ATtiny817 Xplained Pro Qtouch PTC sleep mode

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The title summarizes all of my questions: I am designing a custom board with Qtouch buttons that should stay in sleep mode until enabled by touching the Power On button. I am using the ATtiny817 Xplained pro board for evaluation purposes. So far the Qtouch buttons work perfectly, but the intended power down functionality is a complete mystery to me. There is a lot of Atmel/Microchip literature describing the possibilities to disable everything else and use a single Qtouch button in sleep mode to wake up the processor. There are references to watchdog timer and event system.

The QTouch® Modular Library Peripheral Touch Controller User's Guide (DS40001986B) vaguely mentions the following function:


touch_ret_t qtm_autoscan_sensor_node(qtm_auto_scan_config_t* qtm_auto_scan_config_ptr, void (*auto_scan_callback)(void));


Purpose: Configures the PTC for sleep mode measurement of a single node, with windowcomparator wake


Question: Will this automatically configure event system and WDT as needed? Is there any sample code or more detailed description available that puts this into a working context? I have extensively searched the Microchip website but so far did not find anything.


Remark: The Atmel QTouch Library Peripheral Touch Controller [USER GUIDE]  on page 12 shows a diagram "Figure 3-8. Low Power Flow". I do not understand how the above mentioned function will fit into this flow diagram. The user guide however does not apply to ATtiny devices so the program flow might be different there.


Any help is greatly appreciated!