From 7a586e86433e84fde77c58c884eb2c3897951d2f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bart=C5=82omiej=20Przemys=C5=82aw=20Pluta?=
 <noreply.git@mx.bartlomiejpluta.com>
Date: Sun, 8 Nov 2020 10:41:00 +0100
Subject: [PATCH] Create library for PCF8583 (RTC) and enable it

---
 main.c | 13 +++++++++++++
 rtc.c  | 37 +++++++++++++++++++++++++++++++++++++
 rtc.h  | 33 +++++++++++++++++++++++++++++++++
 3 files changed, 83 insertions(+)
 create mode 100644 rtc.c
 create mode 100644 rtc.h

diff --git a/main.c b/main.c
index 42bb0cc..0c1242a 100644
--- a/main.c
+++ b/main.c
@@ -1,13 +1,18 @@
 #include <avr/io.h>
 #include <avr/interrupt.h>
+#include <util/delay.h>
 #include "i2c.h"
+#include "rtc.h"
 #include "led.h"
 
 #define I2C_BITRATE 100000UL // 100kHz
+#define RTC_I2C_ADDR 0xA2
+
 
 int main() 
 {
   i2c_init(I2C_BITRATE); 
+  rtc_int0_init();
   led_init();
 
   sei();
@@ -20,4 +25,12 @@ int main()
   {
 
   }
+}
+
+ISR(INT0_vect)
+{
+  struct time curr_time = rtc_read_time(RTC_I2C_ADDR);
+  led_hour = curr_time.hour;
+  led_minute = curr_time.minute;
+  led_second = curr_time.second;
 }
\ No newline at end of file
diff --git a/rtc.c b/rtc.c
new file mode 100644
index 0000000..77ff5ae
--- /dev/null
+++ b/rtc.c
@@ -0,0 +1,37 @@
+#include <avr/io.h>
+#include "rtc.h"
+#include "i2c.h"
+
+void rtc_int0_init(void)
+{
+  INT0_DIR &= ~(1<<INT0_PIN);
+  INT0_PORT |= (1<<INT0_PIN);
+  GICR |= (1<<INT0);
+}
+
+void rtc_int1_init(void)
+{
+  INT1_DIR &= ~(1<<INT1_PIN);
+  INT1_PORT |= (1<<INT1_PIN);
+  GICR |= (1<<INT1);
+}
+
+void rtc_set_time(uint8_t part, uint8_t value) 
+{  
+  uint8_t bcd = DEC_2_BCD(value);
+  i2c_writebuf(RTC_I2C_ADDR, part, 1, &bcd);
+}
+
+struct time rtc_read_time(void) 
+{
+  uint8_t buffer[3];
+  i2c_readbuf(RTC_I2C_ADDR, 0x02, 3, buffer);
+
+  struct time curr_time = {
+    BCD_2_DEC(buffer[2]),
+    BCD_2_DEC(buffer[1]),
+    BCD_2_DEC(buffer[0])
+  };
+
+  return curr_time;
+}
\ No newline at end of file
diff --git a/rtc.h b/rtc.h
new file mode 100644
index 0000000..9d18ab3
--- /dev/null
+++ b/rtc.h
@@ -0,0 +1,33 @@
+#ifndef __RTC_H__
+#define __RTC_H__
+
+#define RTC_I2C_ADDR 0xA2
+
+#define SECOND 0x02
+#define MINUTE 0x03
+#define HOUR 0x04
+
+#define INT0_PORT PORTD
+#define INT0_DIR DDRD
+#define INT0_PIN PD2
+#define INT1_PORT PORTD
+#define INT1_DIR DDRD
+#define INT1_PIN PD3
+
+
+#define DEC_2_BCD(dec) ((((dec) / 10) << 4) | ((dec) % 10))
+#define BCD_2_DEC(bcd) (((((bcd) >> 4) & 0x0F) * 10) + ((bcd) & 0x0F))
+
+struct time 
+{
+  uint8_t hour;
+  uint8_t minute;
+  uint8_t second;
+};
+
+void rtc_int0_init(void);
+void rtc_int1_init(void);
+void rtc_set_time(uint8_t part, uint8_t value);
+struct time rtc_read_time(void);
+
+#endif
\ No newline at end of file