Datasheet
PCA8565 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet Rev. 4 — 5 December 2014 17 of 48
NXP Semiconductors
PCA8565
Real time clock/calendar
[1] Default value.
8.9 Interrupt output
8.9.1 Bits TF and AF
When an alarm occurs, AF is set to 1. Similarly, at the end of a timer countdown, TF is
set to 1. These bits maintain their value until overwritten by command. If both timer and
alarm interrupts are required in the application, the source of the interrupt is determined
by reading these bits.
Table 26. Register CLKOUT_control (address 0Dh) bits description
Bit Symbol Value Description
7 FE 0 the CLKOUT output is inhibited and CLKOUT output is set
to high-impedance
1
[1]
the CLKOUT output is activated
6 to 2 - - unused
1 to 0 FD[1:0] frequency output at pin CLKOUT
00
[1]
32.768 kHz
01 1.024 kHz
10 32 Hz
11 1 Hz
Example where only the minute alarm is used and no other interrupts are enabled.
Fig 8. AF timing
DDI
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