Stratix III JTAG Failure

Hi Jack,

Got the Scope & probed the JTAG TDI,TMS, TCK, TDO signals.

I could able to see TDI, TMS are toggling from 0 to 3.3V level.

But TCK is not toggling it is hardly singing from 0V to 0.3V. (Inityially I mentioned the signal name wrongly as TDI). This TCK net is showing 2 Ohms to GND.

This is the reason the JTAG chain is not able to detecting the device.

Also I have tested with other boards & TCK is toggling from 0v to 3.3V.

How to rectify this problem.

I Have the JTAG header which is directly connected to the FPGA.

For your reference I have attached the JTAG interface section of Stratix-III FPGA wth this message.

Expecting your valuable suggestion over here.

Best Reagrds,

Kalidoss