MKI100-12F8, MKI41KT56S00/20, MKI41T56

bit static CMOS RAM organized as 64 words by 8 bits. A built-in 32.768 kHz oscillator (external crystal controlled) and the first 8 bytes of the RAM are used for the clock/calendar function and are configured in binary coded decimal (BCD) format. Addresses and data are transferred serially via a two-line bi-directional bus. The built-in address register is incremented automatically after each write or read data byte. The MK41T56 clock has a built-in power sense circuit which detects power failures and automatically switches to the battery supply during power failures. The energy needed to sustain the RAM and clock operations can be supplied from a small lithium button cell.