For shutting down the system(?), TWL_FIRM writes u8 value 8 to [[I2C]] MCU register 0x20. For returning to 3DS-mode, TWL_FIRM writes value 4 to that MCU register to trigger a hardware system reboot. | For shutting down the system(?), TWL_FIRM writes u8 value 8 to [[I2C]] MCU register 0x20. For returning to 3DS-mode, TWL_FIRM writes value 4 to that MCU register to trigger a hardware system reboot. |