These changes facilitate more robust parameter type checking and helps
to identify unexpected coding errors.
Most simulators can now also be compiled with a C++ compiler without
warnings.
Additionally, these changes have also been configured to facilitate easier
backporting of simulator and device simulation modules to run under the
simh v3.9+ SCP framework.
This allows simulator code to be insulated from any changes which may
be made to the REG structure in the future. The REGDATA macro will be
update as needed to avoid any changes in simulator specific code.
Update description of DEVICE, UNIT, and REG. Correct a number of
typos and formatting glitches. Add description of UNIT_IDLE,
REG_UNIT. Add some missing details in fprint_sym and
sim_vm_is_subroutine_call. Document command matching rule.
Altered the calling sequences to fprint_sym and parse_sym in ex_reg and dep_reg to merge user-defined register flags with the radix in the addr parameter. This allows the print and parse routines to identify the register or determine how it is to be handled. These are called in lieu of the standard print and parse routines if a register has REG_VMIO or at least one user-defined flag set.
simh.doc Writing a Simulator for the SIMH System
sim_breakpoints.doc The SIMH Breakpoint Subsystem
sim_vmio.doc Adding An I/O Device To A SIMH Virtual Machine
