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CMOS-RAM & RealTime Clock (AT) MC146818

        Index Register (070h)

        Data Registers (071h)

               Address         Meaning
                00h             Seconds
                01h             Alarm-Seconds
                02h             Minutes
                03h             Alarm-Minutes
                04h             Hours
                05h             Alarm-Hours
                06h             Day of Week
                07h             Day
                08h             Month
                09h             Year
                0Ah - 0Dh       Status Registers A - D
                0Eh             Diagnosis status-byte
                0Fh             Interupt
                10h             Disk Type A: & B:
                11h             Reserved
                12h             Disk Type C: & D:
                13h             Reserved
                14H             Configuration byte
                15h - 16h       RAM Size low/high
                17h - 18h       Expansion RAM Size low/high
                19h - 2Dh       Reserved
                2Eh - 2Fh       CMOS-RAM Checksum
                30h - 31h       Extended RAM Size
                32h             Century for date
                33h             Power-on flags
                34h - 3Fh       Reserved