Error (261003): Can't continue the established JTAG communication. Reconnect communications cable and device

Description

Due to a problem in the Quartus® II software 12.1 SP1 and earlier, you may see this error when running the SignalTap™ II Logic Analyzer. This problem occurs due to incorrect optimization of the JTAG TDO path. This problem affects designs targeting Stratix® V, Arria® V, and Cyclone® V devices.

Resolution

To avoid this problem, properly constrain the JTAG TDO path and recompile your design. To properly constrain the JTAG TDO path, add the following constraints to your Synopsys Design Constraints (.sdc) file.

if { [string equal quartus_fit $::TimeQuestInfo(nameofexecutable)] }
{ set_max_delay -to [get_ports { altera_reserved_tdo } ] 0 }

This problem has been fixed and the path is properly constrained beginning with the Quartus II software version 13.0.

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• Error (261003): Can't continue the established JTAG communication. Reconnect communications cable and device.