WHat is GCK & GTS & GSR pins role?

ali_rezaei · ‎02-13-2008

WHat is GCK & GTS & GSR pins role? Can I use them as normal IO?

ayang · ‎07-30-2007

I'm assuming you're asking about the CoolRunner-II or 9500XL. For other device families, the answer may differ.

GCK = global clock
GTS = global tri-state
GSR = global set/reset

These are pins that have access to global routing for these dedicated purposes. This minimizes skew for these signals and frees up general purpose routing resources for other logic.

If these special functions are not used, they can be used as general IO (but their global routing cannot be used for general purpose logic).

/Arthur

ali_rezaei · ‎02-13-2008

I meant XC9500 series, so can you explain more about that ? I am implementing a CPLD evaluaion board and I want to know if there is possibility to use these pins as IO?