The GSR and GTS signal sources are defined and connected using the STARTUPE2 primitive. This primitive allows the user to define the source of these dedicated nets. GSR and GTS are always active during configuration, and connecting signals to them on the STARTUPE2 primitive defines how they are controlled after configuration. By default, they are disabled after configuration on a selected clock cycle of the start-up phase, enabling the flip-flops and I/Os in the device. The STARTUPE2 primitive also includes other signals used specifically during configuration. For more information, refer to the 7 Series FPGAs Configuration User Guide (UG470).