Introduction

Debug Interface supports Arm® standard bi-directional Serial Wire Debug (SWD) to pass data to and from the debugger and the target system in a highly efficient and standard way. It provides a probe interface consisting of two signals—TCK and TMS. The TMS signal is bidirectional and carries control information to the adapter and data in both directions. The TCK signal is sourced from the probe.

A basic set of debug features is provided to support software development and system integration:

• Independent breakpoint debugging of each CPU core in the system

• Code execution tracing

• Software instrumentation

• The debug features can be controlled via a SWD access port, using industry-standard debugging tools, providing all the normal debug and test functionality

Features

• Two-pin SWD interface, SWO is not supported.

• Support Arm SWD mode for SW-DP.

• Direct debug access to all memories, registers, and peripherals.

• No target resources are required for the debugging session.

• The KM4 supports 4 instruction breakpoints that can be used to remap instruction addresses for code patches and 1 data watchpoint that can be used as trigger.

• The KR4 supports 8 debug triggers.

• After disabled by hardware, debug interface can never be enabled again.

• SWD password mode:

  • SWD password protection, up to 128-bit password length

  • SWD password protected by the secure OTP

  • Dedicated CTRL-AP to receive a password from debugging probe