pcf2123 NXP Semiconductors, pcf2123 Datasheet - Page 9

• Manufacturer Part Number: pcf2123
• Description: Spi Real Time Clock/calendar
• Manufacturer: NXP Semiconductors

NXP Semiconductors
Table 4.
Bit positions labelled as - are not implemented and will return a 0 when read. Bit positions labelled with 0 should always be
written with logic 0
[1]
PCF2123_1
Product data sheet
Address
00h
01h
02h
03h
04h
05h
06h
07h
08h
09h
0Ah
0Bh
0Ch
0Dh
0Eh
0Fh
Except in the case of software reset, see
Register name
Control_1
Control_2
Seconds
Minutes
Hours
Days
Weekdays
Months
Years
Minute_alarm
Hour_alarm
Day_alarm
Weekday_alarm
Offset_register
Timer_clkout
Countdown_timer
Registers overview
9.2 Register overview
[1]
.
16 registers are available. The time registers are encoded in the binary coded decimal
format (BCD) to simplify application use. Other registers are either bit-wise or standard
binary.
Bit
7
EXT_TEST
MI
OS
-
-
-
-
-
YEARS (0 to 99)
AEN_M
AEN_H
AEN_D
AEN_W
MODE
-
COUNTDOWN_TIMER
Section 9.5
6
0
SI
SECONDS (0 to 59)
MINUTES (0 to 59)
-
-
-
-
MINUTE_ALARM (0 to 59)
-
-
-
OFFSET
COF2
Rev. 01 — 19 November 2008
5
STOP
MSF
AMPM
HOURS (0 to 23) in 24 h mode
DAYS (1 to 31)
-
-
AMPM
HOUR_ALARM (0 to 23) in 24 h mode
DAY_ALARM (1 to 31)
-
COF1
4
SR
TI_TP
HOURS (1 to 12) in 12 h mode
-
MONTHS (1 to 12)
HOUR_ALARM (1 to 12) in 12 h mode
-
COF0
3
0
AF
-
-
TE
SPI Real time clock/calendar
2
12_24
TF
WEEKDAYS
WEEKDAY_ALARM
-
1
CIE
AIE
CTD1
PCF2123
© NXP B.V. 2008. All rights reserved.
0
0
TIE
CTD0
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