|
BQ3285EC Datasheet, PDF (5/26 Pages) Texas Instruments – Real-Time Clock (RTC) | |||
|
◁ |
bq3285EC/LC
Programming the RTC
The time-of-day, alarm, and calendar bytes can be writ-
ten in either the BCD or binary format (see Table 2).
These steps may be followed to program the time, alarm,
and calendar:
1. Modify the contents of register B:
a. Write a 1 to the UTI bit to prevent trans-
fers between RTC bytes and user buffer.
b. Write the appropriate value to the data
format (DF) bit to select BCD or binary
format for all time, alarm, and calendar
bytes.
c. Write the appropriate value to the hour
format (HF) bit.
2. Write new values to all the time, alarm, and
calendar locations.
3. Clear the UTI bit to allow update transfers.
On the next update cycle, the RTC updates all 10 bytes
in the selected format.
Table 2. Time, Alarm, and Calendar Formats
Range
Address
0
1
2
3
4
5
6
7
8
9
RTC Bytes
Seconds
Seconds alarm
Minutes
Minutes alarm
Hours, 12-hour format
Hours, 24-hour format
Hours alarm, 12-hour format
Hours alarm, 24-hour format
Day of week (1=Sunday)
Day of month
Month
Year
Decimal
0â59
0â59
0â59
0â59
1â12
0â23
1â12
0â23
1â7
1â31
1â12
0â99
Binary
00Hâ3BH
00Hâ3BH
00Hâ3BH
00Hâ3BH
01HâOCH AM;
81Hâ8CH PM
00Hâ17H
01HâOCH AM;
81Hâ8CH PM
00Hâ17H
01Hâ07H
01Hâ1FH
01Hâ0CH
00Hâ63H
July 1996
5
Binary-Coded
Decimal
00Hâ59H
00Hâ59H
00Hâ59H
00Hâ59H
01Hâ12H AM;
81Hâ92H PM
00Hâ23H
01Hâ12H AM;
81Hâ92H PM
00Hâ23H
01Hâ07H
01Hâ31H
01Hâ12H
00Hâ99H
|
▷ |