Datasheet

PCF2129 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet Rev. 7 — 19 December 2014 45 of 86
NXP Semiconductors
PCF2129
Accurate RTC with integrated quartz crystal for industrial applications
8.12.1 Minute and second interrupts
Minute and second interrupts are generated by predefined timers. The timers can be
enabled independently from one another by the bits MI and SI in register Control_1.
However, a minute interrupt enabled on top of a second interrupt cannot be
distinguishable since it occurs at the same time.
The minute/second flag MSF (register Control_2) is set logic 1 when either the seconds or
the minutes counter increments according to the enabled interrupt (see Table 72
). The
MSF flag can be cleared by command.
When SI, MI, WD_CD, AIE, TSIE, BIE, BLIE are all disabled, INT remains high-impedance.
Fig 21. Interrupt block diagram
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