assign_local_clock (Fusion and ProASIC3/E)

Assigns regular nets to LocalClock regions.

assign_local_clock -net netname -type clock_type clock_region

Arguments

-net netname

Specifies the name of the net to assign to a LocalClock region.

-type clock_type

Specifies the type of region to which the net will be assigned:

clock_region

Specifies a LocalClock region.

LocalClock regions are defined as one of the following:

• A single spine defined as T# (Top spine) or B# (Bottom spine)

• A multi-spine rectangle defined as [T | B]#:[T | B]#

Spines are numbered from left to right starting at 1. The maximum spine number is a function of the die selected by the user. Please refer to the examples in this help topic.

Local clock uses clock spine resources remaining after global assignment from Input Netlist and PDC constraints. There are six chip-wide and twelve quadrant-wide clock resources per device. You may reserve portions of a clock network (chip-wide or quadrant-wide) for local clocks by assigning clock nets to regions. If there are not enough clock resources to honor all local clock assignments, the Layout command will fail.

Supported Families

Fusion and ProASIC3/E

Note: You must import the PDC file along with the netlist as a source file because Compile needs to delete buffers and legalize the netlist.  Shared instances between local clocks are supported. Compile will insert buffers to legalize the netlist.

Exceptions

• If the net is a clock net, it is demoted to a regular net. You will see an unassign_global_net command in the PDC file if the net is demoted to a regular net by the compiler and the assignment to local clock failed.

Examples

This example assigns the net named localReset to the chip-wide spine T1:

assign_local_clock -net localReset -type chip T1

This example assigns the net named localReset to the quadrant spines T1, T2, T3, T4, and T5, which span more than one quadrant:

assign_local_clock -net localReset -type quadrant T1:T5

This example assigns the net named localReset to the chip-wide spines T1, T2, T3, T4, T5, T6, B1, B2, B3, B4, B4, and B6:

assign_local_clock -net localReset -type chip T1:B6

See Also

Assign net to local clock

unassign_local_clock

assign_quadrant_clock

PDC syntax conventions

PDC naming conventions