When commissioning PCF8563T, the customer found that VL bit of VL_seconds register of some chips was read as 0 when it was powered on for the first time. Theoretically, it should be 1.
The hardware side of the customer has done the timing test, and confirmed that there is no problem with the IIC timing. The hardware iic is used for communication. Not all chips are like this, and some chips have this phenomenon. Please help
Take a look at how to locate the problem and solve the customer's problem, and give some suggestions or doubts, thank you!