccc.com> wrote:
BTW: the 780 & 750 had ustore but it was not user documented and the tools were
internal. Paul Guilbo wrote much of both and later would write the uCode for the
Masscomp FPU and APU. Paul was bitching about the great tool(s) they had had at DEC, so
one weekend two of us on the SW team got sick of his bitching a couple of us hacked up a
uCode assembler in the same key in Yacc/lex/C (not BLISS ;-).
Apparently they were at least advertised as available for the 780.
http://h18000.www1.hp.com/info/SP2509/SP2509PF.PDF
8:03 p.m.
New subject: 11/40E and 11/60 (was: speaking of early C compilers)
That SPF shows a date of 1987. Masscomp was '83 for the FP and 84 for the
APU and I know we could not get them - but then again KO was mad at us. At
that point we had more of the 780 HW guys then DEC did, plus a bunch of
ex-VMS and ex-LDP folks. The nasty-gram letter from Ken was framed and
hung out the office of one of the VPs (I wonder if Palmer of one of the
other Masscomp pack rats still has a picture of it).
I know we tried to get it for our Vax, and it was a clear - no way.
On Tue, Oct 28, 2014 at 2:39 PM, Ronald Natalie <ron(a)ronnatalie.com> wrote:
On Oct 28, 2014, at 2:22 PM, Clem Cole <clemc(a)ccc.com> wrote:
BTW: the 780 & 750 had ustore but it was not user documented and the tools
were internal. Paul Guilbo wrote much of both and later would write the
uCode for the Masscomp FPU and APU. Paul was bitching about the great
tool(s) they had had at DEC, so one weekend two of us on the SW team got
sick of his bitching a couple of us hacked up a uCode assembler in the same
key in Yacc/lex/C (not BLISS ;-).
Apparently they were at least advertised as available for the 780.
http://h18000.www1.hp.com/info/SP2509/SP2509PF.PDF
11:54 p.m.
New subject: 11/40E and 11/60
On 2014-10-28 20:03, Clem Cole wrote:
That SPF shows a date of 1987. Masscomp was '83
for the FP and 84 for
the APU and I know we could not get them - but then again KO was mad at
us. At that point we had more of the 780 HW guys then DEC did, plus a
bunch of ex-VMS and ex-LDP folks. The nasty-gram letter from Ken was
framed and hung out the office of one of the VPs (I wonder if Palmer of
one of the other Masscomp pack rats still has a picture of it).
I know we tried to get it for our Vax, and it was a clear - no way.
That SPD is from 1987, true. But that is for version 3.0...
I know that the user microcode option for the 11/780 is really much
older than that. But I wonder how many actually ever purchased it?
Johnny
On Tue, Oct 28, 2014 at 2:39 PM, Ronald Natalie <ron(a)ronnatalie.com
<mailto:ron@ronnatalie.com>> wrote:
--
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: bqt(a)softjar.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
On Oct 28, 2014, at 2:22 PM, Clem Cole
<clemc(a)ccc.com
<mailto:clemc@ccc.com>> wrote:
BTW: the 780 & 750 had ustore but it was not user documented and
the tools were internal. Paul Guilbo wrote much of both and
later would write the uCode for the Masscomp FPU and APU. Paul
was bitching about the great tool(s) they had had at DEC, so one
weekend two of us on the SW team got sick of his bitching a couple
of us hacked up a uCode assembler in the same key in Yacc/lex/C
(not BLISS ;-).
Apparently they were at least advertised as available for the 780.
http://h18000.www1.hp.com/info/SP2509/SP2509PF.PDF
11:48 p.m.
New subject: 11/40E and 11/60
On 2014-10-28 19:22, Clem Cole wrote:
On Tue, Oct 28, 2014 at 1:46 PM, Johnny Billquist <bqt(a)update.uu.se
<mailto:bqt@update.uu.se>> wrote:
DEC actually made two PDP-11s that were micro programmable. The
11/60 and the 11/03 (if I remember right). DEC never had
microprogramming for the 11/40, but obviously CMU did that.
C.mmp was 11/40E's and C.m* was LSI/11's and both needed them for the
capabilities support. I never really got to mess with the WCS units -
although we learned about them (along with ISPL/ISPS in courses), I did
hack on the OS and in user space of both systems - which was a wonderful
experience. It was how I learned about capabilities which I still have
soft spot. But around that time, I was also introduced to this strange
new system language and system and started to get paid better as a
programmer for a group using it. I never went back ;-)
Yeah, it was the C.mmp I was thinking of when I said that CMU obviously
had to have been playing at this.
BTW: the 780 & 750 had ustore but it was not user
documented and the
tools were internal. Paul Guilbo wrote much of both and later would
write the uCode for the Masscomp FPU and APU. Paul was bitching about
the great tool(s) they had had at DEC, so one weekend two of us on the
SW team got sick of his bitching a couple of us hacked up a uCode
assembler in the same key in Yacc/lex/C (not BLISS ;-).
:-)
As someone else mentioned, the 11/780 had a separate product for user
written microcode. I think it actually also included a different board
for the CPU, with more memory for the microcode. So it must have been
documented externally somehow, somewhere.
The 11/750 was not documented for external use, I think. However, I have
some vague memory of seeing something about user written microcode for
it as well.
And of course, Ultrix had a microcode patch for the 11/750, which fixed
some bugs in a couple of instructions. This microcode patch is still
included in the NetBSD/vax distribution. :-)
The 86x0 machines always loaded microcode from the FE RL02, and there is
documentation on that microcode available today, although it was DEC
internal at the time. And I still happen to have access to an 8650. But
no time to actually try and play with the microcode. And that machine is
rather complex as well. That's when things started to get pipelined and
other stuff that makes things much more difficult to fool around with.
Johnny
--
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: bqt(a)softjar.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
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