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STR71X REAL TIME CLOCK APPLICATION EXAMPLE

Figure 2. C Code Flow:

Here is a section of code taken from main.c which performs the steps shown above in Figure

2 above:

#include "71x_lib.h"

#include "lcd.h"

#include <stdio.h>

#include <time.h>

#include <stdlib.h>

#define RTC_PRESC 0x8000

Adjust current Date and Time

using HyperTerminal and UART0

Use localtime function in order to

convert the current date and time

to seconds since Unix Epoch

Substract this number 0x3FF36300

from the result in order to have

reference date first January 2004

Update the RTC device counter

Use a prescaler value of 0x8000

in order to have the RTC counter

registers incremented every one second

Add this number 0x3FF36300 to the

counter register value in order to have

a start date = 01/01/70

Use mktime function to Convert

the calendar time pointed to by timer

into a broken-down time

Read the RTC counter register value

main

Display time and date

Configure the RTC Alarm

RTC IRQHandler

Clear AIR and GIR Bits

Configure an alarm after 5 seconds

Display an alarm message