w83977f Winbond Electronics Corp America, w83977f Datasheet - Page 106

• Manufacturer Part Number: w83977f
• Description: Plug & Play 1.0a Compliant
• Manufacturer: Winbond Electronics Corp America

In Bank 1, there are 128 bytes of general purpose user RAM, as shown in table 6.1.2.
TABLE 6.1.2 - REAL TIME CLOCK ADDRESS MAP BANK 1
Bank 2 has 13 registers, 1 Century register, 8 Alarm B registers and 4 control/status registers for "On-
Now" function.
TABLE 6.1.3 - REAL TIME CLOCK "ON-NOW" ADDRESS MAP BANK 2
Time, Calendar, Alarm A, and Alarm B data Modes
ADDRESS
ADDRESS
Register 00h
Register 01h
Register 02h
Register 03h
Register 04h
REGISTER
LOCATION
00h-7Fh
4Ah
4Bh
4Ch
40h
41h
42h
43h
44h
45h
46h
47h
48h
49h
Seconds
Sec. Alarm A
Minutes
Min. Alarm A
Hours
(12-Hour Mode)
(24-Hour Mode)
FUNCTION
REGISTER TYPE
REGISTER TYPE
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
00h-3Bh
00h-3Bh
00h-3Bh
00h-3Bh
01h-0Ch(AM)
81h-8Ch(PM)
00h-17h
BINARY
RANGE(DATA MODE)
- 94 -
Register 0h-7Fh : user RAM
Register 40h : Centuries
Register 41h : Seconds Alarm B
Register 42h : Minutes Alarm B
Register 43h : Hours Alarm B
Register 44h : Day of Week Alarm B
Register 45h : Date of Month Alarm B
Register 46h : Month Alarm B
Register 47h : Year Alarm B
Register 48h : Century Alarm B
Register 49h : "On-Now" Control Register 1
Register 4Ah : "On-Now" Control Register 2
Register 4Bh : "On-Now" Status Register 3
Register 4Ch : "On-Now" Control/Status Register 4
00h-59h
00h-59h
00h-59h
00h-59h
01h-12h(AM)
81h-92h(PM)
00h-23h
BCD
W83977F/ W83977AF
REGISTER FUNCTION
REGISTER FUNCTION
Publication Release Date: January 1997
BINARY
1Eh
1Eh
1Eh
1Eh
08h
08h
EXAMPLE
PRELIMINARY
Revision 0.50
BCD
30h
30h
30h
30h
08h
08h