SIMUL: PDP-11 Simulator

Original SIMUL

SIMUL emulates a PDP-11 without MMU and it runs CPU tests loaded from a paper tape. SIMUL used to have a very cool built-in debugger which appears lost.

The code of SIMUL contains Russian comments in KOI-8. Set your browser appropriately.

SIMUL is written in PL/M language. The idea of PL/M comes from Hungarian system IDOS for Mitra-15. It was reengineered anew by Vladimir Butenko, to become a part of his PhD thesis later (in 1990 or so.)

First version of SIMUL was written by Ivan Bobrov, but it was not finished. I made it work more or less. Late Mikhail Flerov contributed suggestions that made SIMUL no less than 3 times faster.

coiini.plm
cooini.plm
devini.plm
errors_11.txt	TODO list
floppy.plm	8 inch floppy disk.
it.plm
ldaddr.plm
pdp_11.plm	The main loop. It also has a call to the missing debugger...
read.plm	This section was written by Mikhail Flerov. SIMUL ran in 64K total (code + data) and emulated a machine with 56K of memory. READ implements a necessary virtualization.
regini.plm
start.plm
step.plm
stlini.plm