xilinx 出现Undefined symbol 'IBUFDS' Undefined symbol 'BUFG'.
2010-11-12 15:38
Reason: the symbol or type is not declared in the VHDL source file。
Please declared the symbol or type,usually declared : library ieee; use ieee.std_logic_1164.all; use ieee.numeric_std.all; library UNISIM; use UNISIM.VCOMPONENTS.ALL;