blockPre

Breaks algebraic loops by an infinitesimal small time delay (y = pre(u): event iteration continues until u = pre(u))

Extends from Blocks.Interfaces.partialBooleanSISO (Partial block with 1 input and 1 output Boolean signal).

Information

This block delays the Boolean input by an infinitesimal small time delay and therefore breaks algebraic loops. In a network of logical blocks, in every "closed connection loop" at least one logical block must have a delay, since algebraic systems of Boolean equations are not solvable.

The "Pre" block returns the value of the "input" signal from the last "event iteration". The "event iteration" stops, once both values are identical (u = pre(u)).

Parameters

TypeNameDefaultDescription
Booleanpre_u_startfalseStart value of pre(u) at initial time

Connectors

TypeNameDefaultDescription
Blocks.Interfaces.BooleanInputu (from partialBooleanSISO)Connector of Boolean input signal
Blocks.Interfaces.BooleanOutputy (from partialBooleanSISO)Connector of Boolean output signal