User guide

14-11
Negative Timing Checks
The $recrem Timing Check Syntax
The $recrem timing check syntax is very similar to the extended
syntax for $setuphold:
$recrem(reference_event, data_event, recovery_limit,
removal_limit, notifier, [timestamp_cond, timecheck_cond,
delayed_reference_signal, delayed_data_signal]);
reference_event
Typically the reference event is the active edge on a control signal,
such as a clear signal. Specify the active edge with the posedge
or negedge keyword.
data_event
Typically the data event occurs on a clock signal. Specify the
active edge on this signal with the posedge or negedge keyword.
recovery_limit
Specifies how much time must elapse after a control signal, like
a clear signal, toggles from its active state (the reference event),
before there is an active clock edge (the data event).
removal_limit
Specifies how much time must elapse after an active clock edge
(the data event), before the control signal can toggle from its active
state (the reference event).
notifier
A register whose value VCS toggles when there is a timing
violation.