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AR# 14065

XST - "WARNING:Xst:753 - <file>.vhd (Line xx). Unconnected output port '<port>' of component '<submodule>'."

Description

Keywords: XST, 753, unconnected, port, VHDL

Urgency: Standard

General Description:
When analyzing the hierarchy of a VHDL design, XST reports the following warning:

"WARNING:Xst:753 - <file>.vhd (Line xx). Unconnected output port '<port>' of component '<submodule>'."

Solution

Unlike input ports, not all outputs of submodules need to be connected. Any unconnected output ports of submodules (and associated logic) are removed during optimization.

This message can be safely ignored if that particular output port is not intended to be used for that particular instantiation of the submodule. Otherwise, be sure that all ports of submodules are properly declared and connected.
AR# 14065
Date Created 03/05/2002
Last Updated 10/20/2005
Status Active
Type General Article