Altera Quartus II Scripting - Manual (Page 617)

Chapter 3: Tcl Packages & Commands 3–487
timing_assignment
© July 2013 Altera Corporation Quartus II Scripting Reference Manual
create_relative_clock
Usage
create_relative_clock -base_clock <Base clock> [-comment <comment>] [-disable] [-divide
<integer>] [-duty_cycle <integer>] [-entity <entity>] [-invert] [-multiply <integer>]
[-no_target] [-offset <offset>] [-phase_shift <integer>] [-tag <data>] [-target <name>]
[-virtual] <clock_name>
Options
-base_clock <Base clock>: Base clock name
-comment <comment>: Comment
-disable: Option to disable assignment
-divide <integer>: Base clock division factor
-duty_cycle <integer>: Duty cycle
-entity <entity>: Entity to which to add clock assignment
-invert: Option to invert base clock
-multiply <integer>: Base clock multiplication factor
-no_target: Option to not assign clock to node
-offset <offset>: Offset from base clock
-phase_shift <integer>: Phase shift from base clock
-tag <data>: Option to tag data to this assignment
-target <name>: Clock node name
-virtual: Option to specify the clock as a virtual clock
<clock_name>: Clock name
Description
Creates a relative clock that derived from the absolute clock.
The "-offset" option can take the format:
<floating point time value><time unit>
For example, if the offset is 10.55ns, "10.55" is the <floating point time value> and "ns" is the <time unit>.
The following table displays possible time units:
Time Unit Description
s second(s)
ms millisecond(s)
us microsecond(s)
ns nanosecond(s)
ps picosecond(s)
fs femtosecond(s)