bq3285ED/LD
This bit inhibits the transfer of RTC bytes to the user
buffer:
AIE = 1 and AF = 1
PIE = 1 and PF = 1
1 = Inhibits transfer and clears UIE
0 = Allows transfer
UIE = 1 and UF = 1
Reading register C clears this bit.
Register C
Register D
Register C Bits
Register D Bits
7
6
5
4
3
0
2
-
1
0
0
0
7
6
0
5
4
3
2
1
0
INTF PF
AF
UF
VRT
DA5 DA4 DA3 DA2 DA1 DA0
Register C is the read-only event status register.
Register D provides for the read-only data integrity
status bit, and the day-of-the-month alarm.
Bits 0, 1, 2, 3 - Unused Bits
Bits 6 - Unused Bit
7
-
6
-
5
-
4
-
3
0
2
-
1
0
0
0
7
-
6
0
5
-
4
-
3
-
2
-
1
-
0
-
These bits are always set to 0.
This bit is always set to 0.
UF - Update Event Flag
VRT - Valid RAM and Time
7
-
6
-
5
-
4
3
-
2
-
1
-
0
-
UF
7
6
-
5
-
4
-
3
2
-
1
-
0
-
VRT
-
This bit is set to a 1 at the end of the update cycle.
Reading register C clears this bit.
1 = Valid backup energy source
0 = Backup energy source is depleted
AF - Alarm Event Flag
7
-
6
-
5
4
-
3
-
2
-
1
-
0
-
When the backup energy source is depleted (VRT = 0),
data integrity of the RTC and storage registers is not
guaranteed.
AF
This bit is set to a 1 when an alarm event occurs. Read-
ing register C clears this bit.
DA0–DA5
7
-
6
-
5
4
3
2
1
0
PF - Periodic Event Flag
DA5 DA4 DA3 DA2 DA1 DA0-
7
-
6
5
-
4
-
3
-
2
-
1
-
0
-
These bits store the value for the day-of-the-month
alarm. If DA0–DA5 are set to zero, then the day-of-the-
month alarm is disabled . These bits are not affected by
a reset.
PF
This bit is set to a 1 every tPI time, where tPI is the time
period selected by the settings of RS0–RS3 in register A.
Reading register C clears this bit.
INTF - Interrupt Request Flag
7
6
-
5
-
4
-
3
-
2
-
1
-
0
-
INTF
This flag is set to a 1 when any of the following is true:
July 1997
10
TI [ TEXAS INSTRUMENTS ]
