DS1306

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FUNCTION TABLE Table 3

MODE

CE

SCLK

SDI

SDO

Disable Reset

L

Input Disabled

Input Disabled

High Z

Write

H

CPOL=1*

CPOL=0

Data Bit Latch

High Z

Read

H

CPOL=1

CPOL=0

X

Next data bit

shift**

* CPOL is the “Clock Polarity” bit that is set in the control register of the microcontroller.

** SDO remains at High Z until 8 bits of data are ready to be shifted out during a read.

NOTE:

CPHA bit polarity (if applicable) may need to be set accordingly.

SERIAL CLOCK AS A FUNCTION OF MICROCONTROLLER

CLOCK POLARITY (CPOL) Figure 6