I solder on spare pcb a pcf8563 acording to diagram:
PCF is connected to I2c 3 (PD_0 and PD_1). Tiva-C is flashed with code:
#include <Wire.h>
#include <RTClib.h>
RTC_PCF8563 RTC;
void setup () {
Serial.begin(57600);
Wire.setModule(3);
Wire.begin();
RTC.begin();
// following line sets the RTC to the date & time this sketch was compiled
RTC.adjust(DateTime(__DATE__, __TIME__));
}
void loop () {
DateTime now = RTC.now();
Serial.print(now.year(), DEC);
Serial.print('/');
Serial.print(now.month(), DEC);
Serial.print('/');
Serial.print(now.day(), DEC);
Serial.print('