tie_unused_pins - 2024.1 English

Vivado Design Suite Tcl Command Reference Guide (UG835)

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2024.1 English

Tie off unused cell pins


tie_unused_pins [‑of_objects <args>] [‑quiet] [‑verbose]


Name Description
[-of_objects] tie unused pins of specified cell(s)
[-quiet] Ignore command errors
[-verbose] Suspend message limits during command execution




Tie up or down the unconnected pins of cells in the open synthesized or implemented design. The command uses an internal process to identify whether a pin should be tied up or down.

This command is intended to tie up or down the unconnected pins of cells added to the netlist with the create_cell command.


-of_objects <args> - (Optional) Tie up or down the unused pins of the specified cell objects.
Note: The -of_objects option requires objects to be specified using the get_* commands, such as get_cells or get_pins, rather than specifying objects by name. In addition, -of_objects cannot be used with a search <pattern>.
-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.


The following example ties the unused pins of cells up or down, depending on their usage:

tie_unused_pins -of_objects [get_cells cpuEngine]