What is the minimum JTAG signals that should be routed to my JTAG connector for the MPC5777C debugging to work properly?
TDI, TDO, TMS, TCK, RESET, JTAG Supply voltage reference (VREF), and ground.
JCOMP depends on the debugger that you are using. Some debuggers allow the JCOMP to be pull high on the board and not connected to the JTAG connector. They include a command to override the debugger having to drive the signal. However, some debugger do not include this functionality. You should check with your debugger supplier.
RDY and EVTI are optional signals. RDY allows for faster block moves over the JTAG interface. This can be beneficial during flash programming.
See the MPC5777C Hardware requirements application note:
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