12.12.2. Emulating power down

By writing to bit [0] of the PRCR, the debugger asserts the DBGNOPWRDWN output. The expected usage model of this signal is that it is connected to the system power controller and that, when HIGH, it indicates that this controller can work in emulate mode.

If on a power-down request from the processor, the power controller is in emulate mode. It does not remove core or ETM power but, 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, there are a number of disadvantages such as:

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