log_wave - 2023.2 English

Vivado Design Suite Tcl Command Reference Guide (UG835)

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2023.2 English

Log simulation output for specified wire, signal, or reg for viewing using Vivado Simulators waveform viewer. Unlike add_wave, this command does not add the waveform object to waveform viewer (i.e. Waveform Configuration). It simply enables logging of output to the Vivado Simulators Waveform Database (WDB).


log_wave [‑recursive] [‑r] [‑verbose] [‑v] [‑quiet] <hdl_objects>...


Name Description
[-recursive] Searches recursively for objects
[-r] Searches recursively for objects
[-verbose] Displays all warnings
[-v] Displays all warnings
[-quiet] Ignore command errors
<hdl_objects> Which hdl_objects to trace



Log simulation activity for the specified HDL objects into the waveform database file (.wdb) for viewing using AMD Vivado™ simulator waveform viewer.

In the Vivado simulator, an HDL object is an entity that can hold a value, such as a wire, signal, or register.

Unlike add_wave, this command does not add the waveform object to waveform configuration. It simply enables logging of waveform activity to the Vivado simulator waveform database (WDB). See the Vivado Design Suite User Guide: Logic Simulation (UG900) for more information.

This command returns nothing.


-recursive | -r - (Optional) Recursively log the waveform activity of the specified HDL objects, and the children of the specified HDL objects.

-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.

<hdl_objects> - (Required) Specifies the HDL objects to include in the Vivado simulator waveform database file. The level of hierarchy is also represented in the hdl_objects pattern. For instance /tb/UUT/* indicates all HDL objects within the /tb/UUT level of the design.


The following example logs the waveform activities for the specified HDL objects.

log_wave -r [get_objects /testbench/dut/*]

See Also