PT7C4337A Datasheet, PDF (9/25 Pages) Pericom Semiconductor Corporation – Real-time Clock Module

PT7C4337A/4337AC
Real-time Clock Module (I²C Bus)
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
08 Alarm 1: Minutes
A1M2^*2
M40
M20
M10
M8
M4
M2
M1
09 Alarm 1: Hours
0A Alarm 1: Day, Date
0B Alarm 2: Minutes
A1M3^*2 12, /24 ^{H20 or}
H10
H8
H4
H2
H1
P, /A
A1M4^*2
Day,
0,
0,
0,
W4,
W2,
W1,
/Date
D20
D10
D8
D4
D2
D1
A2M2^*3
M40
M20
M10
M8
M4
M2
M1
0C Alarm 2: Hours
0D Alarm 2: Day, Date
0E Control
A2M3^*3 12, /24
A2M4^*3
/ETIME^*4
Day,
/Date
0
H20 or
P, /A
0,
D20
0
H10
0,
D10
RS2^*5
H8
0,
D8
RS1^*5
H4
H2
W4,
W2,
D4
D2
INTCN^*6 A2IE^*7
H1
W1,
D1
A1IE^*7
0F Status
OSF^*9
0
0
0
0
0
A2F^*8
A1F^*8
Caution points:
*1. PT7C4337A uses 8 bits for address. For excess 0FH address, PT7C4337A will not respond (no acknowledge signal was given).
*2. Alarm 1 mask bits. Select alarm repeated rate when an alarm occurs.
*3. Alarm 2 mask bits. Select alarm repeated rate when an alarm occurs.
*4. Oscillator and time count chain enable/disable bit.
*5. Square wave output frequency select.
*6. Interrupt output pin select bit.
*7. Alarm 1 and alarm 2 enable bits.
*8. Alarm 1 and alarm 2 flag bits.
*9. Oscillator stops flag.
*10. All bits marked with "0" are read-only bits. Their value when read is always "0".
Control and status register
Addr.
Description
D7
D6
(hex)
0E
Control
/ETIME
0
(default)
0
0
0F
Status
(default)
OSF
0
1
0
D5
D4
D3
D2
D1
D0
0
RS2
RS1
INTCN A2IE
A1IE
0
1
1
0
0
0
0
0
0
0
A2F
A1F
0
0
0
0
Undefined Undefined
Oscillator related bits
 /ETIME
Enable oscillator and time count chain bit.
/ETIME
Data
Description
Read / Write
0 Enable oscillator and time count chain.
1 Disable oscillator and time count chain.
Default
 OSF
Oscillator Stops Flag.
A logic 1 in this bit indicates that the oscillator either is stopped or was stopped for some period of time and may be used to judge
the validity of the clock and calendar data. This bit is set to logic 1 anytime that the oscillator stops. The following are examples
of conditions that can cause the OSF bit to be set:
1) The first time power is applied.
2) The voltage present on VCC is insufficient to support oscillation.
3) The /ETIME bit is turned off.
4) External influences on the crystal (e.g., noise, leakage, etc.).
This bit remains at logic 1 until written to logic 0.
2014-10-0002
PT0480-2 11/03/14
9