Hey guys
I have used XC6SLX9-3TQG144I in my design. according to data sheet the jtag circuit must be like the illustrated image. I have implemented it in my board.
my problem is that when fpga is not programmed (after connecting power supply) I can program my board successfully. done pin goes high. but after that I can not connect to board with jtag interface. I can not use chipscope. I also can not reprogram it again. could you please tell me what i should do?
What kind of message do you get from your programming tool or chip scope? Are you using Impact to program the part? What programmer are you using?
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Another thought: (this happened to someone I know) if you’ve inadvertently assigned an io port as an output driving low, but it’s connected, say, to a power supply rail, you could be dragging the supply down.