+# Overview #
+
+The `211bsd_simh` directory contains a working 2.11BSD disk image that can be
+booted using the included SIMH config file. Simply execute `simh system.conf`
+from within the `211bsd_simh` directory. Don't forget to `gunzip` the disk
+image file before use.
+
+If you need help installing/configuring SIMH, see my notes on installing SIMH
+located at
+<https://subgeniuskitty.com/development/pdp11/software_development/modern_unix>.
+
+If your console looks like the contents of the files in `7bit-encoding`, make
+sure the line `set tto 7b` is not commented out in `211bsd_simh/system.conf`.
+
+The files in `211bsd_install_tape` are a BSD install tape image and a PDF
+describing how to use it.
+
+
+# Status #
+
+Tested and working. This image runs regularly in SIMH and a real PDP-11.
+
+
+# Instructions #
+
+Clone the repository and un-gzip the disk image.
+
+ git clone git://git.subgeniuskitty.com/pdp11-211bsd-simh
+ cd pdp11-211bsd-simh/211bsd_simh
+ gunzip disk0_ra90_211bsd.dsk.gz
+
+From within the same directory, execute `pdp11 system.conf` to begin the
+simulation using SIMH.
+
+ PDP-11 simulator V3.9-0
+ Disabling CR
+ Disabling RK
+ Disabling HK
+ Disabling TM
+
+ 73Boot from ra(0,0,0) at 0172150
+ :
+
+This bootloader was loaded from block `0` of the first MSCP compatible disc
+device, which, per `system.conf`, is the file `disk0_ra90_211bsd.dsk`. This
+bootloader is sophisticated enough to load the UNIX kernel, but we have to tell
+it what device and file to load. Type `ra(0,0,0)unix` and press Enter to
+proceed.
+
+ : ra(0,0,0)unix
+ Boot: bootdev=02400 bootcsr=0172150
+
+ 2.11 BSD UNIX #1: Sat Aug 11 20:38:20 PDT 2018
+ root@curly.2bsd.com:/usr/src/sys/KRYTEN-NONET
+
+ ra0: Ver 3 mod 3
+ ra0: RA90 size=2376153
+
+ phys mem = 4186112
+ avail mem = 3990464
+ user mem = 307200
+
+ August 12 00:01:47 init: configure system
+
+ ra 0 csr 172150 vector 154 vectorset attached
+ cn 1 csr 176500 vector 300 skipped: No CSR.
+ cn 2 csr 176510 vector 310 skipped: No CSR.
+ cn 3 csr 176520 vector 320 skipped: No CSR.
+ cn 4 csr 176530 vector 330 skipped: No CSR.
+ erase, kill ^U, intr ^C
+ #
+
+The computer has now booted up to single-user mode and you are logged in as
+root. Unless you need to perform an operation in single-user mode, press
+`Ctrl-D` here to logout and let startup continue.
+
+ # Fast boot ... skipping disk checks
+ checking quotas: done.
+ Assuming non-networking system ...
+ checking for core dump...
+ preserving editor files
+ clearing /tmp
+ standard daemons: update cron accounting.
+ starting lpd
+ starting local daemons: sendmail.
+ Sun Aug 12 00:01:53 PDT 2018
+
+
+ 2.11 BSD UNIX (curly.2bsd.com) (console)
+
+ login:
+
+2.11BSD is now booted into multi-user mode. Login with username `root` and
+password `temppass` to get started.
+
+To shut down, as `root`, type `sync; sync; halt` to flush any buffers and halt
+the PDP-11 simulation. Then, type `quit` at the `sim>` prompt to exit SIMH.
+
+ login: root
+ Password:
+ erase, kill ^U, intr ^C
+ # sync; sync; halt
+ syncing disks... done
+ halting
+
+ HALT instruction, PC: 000014 (MOV #1,10544)
+ sim> quit
+ Goodbye
+
+Note that you can always halt the simulation and return control to SIMH by
+pressing `Ctrl-e` at any time. This drops to the `sim>` prompt. Entering `go`
+will resume simulation where it paused.