Datasheet

Clock operation M41ST85W
20/43 Doc ID 7531 Rev 11
Table 2. TIMEKEEPER
®
register map
Address
Data
Function/range
BCD format
D7 D6 D5 D4 D3 D2 D1 D0
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 RB0-RB1 = Watchdog resolution bits
FT = Frequency test bit WDS = Watchdog steering bit
ST = Stop bit ABE = Alarm in battery backup mode enable bit
0 = Must be set to zero RPT1-RPT5 = Alarm repeat mode bits
BL = Battery low flag (read only) WDF = Watchdog flag (read only)
BMB0-BMB4 = Watchdog multiplier bits AF = Alarm flag (read only)
CEB = Century enable bit SQWE = Square wave enable
CB = Century bit RS0-RS3 = SQW frequency
OUT = Output level HT = Halt update bit
AFE = Alarm flag enable flag TR = t
rec
bit