pcf2127a NXP Semiconductors, pcf2127a Datasheet - Page 37

• Manufacturer Part Number: pcf2127a
• Description: Integrated Rtc, Tcxo And Quartz Crystal
• Manufacturer: NXP Semiconductors

NXP Semiconductors
PCF2127A_1
Product data sheet
WDTF is read only. A read of the register Control_2 will automatically reset the flag WDTF.
The watchdog timer flag WDTF is read only and cannot be cleared with the interface.
WDTF can be cleared by
Writing a logic 0 or logic 1 to WDTF has no effect.
Table 37.
WD_CD[1:0]
11
Fig 21. WD_CD[1:0] = 10: watchdog activates an interrupt when timed out
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timer value
When the watchdog timer counter reaches 1, the watchdog timer flag WDTF is set
logic 1
When the countdown timer counter reaches 1, the countdown timer flag CDTF is set
logic 1
When a minute or second interrupt occurs, the minute/second flag MSF is set logic 1
(see
loading a value in register Watchdg_tim_val
reading of the register Control_2
watchdog
WDTF
INT
Section
Counter reached 1, WDTF is set logic 1, an interrupt is generated.
Specification of t
8.13.1.1)
Rev. 01 — 21 January 2010
TF[1:0]
00
01
10
11
n = 1
w(rst)
t
244 μs
15.625 ms
15.625 ms
15.625 ms
w(rst)
Integrated RTC, TCXO and quartz crystal
PCF2127A
© NXP B.V. 2010. All rights reserved.
MCU
n
001aag062
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