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Build your own PDP 8I, Part 2..

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  • Marty
    replied
    Hi All;

    More differences between the lists..

    On the INT sorted List B19 (F12) (Page 80) pin 1 A37-4 (E4-4) is crossed from the List and B18-1 (F13-1) is left attached..
    On the EXT sorted List F12 (B19) (page 30) has attached to pin 1 E4-4 (A37-4) and F13-1 (B-18-1)..
    I have E4-4 floating..

    On INT sorted List B24 (F2) (Page 85) pin 2 has A50-2 (G3-2) and P1-77 attached to it, A50-2 has been crossed off and B31-4 (H12-4) written in its place..
    On EXT sorted List F2 (B24) (Page 20) pin 2 has G3-2 (A50-2) and P1-77 attached to it.. PC0

    On INT sorted List B24 (F2) (Page 85) pin 5 has A50-5 (G3-5) and P1-83 attached to it, A50-5 has been crossed off and B32-4 (H11-4) written in its place..
    On EXT sorted List F2 (B24) (Page 20) pin 5 has G3-2 (A50-5) and P1-83 attached to it.. PC1

    On INT sorted List B24 (F2) (Page 85) pin 7 has A50-10 (G3-10) and B33-4 attached to it, A50-10 has been crossed off and (P1-89) written in its place..
    On EXT sorted List F2 (B24) (Page 20) pin 7 has G3-10 (A50-10) and H10-4 attached to it.. PC2

    On INT sorted List B24 (F2) (Page 85) pin 10 has A50-13 (G3-13) and P1-95 attached to it, A50-13 has been crossed off and B34-4 (H9-4) written in its place..
    On EXT sorted List F2 (B24) (Page 20) pin 10 has G3-13 (A50-13) and P1-95 attached to it.. PC3

    On INT sorted List B24 (F2) (Page 85) pin 12 has A49-2 (G4-2) and P2-56 attached to it, A49-2 has been crossed off and B35-4 (H8-4) written in its place..
    On EXT sorted List F2 (B24) (Page 20) pin 12 has G4-2 (A49-2) and P2-56 attached to it.. PC4

    On INT sorted List B34 (H9) (Page 92) pin 4 has A50-13 (G3-13) crossed off and B24-10 (F2-10) written in..
    On the EXT sorted List H9 (B34) (page 59) pin 4 has G3-13 (A50-13) is listed..

    On INT sorted List B35 (H (Page 93) pin 4 has A49-2 (G4-2) crossed off and B24-12 (F2-12) written in..
    On the EXT sorted List H8 (B35) (page 5 pin 4 has G4-2 (A49-2) is listed..

    On INT sorted List B47 (L (Page 105) pin 3 has C2-1 (J5-1) and A45-6 (M10-6) A45-6 is crossed off and A10-1 (M16-1) is written in..
    On EXT sorted List L8 (B47) (page 93) pin 3 has J5-1 (C2-1) and M10.6 (A45-6) is listed..

    That is all of the Write in Differences, I have NOT checked the rest of the IC's (Gates) that have nothing written on them..
    I still need to do that..

    THANK YOU Marty
    Last edited by Marty; June 1, 2015, 07:44 PM.

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  • Marty
    replied
    Hi All;
    Thank You Kyle for the information and the small program, I will probably try it tomorrow, when I get the Machine back in front of me..
    At present, I am trying to get all of the Wire-Listing Differences up-loaded..
    Note -- That these are Wire List differences and NOT Schematic to wire List Differences..
    Schematic to wire List Differences is for another List..

    THANK YOU Marty

    Leave a comment:


  • Marty
    replied
    Hi All;

    More differences between the lists..

    On the INT sorted List A50 (G3) (page 49) pin 2 goes to B24-2 (F2-2) and B31-4 (H12-4) Both have been crossed out and attached to P1-78 (MB0)..
    On the EXT sorted List G3 (A50) (page 37) pin 2 goes to F2-2 (B24-2) and H12-4 (B31-4) (PC0)..

    On the INT sorted List A50 (G3) (page 49) pin 5 goes to B24-5 (F2-5) and B32-4 (H11-4) Both have been crossed out and attached to P1-84 (MB1)..
    On the EXT sorted List G3 (A50) (page 37) pin 5 goes to F2-5 (B24-5) and H12-4 (B32-4) (PC1)..

    On the INT sorted List A50 (G3) (page 49) pin 10 goes to B24-7 (F2-7) and (P1-89) Both have been crossed out and attached to P1-90 (MB2)..
    On the EXT sorted List G3 (A50) (page 37) pin 10 goes to F2-7 (B24-7) and (P1-89) (PC2)..

    On the INT sorted List A50 (G3) (page 49) pin 12 goes to B24-10 (F2-10) and B34-4 (H9-4) Both have been crossed out and attached to P1-46 (MB3)..
    On the EXT sorted List G3 (A50) (page 37) pin 12 goes to F2-10 (B24-10) and H9-4 (B34-4) (PC3)..
    On this and the following Signals involving PC00 thru PC04, I have tried it using MB00 thru MB04 and it doesn't WORK !! So, I have Left all of these attached to PC00 thru PC04..

    Thank You Marty
    Last edited by Marty; June 1, 2015, 06:21 PM.

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  • antiquekid3
    replied
    If single-stepping instruction 7430 (CLA CLL CML) causes the PC to be cleared, I'd say there are definitely issues. Do each of those instructions by themselves work? Do two instructions together work? That'd be where I'd begin debugging that.

    Try single-stepping:
    0000/ 7200 CLA
    0001/ 7100 CLL
    0002/ 7020 CML
    0003/ 7300 CLA CLL
    0004/ 7220 CLA CML
    0005/ 7120 CLL CML
    0006/ 7320 CLA CLL CML

    Maybe you can figure out from there what the issue might be.

    Leave a comment:


  • Marty
    replied
    Hi All;

    More differences between the lists..

    On the INT sorted List A33 (E11) (page 34) pin 13 goes to A8-3 (G9-3) and A21-1 (E15-1) is crossed off..
    On the EXT sorted List E11 (A33) (page 13) pin 13 goes to G9-3 (A8-3) and E15-1 (A21-1)..

    On the INT sorted List A36 (G16) (Page 37) pin 3 goes to A43-10 (K2-10) and is crossed off and A13-5 (M15-5) is written in..
    This is part of the Mod I referred to in the last posting.. A simplification of the circuit.. I have not implemented it..
    On the EXT sorted List G16 (A36) (page 50) goes to K2-10 (A43-10)..

    On the INT sorted List A37 (E4) (page 3 Pin 4 has it going to B19-1 (F12-1) which is crossed out and it is wired to A37-5..
    Signal A0 is eliminated.. I have the pin Floating..
    On the EXT sorted List E4 (A37) (Page 6) is going to F12-1 (B19-1)..

    On the INT sorted List A43 (K2) (page 42) pin 8 goes to A36-4 (G16-4) and it is crossed out..
    On the INT sorted List A43 (K2) (page 42) pin 9 goes to A11-2 (K4-2) and it is crossed out..
    On the INT sorted List A43 (K2) (page 42) pin 10 goes to A36-3 (G16-3) and it is crossed out..
    On the EXT sorted List K2 (A43) (page 72) pin 8 goes to G16-4 (A36-4)..
    On the EXT sorted List K2 (A43) (page 72) pin 9 goes to K4-2 (A11-2)..
    On the EXT sorted List K2 (A43) (page 72) pin 10 goes to G16-3 (A36-3)..
    This finishes the Mod referred to on last posting.. I have not implemented it..

    On the INT sorted List A45 (M10) (Page 44) pin 3 goes to A9-10 (M1-10) and A45-6 (M10-6) has been added..
    On the INT sorted List A45 (M10) (Page 44) pin 6 goes to B47-3 (L8-3) and A10-1 (M16-1) have both been crossed out and A45-3 has been added..
    A0 is eliminated and I have left M10-6 floating..
    On the EXT sorted List M10 (A45) (page 106) pin 3 goes to M1-10 (A9-10)..
    On the EXT sorted List M10 (A45) (page 106) pin 6 goes to L8-3 (B47-3) and M16-1 (A10-1)..

    On the INT sorted List A49 (G4) (page 4 pin 2 goes to B24-12 (F2-12) and B35-4 (H8-4) Both have been crossed out and attached to P2-55 (MB4)..
    On the EXT sorted List G4 (A49) (page 3 pin 2 goes to F2-12 (B24-12) and H8-4 (B35-4) (PC4)..
    On this and the following Signals involving PC00 thru PC04, I have tried it using MB00 thru MB04 and it doesn't WORK !! So, I have Left all of these attached to PC00 thru PC04..

    THANK YOU Marty
    Last edited by Marty; June 1, 2015, 05:07 PM.

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  • Marty
    replied
    Hi All;
    Kyle, Thank You for the reminder, Which was Why I wanted to try it starting at 0001.. I was kind of thinking the same thing..
    I will put it on the back Burner for awhile.. Maybe something will come to mind..

    PBirkel, here is the first of the many differences between the two lists, (There will be many edits)..
    Also, it may be Helpful to look at the Pages under Your copied PDF format for easier Viewing..

    On the INT sorted List A10 (M16) (page 11) Shows pin 1 of the 7430 originally going to A45-6 (M10-6) it is crossed out and is wired to B47-3 (L8-3).. It is also wire to A98-10 (K19-10)..
    Thereby eliminating Signal A0 from the equation.. When I first tried this, before finding the 'F' enable not working, the PDP 8i clone would not work with this signal missing.. I have not tried it since then, I will put it on my list to do..
    On the EXT sorted list M16 (A10) (page 112) shows pin 1 of the 7430 going to M10-6 (A45-6) and K19-10 (A98-10)..

    On the INT sorted List A11 (K4) (page 12) Shows pin 2 of the 7402 originally going to A12-9 (M12-9) and also to A43-9 (K2-9) which has been crossed out..
    Also on the same page A11 shows pin 4 going to A11-3 (K4-3) and also to A43-11 (K2-11) which is crossed out and P1-60 is written in..
    This Eliminates two of the Signals from G16, which when another mod is applied, will do the same thing only it will Simplify the circuit.. At this time I have Not applied this Change..
    On the EXT sorted List K4 (page 74) shows pin 2 wired to M12-9 (A12-9) and also K2-9 (A43-9)..

    On the INT sorted List A13 (M15) (page 14) pin 5 goes to A52-5 (K14-5) and has been written in (added) A36-3 (G16-3).. This is part of the above mentioned Mod..
    On the EXT sorted List M15 (A13) (page 111) pin 5 goes to K14-5 (A52-5)..

    On the INT sorted List A19 (E1) (page 20) pin 3 goes to C1-1 (J6-1) and has been written in (added) A21-1 (E15-1)..
    Signal has been changed from F1 to F0.. I have implemented this change and it agrees with the Equations..
    On the EXT sorted List E1 (A19) (page 3) goes to J6-1 (C1-1)..

    On the INT sorted List A21 (E15) (page 22) pin 1, A33-13 (E11-13) is taken off and it is wire to A19-3 (E1-3)..
    Signal has been changed from F1 to F0.. I have implemented this change and it agrees with the Equations..
    On the EXT sorted List E15 (A21) (page 17) is wired to E11-13 (A33-13)..

    More on the next posting..

    THANK YOU Marty
    Last edited by Marty; June 1, 2015, 03:33 PM.

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  • antiquekid3
    replied
    Marty, remember that locations 10-17 are autoincrement and will give very weird behavior if you reference them indirectly.

    Leave a comment:


  • Marty
    replied
    Hi All;

    I found a variation of something that seems to work with this program..

    Address 0000 Data 0000
    Address 0001 Data 7200
    Address 0002 Data 3000
    Address 0003 Data 2005
    Address 0004 Data 7402
    Address 0005 Data 5001

    It Starts at Address 0001.. I will run continuously and Not Halt.. I think this is correct..
    Next is Kyle's Program.. I will let You Know..

    I does Not run Kyle's program, but it is not what one would think as to why..

    Address 0000 Data 0000
    Address 0020 Data 7320
    Address 0021 Data 7010
    Address 0022 Data 2000
    Address 0023 Data 5022
    Address 0024 Data 7430
    Address 0025 Data 5027
    Address 0026 Data 5021
    Address 0027 Data 7004
    Address 0030 Data 2000
    Address 0031 Data 5030
    Address 0032 Data 7430
    Address 0033 Data 5021
    Address 0034 Data 5027
    Address 0035 Data 0000
    Address 0036 Data 0000
    Address 0037 Data 0000

    I start it 0020 and the next instruction, which should show it at 0021, instead is at 0000 !!!!! Go figure..
    I will put it into single step mode and see what shows up..
    I re-assembled Kyle's program to start at 0001 instead of at 0020, but not any better.. I need to take a closer look at things..

    THANK YOU Marty
    Last edited by Marty; June 1, 2015, 12:25 PM.

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  • Marty
    replied
    Hi All;

    I'm back.. I have tried a few variations, and I need to put them down on paper and make a list of what does what..
    PBirkel, I haven't forgotten about Your request..

    THANK YOU Marty

    Leave a comment:


  • Marty
    replied
    Hi All;

    It doesn't work right with the Mod, but it looks very promising, I have an errand to do and so I won't be back till sometime between 10:00 and 11:00.. Then I can single step thru the various steps and see what/where the problem lies..

    THANK YOU Marty

    Leave a comment:


  • Marty
    replied
    Hi All;
    PBirkel, No Problem.. I will List what I have of them Tomorrow, for You to Look at..
    I think, but I don't know for sure, But, I think one is an Earlier listing and the other is a Later Listing..

    THANK YOU Marty

    Leave a comment:


  • pbirkel@gmail.com
    replied
    Originally posted by Marty View Post
    Hi All;
    PBirkel, there ARE differences between the two lists, so far they are write in on the IntList versus the ExtList, but I have not had time to check everything between the two..
    THANK YOU Marty
    Not asking you to but ... could you provide a specific example(s)? I'd like to verify it/them for myself. These line printer listings are not-so-clear, and thus may be subject to misinterpretation. Would like to see if there's an objective discrepancy, please.

    Leave a comment:


  • Marty
    replied
    Hi All;
    PBirkel, there ARE differences between the two lists, so far they are write in on the IntList versus the ExtList, but I have not had time to check everything between the two..
    I will on Monday be checking to see if by eliminating one 7404 gate and changing one 7400 gate to a 7402 gate might make ISZ work..

    THANK YOU Marty

    Leave a comment:


  • pbirkel@gmail.com
    replied
    Originally posted by Marty View Post
    Hi All;
    Thank You, Pbirkel for posting these online for others to have access to, and sharing these files with Everyone..

    THANK YOU Marty
    Well, don't thank me. They come from someone close to one of the book authors. I've been slow to post them because there has been minimal interest in them from folks here :-<. Anyway ...

    My objective remains to move the wire-list(s) -- which I've been repeatedly assured *is* correct (one is simply the inverse of the other) -- to a PCB tool and eventually to fabricate a PCB as well as the exactly-corresponding schematic. Your difficulties using those wire-lists are quite worrying. I remain hopeful that when you have a working implementation your notes will be sufficient to identify where there may be errors in the source materials.

    Note that Oscar V., over on the N8VEM forum, has expressed interest in putting together a front panel-derivative from his PiDP-8 project. That would be quite nice, but there are lots of questions to be answered first ...

    Keep on wrapping ... (and, alas, unwrapping).

    Leave a comment:


  • antiquekid3
    replied
    Originally posted by Marty View Post
    Hi All;
    Thank You, Jack for Your suggestion.. "" After all, it's summer and you must have lots of free time. ""
    Not as much as You might think, there are alot of Trailer Issues, that have come up since the flood, that just now are showing up.. And need fixing and constant attention..
    I Looks like the ISZ Instructions is working, I am waiting for the test to finish, to also evaluate the SZA instruction as well..
    It partially has ION/IOFF working, but there needs to be some wiring changes in that section, as well as numerous other stuff before I/O would work at all.. There would need to be another Socket added for the I/O signals that would be put on the Memory Board, turning it into a Memory/I-O Board..
    Kyle, Thank You for the very Kind words and information on the BSW instruction..
    "" but I'm guessing you're still a few months out from having two working serial ports. ""
    It shows how to wire up One Port, but NOT two Ports, it does give some hints, but nothing more..
    But, at present, even One Port would be of a Great Help..
    Marty, I may be mistaken, but I think Jack was referring to my infinite amount of free time now that I'm off from school for the summer. Unfortunately, I've moved up to Baltimore for the summer and am working full time, which doesn't give me too much time for hobbies.

    Originally posted by jackrubin View Post
    Mmm - and maybe deal with ION/IOFF?? :>)
    After all, it's summer and you must have lots of free time.
    To add ION/IOFF support for SerialDisk? If so, does anyone really need support for that? I am having trouble thinking of a use case. During block transfers, the PDP-8 isn't doing anything but handling transfers, and with the speed of the computer SerialDisk is running on, it should never have any trouble keeping up, even at 230.4k baud, which, besides the Omni-USB board, is the fastest I've ever run SerialDisk at.

    A few things that are in the works are a parallel version utilizing a DR8-E connected to a microcontroller, as well as getting SerialDisk ported to the DECmate series. Still figuring out the darned serial port there. I'll start a thread of SerialDisk discussion separately, though.

    Michael, I will try to look into replacing BSW with a few RTR/RTL/RAR/RALs and such. I think I have enough room to do that now, even in the cramped system handler. Another thing in the works is modifying the non-system handler to support four RK05 images, versus the current two. That'll also require a few minor mods to the server, but again, those are quite minor and involve some copy-paste-modify.

    Kyle

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