Datasheet

PCF8523 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2013. All rights reserved.
Product data sheet Rev. 6 — 17 September 2013 22 of 78
NXP Semiconductors
PCF8523
Real-Time Clock (RTC) and calendar
8.6.5 Register Weekdays
[1] Definition may be reassigned by the user.
8.6.6 Register Months
Table 17. Weekdays - weekdays register (address 07h) bit description
Bit Symbol Value Description
7 to 3 - - unused
2to0 WEEKDAYS 0to6 actual weekday, values seeTabl e 18
Table 18. Weekday assignments
Day
[1]
Bit
2 1 0
Sunday 0 0 0
Monday 0 0 1
Tuesday 0 1 0
Wednesday 0 1 1
Thursday 1 0 0
Friday 1 0 1
Saturday110
Table 19. Months - months register (address 08h) bit description
Bit Symbol Value Place value Description
7 to 5 - - - unused
4 MONTHS 0 to 1 ten’s place actual month coded in BCD
format; assignments see Table 20
3 to 0 0 to 9 unit place
Table 20. Month assignments in BCD format
Month Upper-digit
(ten’s place)
Digit (unit place)
Bit Bit
4 3 2 1 0
January 0 0 0 0 1
February 0 0 0 1 0
March 0 0 0 1 1
April00100
May00101
June00110
July00111
August01000
September 0 1 0 0 1
October10000
November10001
December10010