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FM

31

64

FM3130 Integrated RTC/Alarm with 64Kb FRAM

Rev. 3.2

Sept. 2011

Page 10 of 22

09h

Alarm – Seconds

D7

D6

D5

D4

D3

D2

D1

D0

M

10 sec.2

10 sec.1

10 sec.0

Seconds.3

Seconds.2

Seconds.1

Seconds.0

Contains the alarm value for the seconds and the mask bit to select or deselect the Seconds value.

/M

Match: Setting this bit to a „0‟ causes the Seconds value to be used in the alarm match logic. Setting this bit to a

„1‟ causes the match circuit to ignore the Seconds value. Battery-backed, read/write.

08h

Timekeeping – Years

D7

D6

D5

D4

D3

D2

D1

D0

10 year.3

10 year.2

10 year.1

10 year.0

Year.3

Year.2

Year.1

Year.0

Contains the lower two BCD digits of the year. Lower nibble contains the value for years; upper nibble contains

the value for 10s of years. Each nibble operates from 0 to 9. The range for the register is 0-99. Battery-backed,

read/write.

07h

Timekeeping – Months

D7

D6

D5

D4

D3

D2

D1

D0

0

0

0

10 Month

Month.3

Month.2

Month.1

Month.0

Contains the BCD digits for the month. Lower nibble contains the lower digit and operates from 0 to 9; upper

nibble (one bit) contains the upper digit and operates from 0 to 1. The range for the register is 1-12. Battery-

backed, read/write.

06h

Timekeeping – Date of the month

D7

D6

D5

D4

D3

D2

D1

D0

0

0

10 date.1

10 date.0

Date.3

Date.2

Date.1

Date.0

Contains the BCD digits for the date of the month. Lower nibble contains the lower digit and operates from 0 to 9;

upper nibble contains the upper digit and operates from 0 to 3. The range for the register is 1-31. Battery-backed,

read/write.

05h

Timekeeping – Day of the week

D7

D6

D5

D4

D3

D2

D1

D0

0

0

0

0

0

Day.2

Day.1

Day.0

Lower nibble contains a value that correlates to day of the week. Day of the week is a ring counter that counts

from 1 to 7 then returns to 1. The user must assign meaning to the day value, as the day is not integrated with the

date. Battery-backed, read/write.

04h

Timekeeping – Hours

D7

D6

D5

D4

D3

D2

D1

D0

0

0

10 hours.1

10 hours.0

Hours.3

Hours2

Hours.1

Hours.0

Contains the BCD value of hours in 24-hour format. Lower nibble contains the lower digit and operates from 0 to

9; upper nibble (two bits) contains the upper digit and operates from 0 to 2. The range for the register is 0-23.

Battery-backed, read/write.

03h

Timekeeping – Minutes

D7

D6

D5

D4

D3

D2

D1

D0

0

10 min.2

10 min.1

10 min.0

Min.3

Min.2

Min.1

Min.0

Contains the BCD value of minutes. Lower nibble contains the lower digit and operates from 0 to 9; upper nibble

contains the upper minutes digit and operates from 0 to 5. The range for the register is 0-59. Battery-backed,

read/write.

02h

Timekeeping – Seconds

D7

D6

D5

D4

D3

D2

D1

D0

0

10 sec.2

10 sec.1

10 sec.0

Seconds.3

Seconds.2

Seconds.1

Seconds.0

Contains the BCD value of seconds. Lower nibble contains the lower digit and operates from 0 to 9; upper nibble

contains the upper digit and operates from 0 to 5. The range for the register is 0-59. Battery-backed, read/write.

01h

CAL/Control

D7

D6

D5

D4

D3

D2

D1

D0

OSCEN

-

CALS

CAL.4

CAL.3

CAL.2

CAL.1

CAL.0

/OSCEN

Oscillator Enable. When set to 1, the oscillator is halted. When set to 0, the oscillator runs. Disabling the

is internally set to 1, which turns off the oscillator. Battery-backed, read/write.