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* The PCF2129AT is a CMOS Real Time Clock (RTC) and calendar with an integrated
* Temperature Compensated Crystal Oscillator and a 32.768 kHz quartz crystal
* optimized for very high accuracy and very low power consumption.
*
* This simple example code has been written for the FRDM-KL25Z + OM13513
* boards and demonstrates how to set and read the time/date on the PCF2129AT
* using the SPI (do not forget to remove the JP1 jumper) interface. It also
* illustrates how to use a second interrupt to generate an interrupt on the
* INT pin once per second when the Seconds register increments.
*
* In this example the time to be set is Wednesday, February 26 2020, 10:30 AM.
*
* Connection: FRDM-KL25Z OM13513
* VDD J9-4 P2-2
* GND J9-14 P2-1
* MOSI J2-8 P2-5
* MISO J2-10 P2-6
* SCLK J2-12 P2-4
* CS J2-6 P2-7
* INT J1-6 P2-8
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Enabling the second interrupt by writing 0x01 to the Control_1 register (0x00):
Second interrupt generated on the INT pin once per second:
Setting the time and date by writing to registers Seconds (0x03) - Years (0x09):
Actual time and date shown in the Debug window:
