PCA2125TS NXP [NXP Semiconductors], PCA2125TS Datasheet - Page 10

• Manufacturer Part Number: PCA2125TS
• Description: SPI Real-time clock/calendar
• Manufacturer: NXP [NXP Semiconductors]

NXP Semiconductors
PCA2125_1
Product data sheet
8.5 Alarm function
Table 16.
Table 17.
Figure 6
When one or several alarm registers are loaded with a valid minute, hour, day or weekday
value and its corresponding alarm enable not bit (AENx) is logic 0, then that information is
compared with the current minute, hour, day and weekday value.
Table 18.
Month
October
November
December
Bit
7 to 0
Bit
7
6 to 0
Fig 6.
shows the data flow and data dependencies starting from the 1 Hz clock tick.
Data flow for the time function
Symbol
YEARS[7:0]
Symbol
AEN_M
MINUTE_ALARM[6:0]
Month assignments
Register Years (address 08h) bit description
Register Minute_alarm (address 09h) bit description
Bit 7
X
X
X
Rev. 01 — 28 July 2008
12_24 hour mode
CALCULATION
LEAP YEAR
Bit 6
Double-digit
Value
00 to 99
X
X
X
…continued
Value
0
1
00 to 59
Bit 5
X
X
X
Description
this register holds the current year value coded in BCD
format
SECONDS
Description
minute alarm is enabled
minute alarm is disabled
this register holds the minute alarm value coded in
BCD format
MINUTES
MONTHS
1 Hz tick
HOURS
YEARS
DAYS
Bit 4
1
1
1
Bit 3
0
0
0
WEEKDAY
SPI Real-time clock/calendar
001aaf901
Bit 2
0
0
0
Digit
PCA2125
© NXP B.V. 2008. All rights reserved.
Bit 1
0
0
1
Bit 0
10 of 36
0
1
0