238 www.xilinx.com Virtex-5 FPGA User Guide
UG190 (v5.0) June 19, 2009
Chapter 6: SelectIO Resources
The allowed values for the DIFF_TERM attribute are:
• TRUE
• FALSE (Default)
To specify the DIFF_TERM attribute, set the appropriate value in the generic map (VHDL)
or inline parameter (Verilog) of the instantiated IBUFDS or IBUGDS component. Please
refer to the ISE Language Templates or the Virtex-5 FPGA HDL Libraries Guide for the
proper syntax for instantiating this component and setting the DIFF_TERM attribute.
Virtex-5 FPGA I/O Resource VHDL/Verilog Examples
The VHDL and Verilog example syntaxes to declare a standard for Virtex-5 FPGA I/O
resources are found in the Virtex-5 FPGA Libraries Guide.