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Altera_Forum's avatar
Altera_Forum
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8 years ago

JTAG contacts problem

Good afternoon, members of the forum. I have a used card with a Stratix V chip. For a long time I could not get connected by jtag. I decided to use a multimeter to measure the contacts from t...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
8 years ago

Presuming you have checked correct function of your USB Blaster by using it with a different board, I see two possible reasons for JTAG failure

- FPGA is held in POR due to missing or to too low supply voltage for one of the monitored nodes

- FPGA JTAG interface has been damaged

JTAG pull-up and pull-down resistor can be varied in certain range without affecting correct operation.