DS1689/DS1693

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When 5-volt operation is selected, the device is fully accessible and data can be written and read only

When 3-volt operation is selected and applied within normal limits, the device is fully accessible and data

SQW pins, all inputs are ignored and all outputs are in a high impedance state.

RTC ADDRESS MAP

The address map for the RTC registers of the DS1689/DS1693 is shown in Figure 2. The address map

consists of the 14-clock/calendar registers. Ten registers contain the time, calendar, and alarm data, and

four bytes are used for control and status. All registers can be directly written or read except for the

following:

1. Registers C and D are read-only.

2. Bit 7 of Register A is read-only.

3. The high order bit of the seconds byte is read-only.

DS1689 REAL TIME CLOCK ADDRESS MAP Figure 2