Revision 0:2bbb23558624, committed 2014-10-11

Comitter:

jebradshaw

Date:

Sat Oct 11 06:04:41 2014 +0000

Child:

1:95a90bac5d6d

Commit message:

DS1307 Real Time Clock Library (I2C Interface)

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/DS1307_RTC.cpp	Sat Oct 11 06:04:41 2014 +0000
@@ -0,0 +1,109 @@
+// J Bradshaw
+// 20141010 - I2C Real Time Clock
+
+#include "DS1307_RTC.h"
+
+#define YEAR_OFFSET 2000
+
+DS1307_RTC::DS1307_RTC(PinName sda, PinName scl) : _i2c(sda, scl)
+{
+    _i2c.frequency(400000);
+    
+//    *Day[] = {"","Sun","Mon","Tue","Wed","Thu","Fri","Sat"};
+//    *Mon[] = {"","Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"};
+  
+    Day[0] = "";
+    Day[1] = "Sun";
+       
+    rtc_sec = 0;
+    rtc_minute = 0;
+    rtc_hours = 0;
+    rtc_day = 0;
+    rtc_date = 0;
+    rtc_month = 0;
+    rtc_year = 0;
+}
+
+//function for writing to RTC registers
+void DS1307_RTC::RTC_write_reg(int reg, int val)
+{
+    char cmd[3];
+    cmd[0] = reg;
+    cmd[1] = val & 0xFF;
+    
+    _i2c.write(DS1307_addr, cmd, 2); 
+}
+
+int DS1307_RTC::RTC_read_reg(char reg)
+{
+    char byte_read[2];
+    
+    if(_i2c.write(DS1307_addr, &reg, 1))  //tell the RTC which reg
+        printf("\r\nDS1307 - Error sending address!\0");    
+  
+    if(_i2c.read(DS1307_addr, byte_read, 1))  //read one byte
+        printf("\r\nDS1307 - Error reading!\0"); 
+    return byte_read[0];  
+}
+
+int DS1307_RTC::bcd(int dec)
+{
+    return ((dec/10)<<4) + (dec%10);
+}
+
+int DS1307_RTC::unbcd(int bcd)
+{
+    return ((bcd>>4)*10) + bcd%16;
+}
+
+void DS1307_RTC::set_RTC_time(void)
+{
+    printf("\r\n\r\nSet the Real Time Clock.\r\nEnter Year and press Enter...\r\n");        
+    scanf("%d",&rtc_year);           //Read year
+    RTC_write_reg(6, bcd(rtc_year));    //seconds reg
+    printf("%d\r\n",rtc_year + YEAR_OFFSET); //print year    
+
+    printf("Enter Month and press Enter...\r\n");        
+    scanf("%d",&rtc_month);          //Read month
+    RTC_write_reg(5, bcd(rtc_month));   //month reg
+    printf("%d\r\n",rtc_month);      //print month    
+
+    printf("Enter Day (Sun=1,Mon=2,Tues=3,etc...) and press Enter...\r\n");        
+    scanf("%d",&rtc_day);          //Read day
+    RTC_write_reg(3, bcd(rtc_day));   //day reg
+    printf("%d\r\n",rtc_day);      //print day
+    
+    printf("Enter Date and press Enter...\r\n");        
+    scanf("%d",&rtc_date);          //Read date
+    RTC_write_reg(4, bcd(rtc_date));   //date reg
+    printf("%d\r\n",rtc_date);      //print date
+
+    printf("Enter hours and press Enter...\r\n");        
+    scanf("%d",&rtc_hours);          //Read hour
+    RTC_write_reg(2, bcd(rtc_hours));   //hour reg
+    printf("%d\r\n",rtc_hours);      //print hour
+
+    printf("Enter Minutes and press Enter...\r\n");        
+    scanf("%d",&rtc_minute);          //Read minute
+    RTC_write_reg(1, bcd(rtc_minute));   //minute reg
+    printf("%d\r\n",rtc_minute);      //print minute
+        
+    printf("Enter seconds and press Enter...\r\n");        
+    scanf("%d",&rtc_sec);    //Read sec
+    printf("%d\r\n",rtc_sec); //print sec
+    RTC_write_reg(0, bcd(rtc_sec));     //seconds reg
+}
+
+void DS1307_RTC::get_RTC_time(char *str)
+{   
+    rtc_sec = unbcd(RTC_read_reg(0));    //
+    rtc_minute = unbcd(RTC_read_reg(1));
+    rtc_hours = unbcd(RTC_read_reg(2));
+    rtc_day = unbcd(RTC_read_reg(3));
+    rtc_date = unbcd(RTC_read_reg(4));
+    rtc_month = unbcd(RTC_read_reg(5));
+    rtc_year = unbcd(RTC_read_reg(6)) + YEAR_OFFSET;
+    
+    sprintf(str, "%2d:%02d:%02d %s %s %d %d", rtc_hours,rtc_minute,rtc_sec,Day[rtc_day],Mon[rtc_month], rtc_date, rtc_year);
+    //pc.printf("%s", str);
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/DS1307_RTC.h	Sat Oct 11 06:04:41 2014 +0000
@@ -0,0 +1,38 @@
+
+#ifndef DS1307_RTC_H
+#define DS1307_RTC_H
+
+#include "mbed.h"
+
+#define DS1307_addr 0xd0
+
+#define YEAR_OFFSET 2000
+
+class DS1307_RTC{
+public:
+    DS1307_RTC(PinName sda, PinName scl);
+    
+    void RTC_write_reg(int reg, int val);
+    int RTC_read_reg(char reg);
+    int bcd(int dec);
+    int unbcd(int bcd);
+    void set_RTC_time(void);
+    void get_RTC_time(char *str);        
+
+    char  *Day[];
+    char  *Mon[];
+     
+    int rtc_sec;
+    int rtc_minute;
+    int rtc_hours;
+    int rtc_day;
+    int rtc_date;
+    int rtc_month;
+    int rtc_year;
+    
+private:
+    I2C _i2c;  
+        
+};
+
+#endif /* DS1307_RTC_H */