get_hw_vios - 2023.2 English

Vivado Design Suite Tcl Command Reference Guide (UG835)

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2023.2 English

Get a list of hardware VIOs.


get_hw_vios [‑of_objects <args>] [‑regexp] [‑nocase] [‑filter <arg>]
    [‑quiet] [‑verbose] [<patterns>]


Hardware VIOs


Name Description
[-of_objects] Get 'hw_vio' objects of these types: 'hw_device'.
[-regexp] Patterns are full regular expressions
[-nocase] Perform case-insensitive matching. (valid only when -regexp specified)
[-filter] Filter list with expression
[-quiet] Ignore command errors
[-verbose] Suspend message limits during command execution
[<patterns>] Match the 'hw_vio' objects against patterns. Default: *


Hardware, Object


Returns the Virtual Input/Output (VIO) debug core objects that are defined on the current hardware device, hw_device.

The Virtual Input/Output (VIO) debug core can both monitor and drive internal signals on a programmed AMD FPGA in real time. In the absence of physical access to the target hardware, you can use this debug feature to drive and monitor signals that are present on the physical device.

The VIO core has hardware probes, hw_probe objects, to monitor and drive specific signals on the design. Input probes monitor signals as inputs to the VIO core. Output probes drive signals to specified values from the VIO core. Values on the debug core are driven onto the signals at the probe using the commit_hw_vio command.

The VIO debug core needs to be instantiated in the RTL code, therefore you need to know what nets you want monitor and drive prior to debugging the design. The IP catalog provides the VIO core under the Debug category. Detailed documentation on the VIO core can be found in the LogiCORE IP Virtual Input/Output Product Guide (PG159).

This command returns a list of VIO debug core objects on the device, or returns an error if it fails.


-of_objects <arg> - (Optional) Return the VIO debug cores of the specified hardware devices. The devices must be specified as objects using the get_hw_devices or the current_hw_device commands.

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>.
-regexp - (Optional) Specifies that the search <patterns> are written as regular expressions. Both search <patterns> and -filter expressions must be written as regular expressions when this argument is used. Xilinx® regular expression Tcl commands are always anchored to the start of the search string. You can add ".*" to the beginning or end of a search string to widen the search to include a substring. See for help with regular expression syntax.
Note: The Tcl built-in command regexp is not anchored, and works as a standard Tcl command. For more information refer to

-nocase - (Optional) Perform case-insensitive matching when a pattern has been specified. This argument applies to the use of -regexp only.

-filter <args> - (Optional) Filter the results list with the specified expression. The -filter argument filters the list of objects returned by get_hw_vios based on property values on the VIO debug cores. You can find the properties on an object with the report_property or list_property commands. In the case of the "hw_vio" object, "NAME" and "INSTANCE_NAME" are two of the properties that can be used to filter results.

The filter search pattern should be quoted to avoid having to escape special characters. String matching is case-sensitive and is always anchored to the start and to the end of the search string. The wildcard “*” character can be used at the beginning or at the end of a search string to widen the search to include a substring of the property value.
Note: The filter returns an object if a specified property exists on the object, and the specified pattern matches the property value on the object. In the case of the "*" wildcard character, this will match a property with a defined value of "".
For string comparison, the specific operators that can be used in filter expressions are "equal" (==), "not-equal" (!=), "match" (=~), and "not-match" (!~). Numeric comparison operators <, >, <=, and >= can also be used. Multiple filter expressions can be joined by AND and OR (&& and ||). The following gets input pins that do NOT contain the “RESET” substring within their name:
get_pins * -filter {DIRECTION == IN && NAME !~ "*RESET*"}
Boolean (bool) type properties can be directly evaluated in filter expressions as true or not true:
-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.

<patterns> - (Optional) Match hw_vios against the specified patterns. The default pattern is the wildcard '*' which gets a list of all hw_vios available on the current hardware device.


The following example gets the ILA debug cores defined on the current hardware device:

get_hw_vios -of_objects [current_hw_device]