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PDP 11/45, Part 3

Hi All;
Here is the first program from the book 'Machine and Assembly Language Programming of the PDP 11'..

BCPL 32-bit Cintcode System (30 May 2013)
0.000> TRIPOS PDP-11 Assembler version 1.4
Calling firstpass()

Calling secondpass()
;Title Backward
;Accept a line of characters fron the Teletype and Echo it Backwards.
000000' LC=.
000004' .=4+LC
000004' 000006 000000 000012 .WORD 6,0,12,0 ; INITIALIZE ERROR VECTORS
000012' 000000
000500' .=500+LC
000500' 010706 START: MOV PC,SP ;INITIALIZE SP TO START
000502' 005746 TST -(SP)
;
177560 KBSTAT=177560
177562 KBDATA=177562
177564 PRSTAT=177564
177566 PRDATA=177566
;
000504' 012746 000015 MOV #15,-(SP) ;CR CODE TO STACK
000510' 012746 000012 MOV #12,-(SP) ;LF CODE TO STACK
000514' 105767 177560 LOOP: TSTB KBSTAT ;CHARACTER ENTERED?
000520' 100375 BPL LOOP ;NO KEEP IDLING
000522' 016700 177562 MOV KBDATA,R0 ;(R0)=CHARACTER
000526' 042700 177600 BIC #177600,R0 ;CLEAR ALL BUT CODE BITS
000532' 020027 000015 CMP R0,#15 ;IS CHARACTER CR?
000536' 001402 BEQ OUT ;IF SO, GO TO OUTPUT
000540' 010046 MOV R0,-(SP) ;ELSE PUSH CHARACTER ON STACK
000542' 000764 BR LOOP ;AND RETURN FOR NEXT CHARACTER
000544' 105767 177564 OUT: TSTB PRSTAT ;IS PRINTER READY
000550' 100375 BPL OUT ;IF NOT, KEEP IDLING
000552' 012667 177566 MOV (SP)+,PRDATA ;IF SO, POP NEXT CHARACTER AND PRINT IT
000556' 020627 000500' CMP SP,#START ;IS STACK EMPTY?
000562' 001746 BEQ START ;IF SO, ACCEPT NEW LINE
000564' 000767 BR OUT ;IF NOT, GO ON PRINTING
.END START
Returned from secondpass()

No errors detected

Assembly statistics (words):

Absolute Relocatable
Code 0 187
Reloc. info 0 1

Space used for symbol table: 780 words
Total workspace used: 993 words
Assembly complete
0.000>

I wish the copy would 'copy' the contents like it is on the screen..
Anyway I would Enter a line of Text, followed by a Carriage Return and using the Stack it will Print the line BackWards..
This will test some features of my PDP 11/45 that I have Not Tested before..

THANK YOU Marty
 
Hi All;
I have had to play with my M7800 a little bit.. I tried Dave's Modification.. Only, I first used a pair of resistors, that He figured out for me Off-post..
They didn't work, but it gave me a starting point.. They were 2K to the -12 volts and 1.43 (1.5)K to ground.. So, I took a 5K Pot and used it instead..
Somewhere in the Range of -2.25 to 1.50 volts, seems to work.. Higher than about 2.50 volt and it doesn't work, and I have not yet tried lower than 1.5 volts.. It is working better.. But, still not all of the time for my USB to Serial converter.. I will Play with it some more and hopefully get a Voltage that works, and let Everyone Know..
So, far -1.20 volts and 4800 Baud, work the best, still not perfect, but better..
If, anyone else is trying this, Please let Us know what Voltages and Resistor Values You find that work.. The Orange in the picture is the Camera..

001.jpg

THANK YOU Marty
 
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Hi All;
I found out, after Taking out the Resistor divider (pot), that I may not have had to do so.. I did not get any input from the other computer with the com port, as so I thought it wasn't working with the resistor divider.. So, I changed it back to the origional Capacitor..
Come to find out, I had forgot to plug in the Keyboard to that computer and one of the wires had come off of it pin, So there was two reasons "why" the input didn't work.. I have it working now..
The resistor divider has 57 ohms to ground and 4.64K to -12 volts, these can be changed some.. But this should give You a ball Park figure of where to start..
So, far I am not able to Load, my Backward.ptap file, to the PDP 11/45 using the Regular Loader.. So, I will need to find another way to make a Loadable file, as I am toooo lazy to put it in with the switches, even though I just might do that sometime later this coming week..
But, I still need to figure out what the output file need to have in it to make it Loadable, after having Loaded the ABS.bin file from "TT" and then loading what files I want to test this machine with.. Since all I have at present is mostly Memory Test Programs..
I did Run one of the Extensive Memory Test Programs, and it Passed.. I will sometime this week, try this 32K (28K) with the Memory Management Boards, and see IF I can still get the the I/O ports to show up in their Proper place.. Which they did not do before, but that was with a 128K memory Board.. Maybe I need to figure out, "How" to turn off the top 4K, before it will work correctly.. Which by using a 32K board, this should be no problem, if the Memory Management is working correctly..

THANK YOU Marty
 
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Hi All;
I have put in the M8107 and M8108 Memory Management Boards, with the same 32K memory, that I had in the machine..
And it Will Not Show the ODT type of output, that I had before..
I have tried it at, 165020, which worked without the Memory Management Boards, and at 765020.. Both of which give me an Address Error Led Indication.. What I am going to do is Trace out the Signal pins that the SBJ Board uses and compare them and see if I can find any Address IC problems on the M8107, show up..

THANK YOU Marty
 
Hi All;
I went down some Rabbit holes, (no Rabbits found) trying to check things out.. I still have the 8881's to check out.. I found my Sockets to plug in one board, and then I can apply power (+5 volts), and while it's lying on the table, outside of the PDP 11/45, I can check out the various Ic's, via a pulser and my scope.. I could even attach it to many switches, and Lots of Led's, whereby testing it further out of the PDP 11/45..
On another note, I partially Sysgened Rsx11m, I think I answered something wrong, so I will try it again, in SimH..
Tomorrow I think I will have other work.. So maybe Wednesday..

002.jpg

THANK YOU Marty
 
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Hi All;

Here are a couple of Pictures, for the Wire-Wrap Board to Test the M8107 Board.. I will be only at first, doing only the Signals that I need.. Then Later, doing what else, is needed for the M8108 Board.. And then, possibly, adding what I would use on other Boards, until I have a completely Universal Test Board for the Hex style DEC Boards..
The Led's are working, at least what I need for the present.. Picture 4 is with the Regular Addresses wired in, next is the Virtual Addresses..

001.jpg 003.jpg 004.jpg

005.jpg 006.jpg

THANK YOU Marty
 
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Hi All;
I got all three rows of Led's wired up.. Some of them are not connected to anything, But when nothing is connected, then because of Inputs that are High, when nothing is attached the Leds light up..

001.jpg

THANK YOU Marty
 
Hi All;
Two things, One is I might not be getting anything done on the Wire-wrap board for today, as there are other things that need to get done..
And, Second, A few postings back I asked about Converting Rsx11m from either a Tsx (I think I have the ending correct) or a Dsk file to a straight .bin file, to be able to Serially Load it into my PDP 11/45..
Another way Of trying to do what I would like to do.. Would be to take the SerialDisk that is for the PDP 8 and Convert it to PDP 11 code/system/machine.. That would be wholly satisfactory to me, at least for now.. And, Yes, I have downLoaded the files for SerialDisk..
First, I would need to figure out what files are used/needed for the Windows/Linux side, and which were used on the PDP 8 side..

THANK YOU Marty
 
Marty said:
Hi All;
Two things, One is I might not be getting anything done on the Wire-wrap board for today, as there are other things that need to get done..
And, Second, A few postings back I asked about Converting Rsx11m from either a Tsx (I think I have the ending correct) or a Dsk file to a straight .bin file, to be able to Serially Load it into my PDP 11/45..
Click to expand...

Marty, A .bin file can only be generated of a memory resident program image, not something like a .dsk image file. If RSX11M were a single memory resident program it could be done. But RSX11M is a collection of programs, not just one, on a file-structured disk media. A .bin is not possible.

Another way Of trying to do what I would like to do.. Would be to take the SerialDisk that is for the PDP 8 and Convert it to PDP 11 code/system/machine.. That would be wholly satisfactory to me, at least for now.. And, Yes, I have downLoaded the files for SerialDisk..
First, I would need to figure out what files are used/needed for the Windows/Linux side, and which were used on the PDP 8 side..

THANK YOU Marty
Click to expand...
SerialDisk for PDP-11 is what TU58EM already is ... so you would basically be reinventing the wheel.

DD.SYS drivers already exist for XXDP and RT-11. Not sure about RSX11-M, I have never been a user/fan of that OS.

If it were (easily) possible to write a DD driver for OS8 (the protocol is on the more complex side) then TU58EM plus a serial card in the PDP-8 plus an OS8 'DD.SYS' driver would have done the same thing as SerialDisk does. The problem is that it is not likely that an OS8 TU58 device driver can fit in the 1 or 2 page size requirement for drivers (ie, 128 or 256 12b words). Probably why DEC (or anybody else) never did it.

Don
 
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Hi All;
Thank You Don, for setting me straight..
So, for Now my best route would be to try and get another M7800 Or M7856 going..
Actually, I wouldn't care if I had RT11 or RSX11M going, as long as I could have something.. Even Unix Ver 1, which is All in Assembly Code for a PDP 11 (I think).. I will need to look at it closer..
I have some Old Unix Manuals, I will need to see which version they are for..
They are for BSD 4.2.. "4.2 Berkeley Software Distribution Virtual Vax-11 Version" April-August 1983.. And NO I don't have the Tapes/Files.. Just the Manuals, I Probably got them from CU here in Boulder at some Time, long time ago..
Which would help me shake down my 11/45..

THANK YOU Marty
 
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Hi All;
I have found and corrected A problem, on the M8107 Memory Management board.. I can't say that this will fix it, but it can't Hurt..
E41, an 8881 (7439), when any one of its inputs was Pulsed by my Pulser, then All Four Outputs would follow Inversely..
Now that I have it fixed, it no longer displays this problem..
This affected bits 16, 13, 12 and 9..
I am going to put Both Boards in and see whether this helps.. M8107 and M8108..
It looks like that fixed it, I won't be able to tell, till I get my other Computer mounted on top of the 11/45 and can then use Tera-Term on Com Port 2, and see whether I get an Output..

THANK YOU Marty
 
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Hi All;
I have it Partially Working.. At this point I am not sure whether it it my Serial Board, or my Memory Management Board(s)..
But, I can easily narrow it down, I can put back in my SJB Board, and If my Serial Board works..
Then I know its the Memory Management Board(s).. If not then it the Serial Board..
I can at present copy a switch setting back to the Led's, using the address 777570.. And I can see the Input from 777560 and 777562, but no output from 777566.. I will check the First three Bits on the M8107 Board..
It does the same thing with the SJB Board.. Most likely at this point its the Serial Card.. But, not necessarily, as what feeds the Serial Card and the SJB Board and the Memory Management Board, might be where the problem is, possibly the Data Paths Board or the PDR Board.. I will need to follow the signal back from the Serial Card, If the Serial Card is not the problem..

THANK YOU Marty
 
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Hi All;

I Just Killed the 11/45 !!!! The Last two Boards that I put in, I had Mis-looked and so, I was off by one slot..
Back to Square One, Maybe even Zero.. It looks Like I will Definitely need/have to finish my Quad Board Tester, Now..

THANK YOU Marty
 
Hi all;
Thank You, Jack.. May the Coming New Year, bring You much Happiness, and May all of Your Systems come up with very Little trouble..
I have for Now, put the PDP 11/45 away.. And I have put the PDP 11/40 on the Kitchen table.. I hope to put it to use to help me fix the 11/45 Boards.. If Nothing else, I needed a more sturdy Mounting structure for the Boards that I will be trying to test which came from the 11/45.. The wires on the Left are from a previous project.. So for Now I will leave them..

001.jpg


THANK YOU Marty
 
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Hi All;
Thank You, M-Thompson for Your Kind and Thoughtful comments..
I would have thought that my posting would have been "on How Not to proceed"..
Would You happen to have an 11/40 as well..
I will be getting Back to the PDP 11/45, I have to just give it some time..
But, I can't stop thinking about it and so working on it.. So, Hopefully it won't be tooooo long..

THANK YOU Marty
 
Hi All;
M-Thompson. As far as I am concerned, same thing.. Yours uses the same Boards as mine..
Does Yours Run, at all, minimally, not at all ??
What Rev is Your U Word Rom Board ??

THANK YOU Marty
 
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