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Altera_Forum
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17 years ago

Cyclone III problem with USB blaster JTAG communication

Hi all I've spent the last week debugging the jtag connection between the fpga and the usb blaster.:mad: I finally found something that is wrong.:) In JTAG there are 4 signals.. The fi...
Altera_Forum's avatar
Altera_Forum
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17 years ago

Harald has basically answered the question. As an additional remark, TDO input at USB Blaster or any other JTAG interface is supposed to be high impedance and should never short the signal in a way you described. I expect that the PIV3T3254 level converter inside Terasic USB Blaster is defective or a solder short exists inside the adapter.