MC146818A - Motorola

MC146818A REAL-TIME CLOCK PLUS RAM

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Features

a complete time-of-day clock with alarm and one hundred year calendar, a programmable periodic interrupt and square-wave generator, and 50 bytes of low-power static RAM. The MC146818A uses high-speed CMOS technology to interface with 1 MHz processor buses, while consuming very little power. The Real-Time Clock plus RAM has two distinct uses. First, it is designed as a battery powered CMOS part (in an otherwise NMOS/TTL system) including all the common battery backed-up functions such as RAM, time, and calendar. Secondly, the MC146818A maybe used with a CMOS microprocessor to relieve the softw.