fsml

A library for describing and describing synchronous finite state machines
IN THIS PACKAGE
Module Fsml . Simul

Simulation

type ctx = {
state : State.t;
env : Expr.env;
}

A context is the dynamic view of a FSM. It records its current state and, in env, the value of its inputs, outputs and local variables.

Simulation functions

val step : ctx -> Fsm.t -> Event.t list * ctx

step ctx m performs a single simulation step, within context ctx of FSM m. The first fireable transition is selected according to the current state and value of the inputs and local variables. The actions associated to this transition are executed and both the state and context are updated accordingly. If no fireable transition is found, the context is left unchanged. Returns a list timed output events and the updated context.

val run : ?ctx:ctx -> ?stop_when:Guard.t list -> ?stop_after:Clock.clk -> ?trace:bool -> stim:Tevents.t list -> Fsm.t -> Tevents.t list * ctx Clock.clocked list

run ctx stim m performs a multi-step simulation of FSM m starting from context ctx and applying a ordered sequence of stimuli listed in stim, producing a sequence of timed event sets and, if the optional argument trace is set, the corresponding sequence of contexts. FSM m is first type-checked. If the initial context ctx is not given it is built by triggering the initial transition of m and gathers its inputs, local variables and outputs. Passing an initial context may be used to start a simulation from a given state obtained from a previous simulation. If a list of guards is given as optional argument stop_when, then simulation stops as soon all of these guards of the these guards becomes true. The guards may include relational operators on the special variable clk, refering to the current simulation step. Ex: -stop_when [%fsm_guard {|rdy=1|}]; If a clock cycle count n is given as optional argument stop_after, then simulation stops after exactly n steps (so that -stop_after n is actually a shorthand for -stop_when "clk=n").