Using the STARTUP Symbol

The Xilinx STARTUP macro gives you external control of the following.

• Global Set/Reset (GSR) for Spartan/XL, 4000E, 4000EX/XL/XV
  
  
• Global Reset (GR) for XC5200
  
  
• Global tri-state control (referenced as GTS in the Verilog files)
  
  
• The user configuration clock
  
  

Instantiating a STARTUP symbol in your design allows you to optionally control these functions from an external pin. However, regardless of whether you use the STARTUP symbol in your design or not, trigger Global Set/Reset and global tri-state control in your testbench file during simulation. Refer to the “Setting Global Set/Reset and Tri-state Signals (FPGAs)” section of the “Design and Simulation Techniques” chapter.

If using the Spartan/XL, XC4000E/L, XC4000EX/XL/XV, or XC5200 device family, you can use the STARTUP symbol with your design. For details, see the “STARTUP” section in the Xilinx Libraries Guide.