M41ST84W Datasheet, PDF (14/29 Pages) STMicroelectronics – 3.0/3.3V I2C Serial RTC with Supervisory Functions

M41ST84W
Table 3. TIMEKEEPER^® Register Map
Data
Address
D7
D6
D5
D4
D3
D2
D1
D0
Function/Range
BCD Format
00h
0.1 Seconds
0.01 Seconds
Seconds
00-99
01h
ST
10 Seconds
Seconds
Seconds
00-59
02h
0
10 Minutes
Minutes
Minutes
00-59
03h
CEB CB
10 Hours
Hours (24 Hour Format)
Century/Hours 0-1/00-23
04h
TR
0
0
0
0
Day of Week
Day
01-7
05h
0
0
10 Date
Date: Day of Month
Date
01-31
06h
0
0
0
10M
Month
Month
01-12
07h
10 Years
Year
Year
00-99
08h
OUT FT
S
Calibration
Control
09h
WDS BMB4 BMB3 BMB2 BMB1 BMB0 RB1 RB0
Watchdog
0Ah
AFE SQWE ABE Al 10M
Alarm Month
Al Month
01-12
0Bh
RPT4 RPT5
AI 10 Date
Alarm Date
Al Date
01-31
0Ch RPT3 HT
AI 10 Hour
Alarm Hour
Al Hour
00-23
0Dh RPT2
Alarm 10 Minutes
Alarm Minutes
Al Min
00-59
0Eh
RPT1
Alarm 10 Seconds
Alarm Seconds
Al Sec
00-59
0Fh
WDF AF
0
BL
0
0
0
0
Flags
10h
0
0
0
0
0
0
0
0
Reserved
11h
0
0
0
0
0
0
0
0
Reserved
12h
0
0
0
0
0
0
0
0
Reserved
13h
RS3 RS2 RS1 RS0
0
0
0
0
SQW
Keys: S = Sign Bit
FT = Frequency Test Bit
ST = Stop Bit
0 = Must be set to zero
BL = Battery Low Flag (Read only)
BMB0-BMB4 = Watchdog Multiplier Bits
CEB = Century Enable Bit
CB = Century Bit
OUT = Output level
AFE = Alarm Flag Enable Flag
RB0-RB1 = Watchdog Resolution Bits
WDS = Watchdog Steering Bit
ABE = Alarm in Battery Back-Up Mode Enable Bit
RPT1-RPT5 = Alarm Repeat Mode Bits
WDF = Watchdog flag (Read only)
AF = Alarm flag (Read only)
SQWE = Square Wave Enable
RS0-RS3 = SQW Frequency
HT = Halt Update Bit
TR = t_rec Bit
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