Quick & dirty approach to detect/prevent any attempt to JTAG access. The output signal might will use an almost infinite number of possible options, such as:

◦ Reset the internal MMCM/PLLs
◦ Gate off any internal clocks
◦ Drive the GSR or GTS inputs on the STARTUPEx primitive

#FPGA #Xilinx #JTAG #TamperDetection #protection #security