Functional Description

Battery Backed Up RAM and Clock

The MK48T08 RAM and clock chip is a 28-pin package that provides

A time-of-day clock

An oscillator

A crystal

Power fail detection

Memory write protection

8KB of RAM

A battery

The clock provides

Seconds, minutes, hours, day, date, month, and year in BCD 24-hour format

Automatic corrections for 28-, 29- (leap year), and 30-day months

No interrupts are generated by the clock.

The MK48T08 is an 8 bit device; however, the interface provided by the PCCchip2 supports 8-, 16-, and 32-bit accesses to the MK48T08.

Refer to the MK48T08 data sheet for detailed programming information.

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Motorola MVME187 manual Battery Backed Up RAM and Clock