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Altera_Forum
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17 years ago

Stratix III wierd JTAG Config problem

I've got 2 Stratix III devices in a JTAG chain. If I power the board, I can scan the chain OK and program repeatedly but as soon as I switch off the power and re-apply, JTAG no longer works. i...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

i have the same problem on 3 prototype StratixIII boards. We use EP3SL340F1517C3N on own-designed board.

When VCCPGM is below 3.27V the JTAG chain is not detected.

When VCCPGM is over 3.28V, upto 3.75V, the JTAG communication and EPCS programming works fine!

Please let me know if you can reproduce this. I am busy with Altera Support issue to get this resolved, but we are not making much progress here.