W83977G Winbond Electronics Corp America, W83977G Datasheet - Page 107

• Manufacturer Part Number: W83977G
• Description: W83877TF plus KBC, CIR, RTC, Pb-free
• Manufacturer: Winbond Electronics Corp America

Update Period and UIP Timing
9.3
The RTC has four control/status registers. They are accessible at all times.
9.3.1
• All bits are unaffected by RESET.
• Register A is a read/write register except bit 7 (UIP is read only).
UIP : (read only)
When UIP is 1, an update cycle is in progress. The UIP is cleared in the end of an update cycle and
when the SET bit in register B is 1.
DV[2:0] : Divider Control
These three bits are used to control divider and 32KHz oscillator.
RS[3:0 ] : Periodic Interrupt Rate
FREQUENCY
NAME
TIME-BASE
32.768KHZ
32.768KHZ
32.768KHZ
32.768KHZ
32.768KHZ
BIT
W83977F-A/ W83977G-A/ W83977AF-A/ W83977AG-A
REGISTERS
Register 0Ah
UIP
7
DV2
0
0
0
1
1
DV2
6
DV1
0
1
1
0
1
Update Period(1 Second)
DV1
DV0
5
X
X
X
0
1
-99 -
t
DV0
BUC
OPERATION MODE
4
YES
NO
NO
NO
NO
RS3
t
UC
3
Publication Release Date: May 2006
RS2
2
DIVIDER RESET
RS1
1
YES
-
-
-
-
Revision 0.60
RS0
0