PCF8523_12 Datasheet, PDF (21/75 Pages) NXP Semiconductors – Real-Time Clock (RTC) and calendar

NXP Semiconductors
PCF8523
Real-Time Clock (RTC) and calendar
OS = 1 and flag can not be cleared
V_DD
OS = 1 and flag can be cleared
oscillation
OS flag
Fig 12. OS flag
OS flag cleared
by software
oscillation now stable
OS flag set when
oscillation stops
t
013aaa319
8.6.2 Register Minutes
Table 14. Minutes - minutes register (address 04h) bit description
Bit
Symbol
Value
Place value Description
7
-
-
-
unused
6 to 4 MINUTES
3 to 0
0 to 5
0 to 9
ten’s place actual minutes coded in BCD
unit place ^format
8.6.3 Register Hours
Table 15. Hours - hours register (address 05h) bit description
Bit
Symbol
Value
Place value Description
7 to 6 -
-
-
unused
12 hour mode^[1]
5
AMPM
0
-
indicates AM
1
-
indicates PM
4
HOURS
3 to 0
0 to 1
0 to 9
ten’s place actual hours in 12 hour mode
unit place ^{coded in BCD format}
24 hour mode^[1]
5 to 4 HOURS
3 to 0
0 to 2
0 to 9
ten’s place actual hours in 24 hour mode
unit place ^{coded in BCD format}
[1] Hour mode is set by bit 12_24 in register Control_1 (see Table 7).
8.6.4 Register Days
Table 16. Days - days register (address 06h) bit description
Bit
Symbol
Value
Place value Description
7 to 6 -
-
-
unused
5 to 4 DAYS^[1]
0 to 3
ten’s place actual day coded in BCD format
3 to 0
0 to 9
unit place
[1] If the year counter contains a value, which is exactly divisible by 4 (including the year 00), the PCF8523
compensates for leap years by adding a 29^th day to February.
PCF8523
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 4 — 5 July 2012
© NXP B.V. 2012. All rights reserved.
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