I am attempting to use the RTC registers in the TPS65910 and having some difficulty. I am properly addressing the device as it ACKs the command and register select bytes. It returns 0x00 for all register reads, even where the default is non-zero. I assume I am doing something wrong. I scoured the data sheet for clues, but found documentation on the I2C operation somewhat sparse. I have some questions:
- How is the register address sent to the PMIC? I am assuming it is sent as the first byte after the address/write command byte. Is this correct?
- Does the register address auto-increment after a byte is written or read? (I tried reading multiple bytes, and also multiple single byte write register address/read a byte operations)
- Is dropping the STOP signal in between the write register address and read command allowed, or must I write the register address with a STOP signal before issuing the read command?
It would be nice if the above information were included in the data sheet and/or an explicit signalling diagram were included.
Gerry Belanger