• Please review our updated Terms and Rules here

Search results

  1. J

    PDP-11 Diode ROM

    Megacool ... I feel like a copycat now! What secrets may be hidden in this huge box?
  2. J

    PDP-11 Diode ROM

    It's only a prototype, no PCBs left. Not sure where to go now ... is there public interest in a DIY kit?
  3. J

    PDP-11 Diode ROM

    FYI, here the schematics:
  4. J

    PDP-11 Diode ROM

    On the BM792, DEC used the 74138 instead of '154. Perhaps its easier to make a PCB layout with the smaller '138s?
  5. J

    PDP-11 Diode ROM

    Guys, Starting 2024 fun! Something new&nerdy here: https://www.retrocmp.com/projects/diode-rom-book A video showing operation will follow. kind regards, Joerg
  6. J

    TK50 emulator

    Josh Dersch made the QUniBone MSCP driver ... eternal thanks again! He planned for an TMSCP too ... but this seems to be more difficult, badly documented and not of such importance.
  7. J

    QProbe 2023

    QProbe2023 drives BRPLY, BHALT, BDCOK and BEVENT, but generation of 60Hz on LTC would need a small CPLD code change. Joerg
  8. J

    QProbe 2023

    Meant: "Joomla 3.x to 5.x"
  9. J

    QProbe 2023

    My flipchipshop.com died while migrating from Joomla 5.x to 5.x ... bit rot (hate this) So its still informal email, as usual. Joerg
  10. J

    QProbe 2023

    Guys, finally, finally I'm able to deliver enough QProbe2023s. Maybe I lost some preorders, please contact me again, if necessary. There's also a new web page describing wiring for the "Drive Activity LEDs" option on the Drive Bay Panel, see...
  11. J

    Is anybody still working with tapes at a PDP/11?

    Rüdiger ... You're the only man on this planet who has the PDP11GU beta with tape support ... Jörg
  12. J

    QProbe 2023

    You need to solder a 2x5 IDC connector to the prototyping area. and connect it with 5 wires to GND and existing LEDs. See J10 in the schematic.
  13. J

    QProbe 2023

    Guys, FYI: as Mark told, the new drive LEDs can be driven by both the BA23 panel connector and QBone simultaneously. The BA23 20pin panel cable is routed throught the QProbe LED panel. So if you like, you can wire up a BA23-QBone-QProbe combo. And as Mark is happy now, I declare the endless...
  14. J

    Use of Display Register at 777570, where?

    Hi, the UNIBUS DISPLAY register at 777570 give access to user LEDs on the old front panels. There seems to be not much talk about it. Is there any documented use by DEC itself, any OS, or is it just user playground? And was it ever implemented on any QBUS machine, even as an invisible dummy...
  15. J

    QProbe 2023

    "Sideways" is a topic. I've no idea for a "portrait" blinkenlight layout, never seen one for any other computer. And you want at least the 16 DATA LEDs in a single row, for these idle patterns => only "landscape" makes sense. Hmmm.
  16. J

    QProbe 2023

    The cables sit between the driving CPLD and the LEDs. They have no influence on QBUS impedance, can be a mile long.
  17. J

    QProbe 2023

    Here you are. Need to zip, ".STL" not allowed.
  18. J

    QProbe 2023

    Hi, here the 3D print to mount into BA23 case drive bay:
  19. J

    UNIBUS/QBUS alternative driver chips

    Hi, I had to find alternatives for the DS8641 bus driver chips ... seems they are all gone now. Choice for QBone is now AM26S10. Some thoughts have gone to http://www.retrocmp.com/projects/qbone/326-qbone-unibone-alternative-bus-drivers which can be enhanced. Any thoughts on that matter ...
  20. J

    PDP-11/20 runs UNIX V1 with UniBone devices

    Hi, FYI: Josh Dersch has written new UniBone emulationen for RS11/RF11 DECdisk and the KE11 EAE (11/20 arithmetic). Now he's able to run UNIX v1 on his bare 11/20 box. Thats's thrilling ... we're currently test 11/05 and good old '34 as other platforms. Thanks for this work! Joerg Unix V1...
Back
Top