60.6.3.4.2 Physical Prevention for JTAG Debug

A physical protection has been implemented for JTAG debug. The TMS/SWDIO, TCK/SWCLK and TDI signals are connected directly to the boundary TAP controller, but they can be inhibited on the path to the Debug Access Port (DAP). Thus, to disable the DAP for debug purposes, the JTAGDIS field must be configured in the customer OTP area.

Programming this field prevents JTAG debug irreversibly.