General Description: When I instantiate LVCMOS2-type buffers, XST issues some of the following warnings and errors:
"ERROR:NgdBuild:455 - logical net 'ibuf_name' has multiple drivers" "WARNING:NgdBuild:463 - input pad net 'ibuf_name' has an illegal input buffer" "ERROR:NgdBuild:466 - input pad net 'ibuf_name' has illegal connection" "ERROR:NgdBuild:467 - output pad net 'obuf_name' has an illegal buffer"
Solution
When NGDBuild encounters a LVCMOS2-type buffer, it converts it to a LVCMOS25-type buffer. To avoid these warnings and errors, change the component in HDL from an LVCMOS2 to an LVCMOS25.