NGDBuild will report the following error when using an IBUF_LVCMOS25:
WARNING:NgdBuild:488 - Attribute value "LVCMOS2" is not an accepted value for
attribute "IOSTANDARD" on "<inst>".
The IBUF_LVCMOS25 primitive is no longer supported and never was supported for Virtex-4 or Virtex-5 devices.
This primitive is contained in the Virtex Library. The Virtex family used LVCMOS2 not LVCMOS25 as the IOSTANDARD attribute. This message is issued as a warning because the LVCMOS2 will be replaced by the default IOSTANDARD LVCMOS25.
Do not use the IBUF_LVCMOS25 primitive. Use the IBUF primitive and explicitly define the IOSTANDARD attribute. Only primitives that are listed in the Libraries Guides should be used.
The Library Guides are contained in our software manuals:
Make sure that you reference the correct Libraries Guide for the device you are using. If you do not see a specific Libraries Guide for your device, use the document titled "Libraries Guide."