M48T35AY, M48T35AV

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Table 11. Register Map

Address

Data

Function/Range

BCD Format

D7

D6

D5

D4

D3

D2

D1

D0

7FFFh

10 Years

Year

Year

00-99

7FFEh

0

0

0

10 M.

Month

Month

01-12

7FFDh

0

0

10 Date

Date

Date

01-31

7FFCh

0

FT

CEB

CB

0

Day

Century/Day

00-01/01-07

7FFBh

0

0

10 Hours

Hours

Hour

00-23

7FFAh

0

10 Minutes

Minutes

Minutes

00-59

7FF9h

ST

10 Seconds

Seconds

Seconds

00-59

7FF8h

W

R

S

Calibration

Control

Keys:

S = SIGN Bit

FT = FREQUENCY TEST Bit (Must be set to ‘0’ upon power for normal operation)

R = READ Bit

W = WRITE Bit

ST = STOP Bit

0 = Must be set to ‘0’

CEB = Century Enable Bit

CB = Century Bit

Note: When CEB is set to ‘1’, CB will toggle from ‘0’ to ‘1’ or from ‘1’ to ‘0’ at the turn of the century (dependent upon the initial value set).

When CEB is set to ‘0’, CB will not toggle.

The WRITE Bit does not need to be set to write to CEB and CB.

Figure 10. Clock Calibration

AI00594B

NORMAL

POSITIVE

CALIBRATION

NEGATIVE

CALIBRATION