PCF2127AT/1 NXP [NXP Semiconductors], PCF2127AT/1 Datasheet - Page 29

• Manufacturer Part Number: PCF2127AT/1
• Description: Integrated RTC, TCXO and quartz crystal
• Manufacturer: NXP [NXP Semiconductors]

NXP Semiconductors
PCF2127A_2
Product data sheet
8.9.3 Register Hours
8.9.4 Register Days
8.9.5 Register Weekdays
Table 22.
[1]
Table 23.
[1]
Table 24.
Although the association of the weekdays counter to the actual weekday is arbitrary, the
PCF2127A will assume Sunday is 000 and Monday is 001 for the purposes of determining
the increment for calendar weeks.
Table 25.
[1]
Bit
7 to 6 -
12 hour mode
5
4
3 to 0
24 hour mode
5 to 4 HOURS
3 to 0
Bit
7 to 6 -
5 to 4 DAYS
3 to 0
Bit
7 to 3 -
2 to 0 WEEKDAYS
Day
Sunday
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Hour mode is set by the bit 12_24 in register Control_1.
The RTC compensates for leap years by adding a 29
which is exactly divisible by 4, including the year 00.
These bits may be re-assigned by the user.
[1]
Symbol
AMPM
HOURS
Symbol
Symbol
Hours - hours register (address 05h) bit description
Days - days register (address 06h) bit description
Weekdays - weekdays register (address 07h) bit description
Weekday assignments
[1]
[1]
[1]
All information provided in this document is subject to legal disclaimers.
Bit
2
0
0
0
0
1
1
1
Rev. 02 — 7 May 2010
Value
-
0
1
0 to 1
0 to 9
0 to 2
0 to 9
Value
-
0 to 3
0 to 9
Value
-
0 to 6
Description
unused
actual weekday value, see
Place value Description
-
-
-
ten’s place
unit place
ten’s place
unit place
Place value Description
-
ten’s place
unit place
1
0
0
1
1
0
0
1
Integrated RTC, TCXO and quartz crystal
th
day to February if the year counter contains a value
unused
indicates AM
indicates PM
actual hours coded in BCD format when in
12 hour mode
actual hours coded in BCD format when in
24 hour mode
unused
actual day coded in BCD format
Table 25
PCF2127A
0
0
1
0
1
0
1
0
© NXP B.V. 2010. All rights reserved.
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