PCF2127AT/1 NXP [NXP Semiconductors], PCF2127AT/1 Datasheet - Page 30

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

NXP Semiconductors
PCF2127A_2
Product data sheet
8.9.6 Register Months
8.9.7 Register Years
8.9.8 Setting and reading the time
Table 26.
Table 27.
Table 28.
Figure 17
During read/write operations, the time counting circuits (memory locations 03h through
09h) are blocked.
This prevents
Bit
7 to 5 -
4
3 to 0
Month
January
February
March
April
May
June
July
August
September
October
November
December
Bit
7 to 4 YEARS
3 to 0
•
•
Faulty reading of the clock and calendar during a carry condition
Incrementing the time registers during the read cycle
Symbol
MONTHS
Symbol
shows the data flow and data dependencies starting from the 1 Hz clock tick.
Months - months register (address 08h) bit description
Month assignments in BCD format
Years - years register (address 09h) bit description
Upper-digit
(ten’s place)
Bit 4
0
0
0
0
0
0
0
0
0
1
1
1
All information provided in this document is subject to legal disclaimers.
Rev. 02 — 7 May 2010
Value
-
0 to 1
0 to 9
Value
0 to 9
0 to 9
Digit (unit place)
Bit 3
0
0
0
0
0
0
0
1
1
0
0
0
Place value Description
-
ten’s place
unit place
Place value Description
ten’s place
unit place
Bit 2
0
0
0
1
1
1
1
0
0
0
0
0
Integrated RTC, TCXO and quartz crystal
unused
actual month coded in BCD format, see
Table 27
actual year coded in BCD format
Bit 1
0
1
1
0
0
1
1
0
0
0
0
1
PCF2127A
© NXP B.V. 2010. All rights reserved.
Bit 0
1
0
1
0
1
0
1
0
1
0
1
0
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