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Altera_Forum
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17 years ago

Stratix III. Problems with JTAG and Fast AS

Hello all! I have problems with Stratix III configaration on self-made PCB. We use Fast AS with EPCS64 and JTAG. Download cable: USB Blaster (not original ALTERA cable). 1. JTAG detec...
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Altera_Forum
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17 years ago

Another possible reason is this: If your JTAG circuit is very sensitive to on-board generated interferences, it may fail when the design is active and generated interfering signals. Insufficient supply decoupling and FPGA ground connections, long JTAG traces, too high TCK pulldown-resistor are known issues in this regard.