Control and Status Register Address Bit Map
D7
D6
D5
D4
D3
D2
D1
D0
1. Reset by
writing
1 to bit.
Main Status Register
PS
e
0
R/W
RS
e
0
R/W
1
ADDRESS
e
00H
R/W
1
R/W
R/W
1
R/W
1
R
2
R
3
Page
Select
Register
Select
Timer 1
Interrupt
Timer 0
Interrupt
Alarm
Interrupt
Periodic
Interrupt
Power Fail
Interrupt
Interrupt
Status
2. Set/reset by
voltage at
PFAIL pin.
3. Reset when
all pending
interrupts
are removed.
Timer 0 Control Register
PS
e
0
RS
e
0
Address
e
01H
Count Hold
Gate
Timer
Read
Input Clock
Select C2
Input Clock
Select C1
Input Clock
Select C0
Mode
Select M1
Mode
Select M0
Timer
Start/Stop
All Bits R/W
Timer 1 Control Register
PS
e
0
RS
e
0
Address
e
02H
Count Hold
Gate
Timer
Read
Input Clock
Select C2
Input Clock
Select C1
Input Clock
Select C0
Mode
Select M1
Mode
Select M0
Timer
Start/Stop
All Bits R/W
Periodic Flag Register
PS
e
0
R/W
RS
e
0
Address
e
03H
4. Read Osc fail
Write 0 Batt-
Backed Mode
Write 1 Single
Supply Mode
R/W
4
R
5
R
5
R
5
R
5
R
5
R
5
Test
Mode
Osc. Fail/
Single Supply
1 ms
Flag
10 ms
Flag
100 ms
Flag
Seconds
Flag
10 Second
Flag
Minute
Flag
5. Reset by
positive edge
of read.
Interrupt Routing Register
PS
e
0
R/W
RS
e
0
Address
e
04H
R/W
R
6
R/W
R/W
R/W
R/W
R/W
Time Save
Enable
Low Battery
Flag
Power Fail
Delay
Enable
Timer 1
Int. Route
MFO/INT
Timer 0
Int. Route
MFO/INT
Alarm
Int. Route
MFO/INT
Periodic
Int. Route
MFO/INT
Power Fail
Int. Route
MFO/INT
6. Set and reset
by V
BB
voltage.
Real Time Mode Register
PS
e
0
RS
e
1
Address
e
01H
Crystal
Freq. XT1
Crystal
Freq. XT0
Timers EN
on Back-Up
Interrupt EN
on Back-Up
Clock
Start/Stop
12/24 Hr.
Mode
Leap Year
MSB
Leap Year
LSB
All Bits R/W
Output Mode Register
PS
e
0
RS
e
1
Address
e
02H
MFO as
Crystal
MFO as
Timer 0
MFO
PP/OD
MFO
INTR
PP/OD
INTR
RAM
RAM
All Bits R/W
Active HI/LO
Active HI/LO
Interrupt Control Register 0
PS
e
0
RS
e
1
Address
e
03H
Timer 1
Interrupt
Enable
Timer 0
Interrupt
Enable
1 ms
Interrupt
Enable
10 ms
Interrupt
Enable
100 ms
Interrupt
Enable
Seconds
Interrupt
Enable
10 Second
Interrupt
Enable
Minute
Interrupt
Enable
All Bits R/W
Interrupt Control Register 1
PS
e
0
RS
e
1
Address
e
04H
Power Fail
Interrupt
Enable
Alarm
Interrupt
Enable
DOW
Interrupt
Enable
Month
Interrupt
Enable
DOM
Interrupt
Enable
Hours
Interrupt
Enable
Minute
Interrupt
Enable
Second
Interrupt
Enable
All Bits R/W
20