12.12.1. Emulating power down

By writing to bit [0] of the DBGPRCR in either CPU, the debugger causes the processor to assert the DBGNOPWRDWN output. The expected usage model of this signal is that it connects to the system power controller and that, when HIGH, it indicates that this controller must work in emulate mode.

On a power-down request from the processor, if the power controller is in emulate mode, it does not remove processor power or ETM power. Otherwise, it behaves exactly the same as in normal mode.

Emulating power down is ideal for debugging applications running on top of operating systems that are free of errors because the debug register settings are not lost on a power-down event. However, you must ensure that:

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