I'm looking for the datasheet for the SD2403API-G real-time clock chip mainly for the SPI protocol.
It's part of a "fitness wall clock" that I don't have the remote control for. The uC seems to be interrogating the clock chip via SPI several times a second, so I could possibly sniff out how to read the time, but I'd also like to be able to set it.
Would also be interested if anyone has good guess of what the protocol might be... i.e. similar to other RTC devices.