W83977F-A Datasheet, PDF (106/182 Pages) Winbond – WINBOND I/O

W83977F-A/ W83977G-A/ W83977AF-A/ W83977AG-A
Time, Calendar, Alarm A, and Alarm B data Modes continued
REGISTER
FUNCTION
RANGE(DATA MODE)
LOCATION
BINARY
BCD
Register 05h
Hours Alarm A 01h-0Ch(AM)
(12-Hour Mode) 81h-8Ch(PM)
(24-Hour Mode) 00h-17h
01h-12h(AM)
81h-92h(PM)
00h-23h
Register 06h Day of Week 01h-07h
01h-07h
Register 07h Date of Month 01h-1Fh
01h-31h
Register 08h Month
01h-0Ch
01h-12h
Register 09h Year
00h-63h
00h-99h
Register 40h Century
00h-63h
00h-99h
Register 41h Sec. Alarm B 00h-3Bh
00h-59h
Register 42h Min. Alarm B 00h-3Bh
00h-59h
Register 43h Hours Alarm B 01h-0Ch(AM)
(12-Hour Mode) 81h-8Ch(PM)
(24-Hour Mode) 00h-17h
01h-12h(AM)
81h-92h(PM)
00h-23h
Register 44h Day of Week
Alarm B
01h-07h
01h-07h
Register 45h Date of Month 01h-1Fh
Alarm B
01h-31h
Register 46h Month Alarm B 01h-0Ch
01h-12h
Register 47h Year Alarm B 00h-63h
00h-99h
Register 48h Century Alarm 00h-63h
B
00h-99h
EXAMPLE
BINARY
BCD
08h
08h
08h
08h
02h
02h
04h
04h
07h
07h
61h
97h
13h
19h
1Eh
30h
1Eh
30h
08h
08h
08h
08h
02h
02h
04h
04h
07h
07h
61h
97h
13h
19h
9.2 Update Cycle
The RTC executes an update cycle once per second. It is in an update cycle when RTC updates the
contents of the clock and calendar registers. In the meantime, RTC also compares each alarm byte
with corresponding timer byte and generates an alarm flag if a match or a don't care condition (0C0h)
is present in the alarm register.
The update-in-progress bit (UIP) in register A pulses high once per second. The update cycle occurs
244μS after the UIP bit goes high. This bit is cleared and the update-ended flag (UF) is set in the end
of an update cycle.
UPDATE CYCLE TIME TABLE
UIP BIT
UPDATE CYCLE TIME (T_UC)
BEFORE UPDATE CYCLE TIME (T_BUC MIN)
1
1984μS
-
0
-
244μS
-98