Subject: Re: pdp-8 and pdp-11 simulators

From: [email-masked]
Date: 30 Sep 94 14:03:40 MDT

In article <[email-masked]>, [email-masked] (Megan) writes:
> 	[ed. - the OS8 and RT11 disks are not available due to
> 	 licensing issues ... if you have a disk, simply copy
> 	 the disk to an image file and use that.]

Given that DEC gave OS/78 and OS/278 to the DECUS library, I doubt there
would be any problems distributing OS/8 disks.
-- 
----------------+------------------------------------------------------
Roger Ivie      | Don't think of it as a 'new' computer, think of it as
[email-masked] |     'obsolete-ready'

---

From: [email-masked] (Megan)
Date: Fri, 30 Sep 1994 17:55:30 GMT

>One point isn't clear to me: How do you get a file named rt11.dsk on your 
>vax? I have a rt11-floppy, that I can read and put into a a sub-dir.

Use RT-11 to copy the device to a file (COPY/DEV/FILE dev: file.dsk) and
then transfer the file in image mode to the vax.  There may be a simpler
way using exchange or some other VMS utility, but I'm not a VMS expert...

					Megan Gentry
					Former RT-11 Developer

---

From: [email-masked]
Date: 30 Sep 94 13:18:45 -0600

In article <[email-masked]>, [email-masked] (James Williams) writes:

> Will these run under Ultrix-11 on an 11/83?  ;^))

Now THERE'S an exersize in futility.  Run ULTRIX on a PDP11, and then run a
PDP11 simulator.  Nothing like using a PDP11 to simulate a PDP11.

-- 
===============================================================================
[                    Fermi National Accelerator Laboratory                    ]
===============================================================================
[ Mark E. Levy, N9RXF             |					      ]
[ BitNet:      LEVY@FNAL          |       Unix: The only computer virus       ]
[ Internet:    [email-masked]      |             with a user interface.        ]
[ HEPnet/SPAN: FNAL::LEVY (VMS!)  |             (such as it is...)            ]
===============================================================================

---

From: [email-masked] (James Williams)
Date: 30 Sep 1994 17:56:04 GMT

/s/ Jim WIlliams

---

From: [email-masked] (James Williams)
Date: 30 Sep 1994 17:56:04 GMT

/s/ Jim WIlliams

---

From: [email-masked] (Eberhard Heuser-Hofmann)
Date: 30 Sep 1994 17:05:27 GMT

In article <[email-masked]>, [email-masked] (Megan) writes:
|>
|>After getting permission from the author, I have placed a compressed
|>tar file containing a pdp8 and pdp11 simulator in my ftp area on the
|>world.  The file is obtainable from:
|>
|>	ftp.std.com:/ftp/pub/mbg/pdp_simulators.tar.Z
|>
|>I have used the pdp-11 simulator on a VAX running ultrix, a MIPS R4000
|>running ultrix and an Alpha running DEC OSF/1 V1.3 and V2.0 and have
|>successfully booted RT-11 (V5.6), some flavor of RSX and some flavor
|>of RSTS (I think it was V9.2).
|>
|>Enjoy!
|>
|>					Megan Gentry
|>					Former RT-11 Developer
|>
|>The 0readme.txt file follows:
|>
|>The following is the original 'announcement' of the availablility of the
|>pdp8 and pdp11 simulators to a private list.  It has been edited to
|>remove certain sensitive pieces of information:
|>
|>- - - - -
|>
|>I am pleased to announce the (internal field test) for the PDP-8 and
|>PDP-11 simulators.  To get the sources and the simulated OS8 and RT11
|>disks, copy xxxxxx to your system and proceed as outlined in these notes.
|>Sketchy documentation on the simulators is in file 0simdoc.txt
|>	[ed. - the OS8 and RT11 disks are not available due to
|>	 licensing issues ... if you have a disk, simply copy
|>	 the disk to an image file and use that.]
|>
|>1. The simulators work on both VAX/VMS and on Alpha/OSF1.
|>	[ed. - and on mips/ultrix]
|>
|>2. Each simulator includes a CPU, memory, reader, punch, terminal, line
|>   clock, RK05 disk, and RX01 disk.  (The PDP-8 has an RF08, and the
|>   PDP-11 has an RL11.)
|>
|>3. There's a VMS build file for each simulator:
|>
|>	pdp8_build	builds PDP8.EXE
|>	pdp11_build	builds PDP11.EXE
|>
|>	[ed. - A preliminary Makefile is provided which will build
|>	 the simulators, but may not be as concise or as full-purpose
|>	 as it could be]
|>
|>   The build files include the debugger, remove that if you want.
|>
|>   For OSF/1, the build command lines are:
|>
|>	cc pdp8*.c scp*.c -lm -o pdp8
|>	cc pdp11*.c scp*.c -o pdp11
|>
|>4. The simulators are only partially tested.
|>
|>   I would APPRECIATE YOUR FEEDBACK.  Feel free to try small programs
|>   to test the EAE, FP11, and devices.  If you find bugs, feel free to
|>   look through the sources and send me the fixes...:-)
|>
|>	[ed. - The author has set up a mail alias to receive such
|>	 mail.  You can send mail to him at [email-masked]]
|>
|>5. To get the simulated operating systems up and running (OSF/1 shown):
|>
|>	% pdp8
|>
|>	PDP-8 simulator V1.0
|>	sim> att rk0 os8.dsk
|>	sim> boot rk0
|>
|>	. <-- OS/8 prompt
|>
|>   This is pretty much instantaneous on either VAX or Alpha.  You
|>   must first set the date (note that OS/8 REQUIRES CAPITAL LETTERS
|>   FOR INPUT) and then you can type HELP or DIR to explore further:
|>
|>	.DA 14-MAR-94
|>
|>	.DIR
|>
|>   For the PDP-11 and RT11:
|>
|>	% pdp11
|>
|>	PDP-11 simulator V1.0
|>	
|>	sim> att rk0 rt11.dsk
|>	sim> boot rk0
|>
|>	RT11SJ (S) V5.04
|>
|>	.
|>	. <-- RT11 prompt
|>
|>   Note that on a slow VAX (eg, a 3100) it takes 45 seconds to get to
|>   the banner, and another 15-20 seconds to get to the prompts.  On
|>   Alpha/OSF1, it takes a few seconds to reach the prompt.  You can
|>   then set the date, type HELP or DIR, and so on.  RT11 accepts lower
|>   case input.
|>
|>   The simulator is stopped by typing ^E (control-E).  This can be
|>   changed through the WRU register.
|>
|>

Megan,

One point isn't clear to me: How do you get a file named rt11.dsk on your vax?
I have a rt11-floppy, that I can read and put into a a sub-dir.

Eberhard

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From: [email-masked] (Megan)
Date: Fri, 30 Sep 1994 17:49:55 GMT

I failed to properly credit Bob Supnik for his work on the emulators.

Because he had the mail alias for reporting bugs, I figured he wanted to
be anonymous to some extent, forgetting his name is in the sources...

Anyway, he deserves the credit for writing these wonderful simulators.

					Megan Gentry
					Former RT-11 Developer

---

From: [email-masked] (John Wilson)
Date: 1 Oct 1994 14:43:29 GMT

In article <[email-masked]>,
>In article <[email-masked]>, [email-masked] (Megan) writes:
[quotes entire article including long readme file]

DON'T DO THAT!!!  Cut out the parts of the article you aren't referring to.
In this case you weren't referring to anything.

>I have a rt11-floppy, that I can read and put into a a sub-dir.

If you have a working PDP-11 then Megan's answer (make it on the 11) is
definitely the easiest.  Otherwise I'm working on a program (only the RT-11
part is finished) which can read images of RT-11 disks (getting those into
your PC is still your problem unless they're RX50s, which it can read/write/
format directly) and knows how to write a primary and secondary RT-11
bootstrap for any device (i.e. emulates COPY/BOOT), so you can do things
like building an RK05 or RL01 boot pack from an RX50 distribution (or RX01
with an 8" FDC) w/o having a PDP-11.  Of course if you have no PC this is
no help...

John Wilson

---

From: [email-masked] (Megan)
Date: Sat, 1 Oct 1994 03:58:49 GMT

[email-masked] (John Crowell) writes:

>James Williams ([email-masked]) wrote:
>: Will these run under Ultrix-11 on an 11/83?  ;^))

>Hey, great idea Jim!
>Then we could run SYSSIM on RT-11 under the PDP-11 emulator
>in order to simulate an UNIX environment!!

Why not the pdp-11 emulator running under ultrix, booting a disk with
ultrix-11 ... :-)

					Megan

---

From: [email-masked] (Kenn Goutal)
Date: Sun, 2 Oct 1994 05:16:51 GMT

In article <[email-masked]>,
>in order to simulate an UNIX environment!!

In the early 70's, a friend of mine wrote a 64k PDP-11 simulator
that ran on an 8k PDP-8 (actually PDP-12) with RK05 (I think).
There was in DECUS a PDP-8 simulator that ran on the PDP-10.
We used to joke about simulating an -11 on the simulated -8 on a -10.
Never did it, though.

---

From: [email-masked] (Megan)
Date: Sat, 1 Oct 1994 03:57:34 GMT

>/s/ Jim WIlliams

Hi, Jim ...

Don't know, haven't tried, yet.  The problem I've had with even running
it on a MicroVAX running Ultrix is the c compiler doesn't like
the prototyping.  I've had one (1, uno, ichi...) success building it
using vcc under vax/ultrix, but I've never been able to duplicate it.

Personally, I've wanted to do something like run OS/8 under the pdp-8
emulator running under RT-11 on an emulated 11 running under OSF/1
on an alpha ... talk about approaching the speed of an original -8 ...
from  above :-)

					Megan Gentry
					Former RT-11 Developer

---

From: [email-masked] (John Wilson)
Date: 1 Oct 1994 14:46:35 GMT

In article <[email-masked]>, Megan <[email-masked]> wrote:
>I've had one (1, uno, ichi...) success building it

Are there conditionals for screwy PC Unices like Linux now?  I have a
copy of the emulator that's a few months old and it depended on
#including <sgtty.h>, which Linux doesn't have, plus it got a bunch
of warnings about negative shift counts in the macros in the FPP code.

John Wilson

---

From: [email-masked] (Megan)
Date: Sat, 1 Oct 1994 19:07:15 GMT

>of warnings about negative shift counts in the macros in the FPP code.

	There aren't any conditionals.  Bob tried to do it in a C
	which would be as transportable as possible (which isn't
	really possible, given the nature of the virus known as
	unix ... for more on this see the unix-haters list)

					Megan Gentry
					Former RT-11 Developer

---

From: [email-masked] (Megan)
Date: Sat, 1 Oct 1994 19:08:47 GMT

>Are there conditionals for screwy PC Unices like Linux now?  I have a
                            ------    ------

But then, you repeat yourself... :-)

					Megan

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From: [email-masked] (Sander van Malssen)
Date: Sat, 1 Oct 1994 22:00:24 +0100 (MET)

> of warnings about negative shift counts in the macros in the FPP code.

Try adding -I/usr/include/bsd and -lbsd to the compile flags, that
should get you going. If not, it's usually fairly easy to rewrite the
sgtty stuff into termio or termios stuff. (I did that with both Doug
Jones' and Mr. Haygood's -8 emulators. Haven't had time to look at these
two particular emulators though.)

Sander
-- 
Sander van Malssen
[email-masked]

---

From: [email-masked] (Tom Ivar Helbekkmo)
Date: 3 Oct 94 08:18:34 MET

In article <[email-masked]>, [email-masked] (Sander van Malssen) writes:
> should get you going.

Another thing to beware of is the presence, in one of the header files
(I don't have the source right here, but it's the single common header
file), of explicit stringification.  There are, near the end, about 5
occurences of

	#define SOMETHING(nm, ...) "nm", ...

which may need rewriting.  Using gcc, for instance, it should be

	#define SOMETHING(nm, ...) #nm, ...

You can quickly find out if you need to change this by giving, at the
"sim>" prompt, the "examine pc" command -- if it doesn't work, you need
to fix the stringification to fit your compiler.

-tih

---

From: [email-masked] (Matthias Bruestle)
Date: Sun, 2 Oct 1994 10:48:17 GMT

Mahlzeit

> on an alpha ... talk about approaching the speed of an original -8 ...
Can you tell me, how fast the pdp-8 is? How many instuctions per
second? Or compared to a Z80? (SPECint? :) )

				Mahlzeit

-- 
A leap ahead... through insanity.

---

From: [email-masked] (John Wilson)
Date: 3 Oct 1994 02:27:34 GMT

In article <[email-masked]>,
>second? Or compared to a Z80? (SPECint? :) )

As always, It Depends.  My understanding from the docs is that the PDP-8/E
takes 1.2 usec per normal core memory cycle (read/write), or 1.4 usec if
there's an increment between the read and write (ISZ instruction and/or
autoindexing locations).  So just count up the memory cycles and that should
give you the execution time for the instructions.  IOTs can be really slow
since there are wait states for devices on the posibus (if you have one).
Also data break (DMA) costs cycles, obviously.

All other PDP-8 models are slower, by varying amounts.  The 8/S is a real dog.

John Wilson

---

From: [email-masked] (Douglas W. Jones,201H MLH,3193350740,3193382879)
Date: 3 Oct 1994 15:20:33 GMT

From  article <[email-masked]>,
by [email-masked] (Matthias Bruestle):

> second?

If you have access to WWW, you can pick the instruction timings out of the
pocket reference cards available on

   http://www.cs.uiowa.edu/~jones/pdp8/index.html

In short, on the classic PDP-8, the memory cycle time was 1.5 microseconds,
and instructions took either:

   1 cycle -- such things as: two's complement accumulator
                              1 or 2 place shift the accumulator
                              skip next instruction if accumulator zero
                              branch

   2 cycles -- memory reference instructions such as: add to accumulator,
                                                      procedure call,
                                                      indirect branch.

   3 cycles -- indirect memory reference instructions, including autoincrement
                 indirect addressing.

On the PDP-8/E, the memory cycle was either 1.2 or 1.4 microseconds;
generally, indirect cycles were short, unless they involved autoincrement
addressing, fetch cycles were short, and execute cycles were long.

				Doug Jones
				[email-masked]

---

From: [email-masked] (Megan)
Date: Sat, 1 Oct 1994 04:00:09 GMT

>would be any problems distributing OS/8 disks.

I'll let someone else do that ... for OS/*8

Isn't it already available from ftp.update.uu.se?

					Megan Gentry
					Former RT-11 Developer

---

From: [email-masked]
Date: 30 Sep 94 23:26:49 MDT

> Isn't it already available from ftp.update.uu.se?

Yes, but not in a version bootable with this simulator.
-- 
----------------+------------------------------------------------------
Roger Ivie      | Don't think of it as a 'new' computer, think of it as
[email-masked] |     'obsolete-ready'

---

From: [email-masked] (Johnny Billquist)
Date: 3 Oct 1994 17:51:48 +0100

>Isn't it already available from ftp.update.uu.se?

Hmmm. We have OS/278 and Multos on ftp.update, but not OS/8.
While this might seem like a stupid point, DEC really haven't
let go of OS/8 yet, so we will not put it up for distribution.

	Johnny
-- 
Johnny Billquist                  || "I'm on a bus
CS student at Uppsala University  ||  on a psychedelic trip
email: [email-masked]       ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol

---

From: [email-masked] (Dave Mitton)
Date: 3 Oct 1994 16:15:24 GMT

< ...deleted announcment

.. Gee all I need now is an RX02 emulated device, I could run my RT-11 CP/M
emulator.  ;-}

	Dave.  (guess I could get rid of my SB-11 firesale system...)