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STR71X REAL TIME CLOCK APPLICATION EXAMPLE

5.1.4 Code Description

This application note addresses how to convert the 32-bit time value into a date and time value

that can be put in the form of MM/DD/YYYY, HH:MM:SS.

The code should be set up so that:

– The UART0 and HyperTerminal are used to enter a current TIME and DATE after start-up.

– The following hyperterminal configuration is used:

■

- Bits per second ---- > 38 400

- Data bit --------------- > 8

- Parity ----------------- > None

- Stop bits ------------- > 1

- Flow control --------- > None

– After reset, the RTC prescaler is configured to have the RTC counter incremented every sec-

ond.

– Alarm configuration (an alarm is configured after 5s).

– Then enable the RTC alarm interrupt via the EIC configuration.

– A current Date and Time will display on the LCD.

The RTC interrupt service routine:

– Clear the RTC interrupt flag.

– The RTC alarm will be fired after 5 second and the RTC_IRQHandler routine will be execut-

ed. An alarm message will be displayed for 2s and the RTC will be configured to generate

an other alarm interrupt after 5s.

Figure 2 shows the code flow of the algorithm used to convert raw seconds to a date/time.