Philips Semiconductors

PCA8565

Real time clock/calender

Product data

Rev. 01 — 31 March 2003

7 of 26

9397 750 10695

© Koninklijke Philips Electronics N.V. 2003. All rights reserved.

[1]

TF and INT become active simultaneously.

[2]

n = loaded countdown value. Timer stopped when n = 0.

8.6.3

Time and date registers

[1]

The PCA8565 compensates for leap years by adding a 29th day to February if the year counter contains a value which is exactly

divisible by 4, including the year 00.

[1]

These bits may be re-assigned by the user.

Table 8:

INT operation (bit TI/TP = 1)

Source clock (Hz)

INT period (s)[2]

n=1[1]

n>1

4 096

1

⁄

8192

1

⁄

4096

64

1

⁄

128

1

⁄

64

1

1

⁄

64

1

⁄

64

1

⁄

60

1

⁄

64

1

⁄

64

Table 9:

Seconds/VL (address 02H) bits description

Bit

Symbol

Value

Description

7

VL

0

clock integrity is guaranteed

1

integrity of the clock information is no longer guaranteed

6 to 0

seconds

00 to 59

this register holds the current seconds coded in BCD format; example: seconds

register contains x101 1001 = 59 seconds

Table 10:

Minutes (address 03H) bits description

Bit

Symbol

Value

Description

6 to 0

minutes

00 to 59

this register holds the current minutes coded in BCD format

Table 11:

Hours (address 04H) bits description

Bit

Symbol

Value

Description

5 to 0

hours

00 to 23

this register holds the current hours coded in BCD format

Table 12:

Days (address 05H) bits description

Bit

Symbol

Value

Description

5 to 0

days[1]

01 to 31

this register holds the current day coded in BCD format

Table 13:

Weekdays (address 06H) bits description

Bit

Symbol

Value

Description

2 to 0

weekdays[1] 0 to 6

this register holds the current weekday coded in BCD format, see Table 14

Table 14:

Weekday assignments

Day

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

Sunday

xxxxx0

0

0

Monday

xxxxx0

0

1

Tuesday

xxxxx0

1

0

Wednesday

xxxxx0

1

1