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Installing core backplane into PDP 11/40

Hi Bill;

I just found Your posting of running CKBB, and I have a couple of comments..
First, You didn't let it Run nearly Long enough..
Second, You need to patch address '3604 from an '000007 to a '000052, so it will Print a STAR when it makes a single Pass..
It is easiest to do this from PDPGUI after You have Loaded the program into PDPGUI, but before You Load it into Your 11/40, after You have Patched it using PDPGUi then, Load the 11/40 and it will be ready to Run..
Then Run it on the /40 and WAIT for the Stars to appear on the Screen.. (Assuming everything is OK ).. Give it 3 to 5 minutes per pass, Depending on the Amount of Memory You have in Your machine, and the speed of Your machine.. Maybe longer, since Your Machine is slower than mine..
Also, Note that the First Star Doesn't count, only the Second Star and following.. And that both Fritzm, and I have listed where to find the 'Bell' and where to change it to '000052, and the Bell might be either an '000007 or an '000207..

THANK YOU Marty
 
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I will give it a try. The program ran for at least 30 mins before I stopped it but I will try your patches to see what effect it has, thanks
 
The change worked. It prints an asterisk every few minutes. I am at pass 10 so far. You're right, I was not waiting long enough, and I heard nothing of a bell so I had no idea whether the program was functioning correctly. At this point I am waiting to hear back from Ray who has my RL11 stuff, so I can resume testing the only thing that does not work - actually booting a disk.
 
Hi All;

Bill, Good News !! Congratulations !!

What I would suggest and give a try at, is go thru the Rest of the Tests and Do the same Kind of thing, Change the 'Bell' to a 'Star' And see if any of them Fail or if they all Pass, That way You Know for sure, especially if You run all of the Tests..

THANK YOU Marty
 
I spoke with QBUS by phone today, we were wondering what the minimum RAM requirement is for RT-11 v5. I may need add to the 16K I have installed.

Confirming one way or another about the RAM requirement might shed some light. At least in addition to any additional CPU tests.
 
Hi All;

Good for You, Bill, If You have a MOS Ram Card of more Memory than Your 16K of Core, Throw it in there just for a Test, If that solves the problem, then You know that it is not enough RAM in the System.. And that will hopefully tell You How much Ram is needed, Core or otherwise..
If the problem still persists, then You know that You still need to look elsewhere..

THANK YOU Marty
 
I spoke with QBUS by phone today, we were wondering what the minimum RAM requirement is for RT-11 v5. I may need add to the 16K I have installed.

Confirming one way or another about the RAM requirement might shed some light. At least in addition to any additional CPU tests.

From the RT11 v5.1 system release notes:

Capture.JPG

the RT11SJ monitor will run in 16KW, minimum. The documentation for v5.6 does not specify a minimum memory requirement (other than 28KW) that I can find, and for v5.6 the SJ monitor is renamed/redone as the SB monitor. So unclear at this point if v5.6 SB monitor can run in 16KW.

Earlier v4/v3/v2 RT11 systems could run the single job monitor in as little as 8KW I believe but v5 bumped the minimum to 16KW.

Probably the easiest test would be to configure a PDP-11 to the appropriate memory size in SIMH and trying to boot your test RT11 image.
 
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Found this:

"A minimal but complete system supporting a single real-time user could run on a single floppy disk and in 8K 16-bit words (16KB) of RAM, including user programs. This was facilitated by support for swapping and overlaying. To realize operation on such small memory system, the keyboard command user interface would be swapped out during the execution of a user's program and then swapped into memory upon program termination. The system supported a real-time clock, printing terminal, VT11 vector graphic unit, 16 channel 100 kHz A/D converter with 2 channel D/A, 9600 baud serial port, 16 bit bidirectional boards, etc."
 
I have a 64K MOS RAM board installed in slot 3 of my DD11-CF backplane. Slot 3 is a MUD slot without the NPG jumper removed. The manual says it will work in any MUD slot. It seems to work OK. I ran a memory diagnostic and loaded BASIC.

On the same backplane slot 2 is a MUD slot with the NPG jumper removed. I have had the RL11 controller installed there. The RL11 manual says the M7762 should be installed in a MUD slot with the NPG removed.

I believe I have concluded correctly where to put the MOS and RL11 controllers and that they can be together. Any dissenting opinions?

If replacing the 16K core with the 64K MOS RAM will load RT11, I would conclude that one needs more than 16K installed in the system for version 5 all else being the same.

Bill
 
I have a 64K MOS RAM board installed in slot 3 of my DD11-CF backplane. Slot 3 is a MUD slot without the NPG jumper removed. The manual says it will work in any MUD slot. It seems to work OK. I ran a memory diagnostic and loaded BASIC.

On the same backplane slot 2 is a MUD slot with the NPG jumper removed. I have had the RL11 controller installed there. The RL11 manual says the M7762 should be installed in a MUD slot with the NPG removed.

I believe I have concluded correctly where to put the MOS and RL11 controllers and that they can be together. Any dissenting opinions?

If replacing the 16K core with the 64K MOS RAM will load RT11, I would conclude that one needs more than 16K installed in the system for version 5 all else being the same.

Bill

You should be able to boot any single job monitor - RT11SJ or RT11SB in only 16KW (32KB). You may not be able build your own customized monitor or execute large complies/links without additional memory, but the basic utilities should work.

The memory and controller configuration appears acceptable.

Code:
[FONT=Menlo].sh con[/FONT][FONT=Menlo]
[/FONT]
[FONT=Menlo]RT-11SB  V05.07  [/FONT]
[FONT=Menlo]Booted from DU0:RT11SB[/FONT]
[FONT=Menlo]
[/FONT]
[FONT=Menlo]PDP 11/73A Processor[/FONT]
[FONT=Menlo]32KB of memory[/FONT]
[FONT=Menlo]Floating Point Microcode[/FONT]
[FONT=Menlo]Extended Instruction Set (EIS)[/FONT]
[FONT=Menlo]Memory Management Unit[/FONT]
[FONT=Menlo]Cache Memory[/FONT]
[FONT=Menlo]60 Hertz System Clock                  [/FONT][FONT=Menlo]
[/FONT]
[FONT=Menlo].sh mem[/FONT]

[FONT=Menlo]Address   Module    Words[/FONT]
[FONT=Menlo]-------   ------    -----[/FONT]
[FONT=Menlo]160000    IOPAGE     4096.[/FONT]
[FONT=Menlo]100000    MEMTOP    12288.[/FONT]
[FONT=Menlo]074060    DU         1000.[/FONT]
[FONT=Menlo]054372    RMON       3995.[/FONT]
[FONT=Menlo]001000    ..BG..    11133.[/FONT]
 
This weekend while at HOPE I will set up simh and experiment. I don't believe in my actual 11/40 I have an EIS card installed. I have not used simh for pdp 11 RT11 yet, I only used for other things.

I have never actually used rt11, although it seems similar to Pdp8 OS8. When you say that you can load a job monitor, do you mean "boot" see an OS prompt so I can then run commands? I need to learn more, I assume we were talking "get to the dot prompt".

Because in SIMH for the 11/40 EIS is standard, you CANNOT disable it, (i.e. SET CPU NOEIS), I seriously wonder if this is going to hamper using RT11 even with 64K
 
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This weekend while at HOPE I will set up simh and experiment. I don't believe in my actual 11/40 I have an EIS card installed. I have not used simh for pdp 11 RT11 yet, I only used for other things.

I have never actually used rt11, although it seems similar to Pdp8 OS8. When you say that you can load a job monitor, do you mean "boot" see an OS prompt so I can then run commands? I need to learn more, I assume we were talking "get to the dot prompt".

Because in SIMH for the 11/40 EIS is standard, you CANNOT disable it, (i.e. SET CPU NOEIS), I seriously wonder if this is going to hamper using RT11 even with 64K

For the purpose of discussion here
monitor=operating system
handler=device driver​

So loading a monitor is equivalent to booting the OS.

RT11 was meant to be a small "real time" OS mean for users that needed close access to the hardware. The Single Job - SJ or its successor SB made minimal expectations of the underlying hardware. If you had more memory or memory management features, you could select the included FB or XM monitors. If you were up to customizing things, adding error logging, timeout support or more terminals; this was possible because the bare OS sources were included. You could then compile these features into your own version of the monitor and handlers.

RT11 should not depend on EIS to boot. In SIMH it boots fine off of an emulated 11/20.

Code:
[FONT=Menlo]
[/FONT]
[FONT=Menlo].sh con[/FONT]
[FONT=Menlo]
[/FONT]
[FONT=Menlo]RT-11SB  V05.07  [/FONT]
[FONT=Menlo]Booted from DU0:RT11SB[/FONT]
[FONT=Menlo]
[/FONT]
[FONT=Menlo]USR     is set SWAP[/FONT]
[FONT=Menlo]EXIT    is set SWAP[/FONT]
[FONT=Menlo]KMON    is set NOIND[/FONT]
[FONT=Menlo]MODE    is set NOSJ[/FONT]
[FONT=Menlo]TT      is set NOQUIET[/FONT]
[FONT=Menlo]ERROR   is set ERROR[/FONT]
[FONT=Menlo]SL      is set OFF[/FONT]
[FONT=Menlo]EDIT    is set KED[/FONT]
[FONT=Menlo]FORTRAN is set FORTRA[/FONT]
[FONT=Menlo]KMON nesting depth is 3[/FONT]
[FONT=Menlo]
[/FONT]
[FONT=Menlo]CLI is set DCL, CCL, UCL, NO UCF[/FONT]
[FONT=Menlo]
[/FONT]
[FONT=Menlo]PDP 11/15,20 Processor[/FONT]
[FONT=Menlo]32KB of memory[/FONT]
[FONT=Menlo]60 Hertz System Clock                  [/FONT]
[FONT=Menlo]
[/FONT]
[FONT=Menlo]FPU support[/FONT]
 
that's good to know as my EIS cards both seem to be bad.

Ray has my RL11 boards and stuff, he checked them out they're ok so once they're back here I can try to boot with the MOS / 64K board installed and no EIS (unless I find the problem and fix it)
 
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