Chapter 6
Additional features
6.1 Low-power mode
For many use cases, such as battery-based smart locks, managing power consumption is critical. Designed with these use cases
in mind, the Smart Lock application preprogrammed on the SLN-VIZN3D-IOT kit supports low-power features out-of-the-box.
6.1.1 Pushbuttons
A user can manually set the SLN-VIZN3D-IOT kit to low-power mode by pressing and holding the SW1 pushbutton located on the
back of the kit for >2 s and then releasing it.
Figure 34. Start low-power mode (SW1 long press)
The screen displays a message and the speaker plays an audio message to confirm that the board is entering sleep mode before
the display turns off.
Figure 35. Entering low-power mode
During low-power mode, the RT117F MCU is set into the SNVS power state -- one of the lowest power modes supported by the
processor -- and almost all onboard components (Flash, RAM…) and external modules (camera, display…) are powered off to
conserve energy. As a result, the USB Serial Interface from the kit will not be active and will not be accessible until the board has
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User Guide
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