I want to move from a Nucleo board to a PCB with a "stand-alone" STM32F7.
The STM32 Hardware Development Guide had great information, but I'm still a bit unclear about some issues:
1. The guide emphasizes that the voltage of VDD_USB and others must stay below VDD during startup. Is there something I have to do, or is this already handled internally?
2. When I attach a backup battery, can I just keep it connected even when running with VDD? The Guide suggests no, but a ST presentations says yes.
3. Is there a reason for disabling the voltage regulator with PDR_ON, or can I just connect it to VDD?
4. For the SDMMC, it is advised to "reference the plane using GND or PWR" - come again?