Checking the JTAG Chain Meets Signal Integrity Guidelines

The JTAG signals require termination resistors for correct high-speed operation, and pull-resistors to ensure the chain never becomes active except when the board is being tested. Figure 38 shows a best practice circuit (for more details, see the Defining JTAG Terminations section in the Setting up a Physical JTAG Chain chapter).

Figure 38: Best Practice for JTAG Signal Terminations

XJDeveloper automatically checks that the circuit complies with signal integrity guidelines for these components and will display warnings in the Warnings tab at the bottom of the XJDeveloper window if they are not met. To turn off these warnings, remove the tick from the Check Termination checkbox in the Chain Setup section of the JTAG Chain screen:

Figure 39: Disabling Termination Warnings on the JTAG Chain