PCF8523 NXP [NXP Semiconductors], PCF8523 Datasheet - Page 7

• Manufacturer Part Number: PCF8523
• Description: Real-Time Clock (RTC) and calendar
• Manufacturer: NXP [NXP Semiconductors]

NXP Semiconductors
Table 4.
Bit positions labeled as - are not implemented and will return a 0 when read. Bit T must always be written with logic 0.
PCF8523
Product data sheet
Address Register name
Control registers
00h
01h
02h
Time and date registers
03h
04h
05h
06h
07h
08h
09h
Alarm registers
0Ah
0Bh
0Ch
0Dh
Offset register
0Eh
Control_1
Control_2
Control_3
Seconds
Minutes
Hours
Days
Weekdays
Months
Years
Minute_alarm
Hour_alarm
Day_alarm
Weekday_alarm
Offset
Registers overview
8.1 Register overview
The 20 registers of the PCF8523 are auto-incrementing after each read or write data byte
up to register 13h. After register 13h, the auto-incrementing will wrap around to address
00h (see
Fig 6.
CAP_SEL T
PM[2:0]
-
-
AE_M
AE_H
AE_D
AE_W
Bit
7
WTAF
OS
-
-
-
YEARS (0 to 99)
MODE
Figure
Auto-incrementing of the registers
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6).
6
CTAF
SECONDS (0 to 59)
MINUTES (0 to 59)
-
-
-
-
MINUTE_ALARM (0 to 59)
-
-
-
-
OFFSET[6:0]
Rev. 3 — 30 March 2011
5
STOP
CTBF
AMPM
HOURS (0 to 23 in 24 hour mode)
DAYS (1 to 31)
-
-
AMPM
HOUR_ALARM (0 to 23 in 24 hour mode)
DAY_ALARM (1 to 31)
-
address register
00h
01h
02h
03h
11h
12h
13h
...
SR
SF
-
-
MONTHS (1 to 12)
HOUR_ALARM (1 to 12 in 12 hour mode)
-
4
HOURS (1 to 12 in 12 hour mode)
auto-increment
12_24
-
3
AF
BSF
-
Real-Time Clock (RTC) and calendar
wrap around
013aaa309
2
SIE
WTAIE
BLF
WEEKDAYS (0 to 6)
WEEKDAY_ALARM (0 to 6)
1
AIE
CTAIE
BSIE
PCF8523
© NXP B.V. 2011. All rights reserved.
0
CIE
CTBIE
BLIE
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