reset_switching_activity - 2022.1 English

Vivado Design Suite Tcl Command Reference Guide (UG835)

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2022.1 English

Reset switching activity on specified objects


reset_switching_activity [‑default] [‑type <args>] [‑hier] [‑all]
    [‑no_deassert_resets] [‑quiet] [‑verbose] [<objects>...]


Name Description
[-default] Reset default static probability and default toggle rate
[-type] Specify nodes in a specific category. List of valid type values: io_output, io_bidir_enable, register, lut_ram, lut, dsp, bram_enable, bram_wr_enable, gt_txdata, gt_rxdata.
[-hier] Hierarchically resets the switching activity on a hierarchical cells provided as <objects>.
[-all] Reset switching activity on all nets
[-no_deassert_resets] A switch to undo the deassertion of resets via command set_switching_activity -deassert_resets
[-quiet] Ignore command errors
[-verbose] Suspend message limits during command execution
[<objects>] Objects to reset switching activity on


Power, XDC


Resets the attributes of the switching activity on specified nets, ports, pins, and cells in the design.

The switching activity is defined using the set_switching_activity command. The current switching activity defined for a specific port, pin, net, or cell can be found by using the report_switching_activity command.

Note: The reset_switching_activity is used to reset switching activity for specified objects. Use set_switching_activity -default_toggle_rate or -default_static_probability to change or reset the default values for the current design.

This command operates silently and does not return direct feedback of its operation.


-default - (Optional) Reset the static probability and signal rate of the specified object.

-type <arg> - (Optional) Reset the switching activity for the specified type of logic entity. By default, the command is applied to the top-level of the current design, or to the specified <objects>. The -type option applies the command to the specified type of logic objects in the top-level of the current design. The -all option, or -hier option, can be used to modify the scope of objects the command applies to. Valid logic types include:
  • io_output - Primary outputs.
  • io_bidir_enable - Enable pin of Bidir ports.
  • register - All register outputs in the design/hierarchy specified.
  • lut - All LUT outputs in the design/hierarchy specified.
  • lut_ram - All distributed ram outputs in the design/hierarchy specified.
  • dsp - All DSP outputs in the design/hierarchy specified.
  • bram_enable - Enable pins (ENARDEN/ENBWREN) of Block RAMs.
  • bram_wr_enable - Write enables of Block RAMs (WEA/WEBWE).
  • gt_txdata - Output TX data pins of all GTs.
  • gt_rxdata - Output RX data pins of all GTs.

-hier - (Optional) Reset the switching activity across all levels of the specified hierarchical object. Without -hier, the switching activity is applied to the specified <objects> at the current level of the hierarchy.

-all - (Optional) Must be used with -type, reset the switching activity on nets within all instances of the specified -type of logic object.

-no_deassert_resets - (Optional) Disables the -deassert_resets option if it was previously enabled using set_switching_activity.

-quiet - (Optional) Execute the command quietly, returning no messages from the command. The command also returns TCL_OK regardless of any errors encountered during execution.
Note: Any errors encountered on the command-line, while launching the command, will be returned. Only errors occurring inside the command will be trapped.
-verbose - (Optional) Temporarily override any message limits and return all messages from this command.
Note: Message limits can be defined with the set_msg_config command.

<objects> - (Optional) The list of objects for which to reset the switching activity. If not specified, the command resets the switching activity on all objects.


The following example resets the signal_rate and static probability value on all output ports:
reset_switching_activity -default [all_outputs]