bq769x0 demo 通过IIC与bq769x0通讯，例子中有芯片的配置，iic的底层程序，和电压采集部分的逻辑。(Bq769x0 demo communicate with bq769x0 through IIC, in example, the configuration of the chip, the underlying program of the IIC, and the logic of the voltage acquisition part.)