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Setup simh

  • Download simh and build it:

    mkdir simh cd simh unzip ~/Downloads/ make

  • Download a RT-11 disk image, such as RT11 v4 tar zxvf ~/Downloads/rt11swre.tar.Z

  • Other distributions:

  • Run the PDP-11 simulator, attach the disk image and boot the system:

    ~/simh$ ./BIN/pdp11
    PDP-11 simulator V3.9-0
    sim> attach rk0 ./Disks/rtv4_rk.dsk
    sim> boot rk
    RT-11SJ  V04.00C
    .D 56=5015
    Welcome to RT-11 Version 4. RT-11 V04 provides new hardware support
    and some major enhancements over Version 3B.
    Please use the HELP command;  it describes the new options in many
    of the utilities.
    If you are using a terminal that requires fill characters,
    modify location 56 with a Deposit command before proceeding with
    system installation. LA36 DECwriter II and VT52 DECscope terminals
    do NOT require such modification.
    .D 56=0

Changing directory

There are no directories in RT-11, although there are devices. To change the default device, reassign the device name DK: to another physical device:

      ASSIGN RK1: DK:

Installing software

  • Building FORTRAN IV and ADVENT are covered in ADVENT
  • Use PC: device to copy files in using the paper tape reader (ptr) and out with the paper tape punch (ptp):
         sim> <span style="color:red">attach ptr /tmp/input.txt</span>
         sim> <span style="color:red">c</span>
         .COPY PC: INPUT.TXT
          Files copied:
         PC:            to DK:INPUT.TXT
         sim> <span style="color:red">attach ptp /tmp/output.txt</span>
         sim> <span style="color:red">c</span>
          Files copied:
         DK:OUTPUT.TXT  to PC:

Unix on the PDP-11/34

According to this forum post, the PDP-11/34 did not have separate I&D and could not run normal Unix v7, only Digital's special v7m. However, these instructions seem to work on the simulated /34, including the boot loader code to read from the tape. Perhaps the RK05 image can be transferred to a real RK05 and booted.

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Last update: November 8, 2020