prsim: Production rule simulation

Before using prsim to simulate a set of production rules, they must first be flattened using aflat. Assuming your production rules are in a file called circuit.act, you would run:

aflat circuit.act > circuit.prs
prsim circuit.prs

This will give you an interactive (Prsim) prompt. Type help to get a list of simulation commands.

When running prsim, it is good practice to use a test .act file that looks something like this:

import "circuit.act";
...
... // your test setup

bool Reset;

prs {
   Reset -> Vdd+
   Reset -> GND-
   Reset => _Reset-
}

In this example, I've assumed that the circuit reset signals are the global variables Reset and _Reset. You should use the appropriate signals for your circuit there. The nice thing about this setup is that you can have a prsim script file that looks something like this:

random
set Reset 1
cycle
status U
... // watch various things
set Reset 0
cycle

help

display a list of commands with short descriptions

exit

terminate

source <file>

read in a script file and execute the commands within

array <variable> <range> <command>

execute multiple of one command. Variable is a string that is replaced with the current iteration. Since it is just blind string replacement, you'll probably want to name it something like $i to prevent conflicts within the repeated command. Range should be of the format start:end[:step] (the brackets mean step is optional).

save <file>

save a simulation checkpoint to the specified file

restore <file>

restore simulation from a checkpoint

random [<min> <max>]

Set the random timing mode and optionally specify the default random timing bounds for all nodes.

random_seed <seed>

set the seed for the random timing mode.

norandom

Set the deterministic timing mode.

random_excl on|off

turn on/off random exclhi/lo firings

after <n> <minu> <maxu> <mind> <maxd>

For the random timing mode, set the random timing bounds for the up and down transitions for a specified node.

mode reset|run|unstab|nounstab

set current running mode.

initialize

initialize the simulation, setting all nodes to X.

step [<steps>]

simulate <steps> transitions (default is 1)

advance [<duration>]

simulate for <duration> units of simulation time (default is 1)

cycle [<node>]

simulate until the next transition on <node> (default is forever)

break <node>

set a breakpoint on <node>

break-on-warn

toggles the break-on-warn flag which stops/doesn't stop simulation on instability or interference

exit-on-warn

like break-on-warn, but exits prsim

set <variable> <value>

set the node, bus, or vector <variable> to specified <value>

get <variable>

get value of a node, bus, or vector <variable>

assert <variable> <value>

assert that the node, bus, or vector <variable> is <value>

seu <node> 0|1|X <start-delay> <dur>

Delayed SEU event on node lasting for <dur> units

uget <n>

get value of node <n> but report its canonical name

watch <n>

add watchpoint for <n>

unwatch <n>

delete watchpoint for <n>

watchall

watch all nodes