User manual

VAX MP SIMH console extensions

VAX MP SIMH console command set changes and extensions

VAX MP introduces a number of extensions and changes to SIMH console command set.

CPU MULTIPROCESSOR

Command CPU MULTI{PROCESSOR} <n> creates virtual processors in SIMH. For example the

following console commands create 6 virtual processors on the system, i.e. extra five CPUs in

addition to the primary CPU #0, and start the primary processor:

sim> CPU MULTI 6

sim-cpu0> BOOT CPU

CPU ID

Command CPU ID <n> sets default context for execution of other console commands. Console

user can switch between processor instances while examining and modifying their state:

sim-cpu0> EXAMINE PSL

[cpu0] PSL: 041F0000

sim-cpu0> CPU ID 2

sim-cpu2> EXAMINE PSL

[cpu2] PSL: 03C00009

Thus, for example, commands

CPU ID 2

EXAMINE STATE

DEPOSIT PSL 041F0004

STEP

will display the state of CPU2, change PSL of CPU2 and execute single instruction on CPU 2.

Explicit CPU unit specification in a command, such as for example

EXAMINE CPU3 STATE

overrides default context.

Reference to device “CPU” without specifying explicitly its unit number means a reference to

currently selected CPU, for example

CPU ID 2

EXAMINE CPU STATE

means a reference to the state of CPU2, not CPU0.

Device and register names do not depend on selected CPU and are the same for all CPUs.

Command SHOW DEVICES will list the same device names set for every CPU, regardless of

currently selected CPU context. However depending on the context, name can refer to different

device or register instances.