Dear Wu Bian, After attaching to a core you might get that output in the “Run Mode“ field of the “State Line“. The message you are likely referring to is “running (power down)“ and the latter relates to the state of the debugger (which is in this particular case running) and at the same time reflects the fact that the core is still not powered. In other words, the TRACE32 software stack and the debugger hardware are able to connect to the debug logic of the target, but the core is still unpowered. It is of course essential to power the core. You can find more information about the latter in debugger_armv8v9.pdf (located in /pdf) on page 94 and 95, or at the following link: https://support.lauterbach.com/kb/articles/arm-what-is-the-meaning-of-the-state-displays-between-after-running. May I ask which SoC you are using precisely? Maybe we have a demo-script for it, which might come in handy. Kind regards, Vittorio Serra