m41t81s STMicroelectronics, m41t81s Datasheet - Page 15

• Manufacturer Part Number: m41t81s
• Description: Serial Access Real-time Clock With Alarms
• Manufacturer: STMicroelectronics

Table 2.
0 = Must be set to '0'
ABE = Alarm in Battery Back-up Mode Enable Bit
AF = Alarm Flag (Read only)
AFE = Alarm Flag Enable Flag
BL = Battery Low Bit
BMB0-BMB4 = Watchdog Multiplier Bits
CB = Century Bit
CEB = Century Enable Bit
FT = Frequency Test Bit
HT = Halt Update Bit
OF = Oscillator Fail Flag
OFIE = Oscillator Fail Interrupt Enable
OUT = Output level
RB0-RB1 = Watchdog Resolution Bits
RPT1-RPT5 = Alarm Repeat Mode Bits
RS0-RS3 = SQW Frequency
S = Sign Bit
SQWE = Square Wave Enable
ST = Stop Bit
WDF = Watchdog Flag (Read only)
Addr
0Ah
0Bh
0Ch
0Dh
0Eh
0Fh
00h
01h
02h
03h
04h
05h
06h
07h
08h
09h
10h
11h
12h
13h
RPT4
RPT3
RPT2
RPT1
OFIE
WDF
CEB
OUT
AFE
RS3
D7
ST
0
0
0
0
0
0
0
Clock register map
SQWE
BMB4
RPT5
RS2
0.1 Seconds
CB
HT
D6
FT
AF
0
0
0
0
0
0
Alarm 10 Seconds
10 Years
Alarm 10 Minutes
10 Seconds
10 Minutes
BMB3
ABE
RS1
D5
AI 10 Date
AI 10 Hour
S
0
0
0
0
0
0
10 Hours
10 Date
Al 10M
BMB2
10M
RS0
D4
BL
0
0
0
0
BMB1
D3
0
0
0
0
0
0
Hours (24 Hour Format)
Calibration
Date: Day of Month
Alarm Seconds
BMB0
Alarm Minutes
0.01 Seconds
Alarm Month
D2
OF
Alarm Hour
Alarm Date
0
0
0
0
Seconds
Minutes
Month
Year
Day of Week
RB1
D1
0
0
0
0
0
RB0
D0
0
0
0
0
0
Calibratio
Reserved
Reserved
Reserved
Seconds
Seconds
Watchdo
Al Month
Century/
Minutes
Al Date
Al Hour
Function/Range
Al Sec
Month
Al Min
SQW
Date
Flags
Year
Day
BCD Format
0-1/00-
00-99
00-59
01-12
00-59
01-31
00-99
01-12
01-31
00-23
00-59
00-59
01-7
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