DS3232 Maxim, DS3232 Datasheet - Page 11

• Manufacturer Part Number: DS3232
• Description: The DS3232 is a low-cost temperature-compensated crystal oscillator (TCXO) with a very accurate, temperature-compensated, integrated real-time clock (RTC) and 236 bytes of battery-backed SRAM
• Manufacturer: Maxim

event, it is possible that the microcontroller and DS3232
I
e.g., the microcontroller resets while reading data from
the DS3232. When the microcontroller resets, the
DS3232 I
by toggling SCL until SDA is observed to be at a high
level. At that point the microcontroller should pull SDA
low while SCL is high, generating a START condition.
If SCL is held low for greater than t
interface is reset. This limits the minimum frequency at
which the I
Figure 1. Address Map for DS3232 Timekeeping Registers and SRAM
Note: Unless otherwise specified, the registers’ state is not defined when power is first applied.
2
ADDRESS
14h–0FFh
C communications could become unsynchronized,
0Ch
0Dh
0Ah
0Bh
0Eh
00h
01h
02h
03h
04h
05h
06h
07h
08h
09h
0Fh
10h
11h
12h
13h
2
C interface may be placed into a known state
2
Century
EOSC
A1M1
A1M2
A1M3
A1M4
A2M2
A2M3
A2M4
DATA
C interface can be operated. If data is
BIT 7
SIGN
SIGN
MSB
OSF
0
0
0
0
0
0
x
BB32kH z
BBSQW
DY/DT
DY/DT
DATA
DATA
DATA
12/24
12/24
12/24
BIT 6
0
0
0
0
x
10 Year
10 Seconds
10 Seconds
10 Minutes
10 Minutes
10 Minutes
20 Hour
20 Hour
20 Hour
C RATE 1
AM/PM
AM/PM
AM/PM
CONV
DATA
DATA
BIT 5
0
0
0
0
x
Extremely Accurate I
10 Date
10 Date
10 Date
IF
____________________________________________________________________
, the internal I
10 Month
CRATE0
10 Hour
10 Hour
10 Hour
DATA
DATA
BIT 4
RS2
0
0
0
x
Integrated Crystal and SRAM
EN32kHz
DATA
DATA
BIT 3
RS1
2
0
0
x
0
C
INTCN
being written to the device when the interface timeout is
exceeded, prior to the acknowledge, the incomplete
byte of data is not written.
The time and calendar information is obtained by read-
ing the appropriate register bytes. Figure 1 illustrates
the RTC registers. The time and calendar data are set
or initialized by writing the appropriate register bytes.
The contents of the time and calendar registers are in
binary-coded decimal (BCD) format. The DS3232 can
be run in either 12-hour or 24-hour mode. Bit 6 of the
DATA
DATA
BIT 2
BSY
Seconds
Seconds
Minutes
Minutes
Minutes
0
0
x
Month
Hour
Date
Year
Hour
Date
Hour
Date
Day
Day
BIT 1
DATA
DATA
A2IE
A2F
Day
0
0
x
DATA
DATA
BIT 0
A1IE
LSB
A1F
0
0
x
Alarm 1 Seconds
Clock and Calendar
Alarm 1 Minutes
Alarm 2 Minutes
Alarm 1 Hours
Alarm 2 Hours
Control/Status
MSB of Temp
Alarm 1 Date
Alarm 2 Date
2
LSB of Temp
Aging Offset
Alarm 1 Day
Alarm 2 Day
FUNCTION
Not used
Seconds
Minutes
Century
Control
C RTC with
Month/
SRAM
Hours
Date
Year
Day
1–12 + AM/PM
1–12 + AM/PM
1–12 + AM/PM
Reserved for
00h–0FFh
RANGE
01–12 +
Century
00–59
00–59
00–23
00–99
00–59
00–59
00–23
00–59
00–23
1–31
1–31
1–31
1–7
1–7
1–7
test
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