DS1307 Lib für Fleury's I2C

[Mos K. (moscito)]

Mahlzeit zusammen,

war in den letzten Tagen vergeblich auf der Suche nach einer DS1307 RTC 
Lib für Peter Fleury's I2C Library.

Also habe ich die Lib von Peteg42 auf "Fleury" umgeschrieben und noch 
ein kleines Schmankerl eingebaut: Man kann nun den RTC auch mit Strings 
auslesen und stellen. Besonders praktisch für LCD und Uart Anwendungen.

Bei mir funzt die Lib einwandfrei.
Da ich kein professioneller Programmierer bin und es sicherlich noch 
genug Platz für Verbesserungen gibt, gibt es die Lib nur "as is".

Verbesserungen sind willkommen, sollten aber bitte vom User selbst 
vorgenommen werden - hab zu wenig Zeit zur Pflege.

Mein kleiner Beitrag zu diesem wundervollen Forum.

Mos Kito

/*
 * DS1307 RTC driver for an ATMEGA328 (really any AVR with TWI hardware).
 *
 * (C)opyright 2010, 2011 Peter Gammie, peteg42 at gmail dot com. All rights reserved.
 * Commenced September 2010.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *i2c_rep_start
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above
 *    copyright notice, this list of conditions and the following
 *    disclaimer in the documentation and/or other materials provided
 *    with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Changed to work with Peter Fleury's I2C Library
 * Added string functions for date and time for easy LCD and UART handling
 * (C)opyright 2011 Mosci.to
 */

#ifndef _ds1307_H_
#define _ds1307_H_

#include <stdbool.h>

#include "i2cmaster.h"
#include <string.h>

/* **************************************** */

/* DS1307-specifics: twi address 0b1101000. Note: shifted left 1. */
#define DS1307_ADDR  0xD0

/* reg0: Turns the clock oscillator on/off. */
#define CLOCK_HALT   7

/* reg7: Square-wave output. */
#define SQW_CONTROL_REG 0x07

#define SQW_OUT         7
#define SQW_SQWE        4
#define SQW_RS1_RS0_1Hz 0x0

/* reg2: if TWELVE_HOUR
 *         then 12hr mode with AMPM indictor,
 *         otherwise 24hr mode. */
#define AMPM         _BV(5)
#define TWELVE_HOUR  _BV(6)

/* Unsigned 8-bit BCD operations. */
#define fromBCD(x) (((x) >> 4) * 10 + ((x) & 0xF))
#define toBCD(x)   ((((x) / 10) << 4) | ((x) % 10))

/* FIXME add bit widths */
struct ds1307_time_t {
  uint8_t seconds;
  uint8_t minutes;
  uint8_t hours;
  uint8_t day;
  uint8_t date;
  uint8_t month;
  uint8_t year;
};

/* **************************************** */

static inline bool ds1307_read(struct ds1307_time_t *time_data)
{
  uint8_t data;

  /* Tell the DS1307 we want to read starting at address 0. */
  i2c_start_wait(DS1307_ADDR+I2C_WRITE);
  i2c_write(0x00);
  /* Commence the read. */
  i2c_rep_start(DS1307_ADDR+I2C_READ);

  data=i2c_readAck();
  time_data->seconds =  fromBCD(data & ~_BV(CLOCK_HALT));

  data=i2c_readAck();
  time_data->minutes = fromBCD(data);

  /* Read the hours register. */
  data=i2c_readAck();
  if(data & TWELVE_HOUR) {
    uint8_t hours = fromBCD(data & 0x1F);
    if(data & AMPM) {
      hours += 12;
    }
    time_data->hours = hours;
  } else {
    time_data->hours = fromBCD(data);
  }

  data=i2c_readAck();
  time_data->day = fromBCD(data);

  data=i2c_readAck();
  time_data->date = fromBCD(data);

  data=i2c_readAck();
  time_data->month = fromBCD(data);

  /* Last read, send NACK. */
  data=i2c_readNak();
  time_data->year = fromBCD(data);

  i2c_stop();
  return true;

}

/* FIXME Assumes the time is sane and is a bit hardwired. */
static inline bool ds1307_write(struct ds1307_time_t *time_data)
{

  /* Tell the DS1307 we want to start writing at address 0. */
  i2c_start_wait(DS1307_ADDR+I2C_WRITE);
  i2c_write(0x00);
  /* Keep the oscillator running. */
  i2c_write(toBCD(time_data->seconds) & ~_BV(CLOCK_HALT));
  i2c_write(toBCD(time_data->minutes));
  /* FIXME 24hr time. */
  i2c_write(toBCD(time_data->hours));
  i2c_write(toBCD(time_data->day));
  i2c_write(toBCD(time_data->date));
  i2c_write(toBCD(time_data->month));
  i2c_write(toBCD(time_data->year));

  i2c_stop();
  return true;

}

/* Initialise the DS11307. Assumes the TWI interface is already initialised. */
static inline bool ds1307_init(bool interrupts)
{
  /* Tell the DS1307 to start the oscillator (turn off CLOCK HALT) in
   * case it has lost power. */
  uint8_t reg0;

  /* Address, say read from memory slot 0, then read data. */
  i2c_start_wait(DS1307_ADDR+I2C_WRITE);
  i2c_write(0x0);
  i2c_rep_start(DS1307_ADDR+I2C_READ);
  reg0=i2c_readNak();

  /* Turn off the clock halt if necessary. */
  if(reg0 & _BV(CLOCK_HALT)) {
    i2c_start_wait(DS1307_ADDR+I2C_WRITE);
    i2c_write(0x0);
    i2c_write(reg0 & ~_BV(CLOCK_HALT));
  }

  /* Fire up the 1Hz interrupt. */
  if(interrupts) {
    i2c_start_wait(DS1307_ADDR+I2C_WRITE);
    i2c_write(SQW_CONTROL_REG);
    i2c_write(_BV(SQW_SQWE) | SQW_RS1_RS0_1Hz);
  }

  i2c_stop();

  return true;

}


void set_time_string(char *time_str2)
{
  /* Function will use a formatted string containing the current time to set RTC clock 
     Format: hh:mm:ss
  */
  
  char time_str1 [3];                                          // Temporary string array
  struct ds1307_time_t t;                                      // Declare structure "t" as a copy of structure ds1307_time_t
  
  ds1307_read(&t);                                            // Read DS1307 and put data in "t struct" so we can write back the date
  memset( time_str1, 0, sizeof( time_str1));                  // Empty the temporary string
  time_str1[0]=time_str2[0];                                  // Copy first character from source string to temporary string
  time_str1[1]=time_str2[1];                                  // Copy second character from source string to temporary string
  t.hours=atoi (time_str1);                                    // Convert temporary string to integer value and store in t structure
  time_str1[0]=time_str2[3];                                  //
  time_str1[1]=time_str2[4];                                  // ... same for the rest of the string
  t.minutes=atoi (time_str1);                                  //
  time_str1[0]=time_str2[6];                                  //
  time_str1[1]=time_str2[7];                                  //
  t.seconds=atoi (time_str1);                                  //
  ds1307_write(&t);                                            // Write structure to RTC

  return;                                                      // Return
}

void set_date_string(char *date_str2)
{
  /* Function will use a formatted string containing the current time to set RTC clock 
     Format: dd.mm.yyyy
  */
  
  char date_str1 [3];                                          // Temporary string array
  struct ds1307_time_t t;                                      // Declare structure "t" as a copy of structure ds1307_time_t
  
  ds1307_read(&t);                                            // Read DS1307 and put data in "t struct" so we can write back the time
  memset( date_str1, 0, sizeof( date_str1));                  // Empty the string
  date_str1[0]=date_str2[0];                                  // Copy first character from source string to temporary string
  date_str1[1]=date_str2[1];                                  // Copy second character from source string to temporary string
  t.date=atoi (date_str1);                                    // Convert temporary string to integer value and store in t structure
  date_str1[0]=date_str2[3];                                  //  
  date_str1[1]=date_str2[4];                                  // ... same for the rest of the string
  t.month=atoi (date_str1);                                    //
  date_str1[0]=date_str2[8];                                  //
  date_str1[1]=date_str2[9];                                  //
  t.year=atoi (date_str1);                                    //
  ds1307_write(&t);                                            // Write structure to RTC

  return;                                                      // Return
}

  
char* get_time_string(void)
{
  /* Function will return a formatted string containing the current time for easy use on LCD and UART 
     Format: hh:mm:ss
  */
  
  char time_str1 [3];                                          // Temporary string array
  static char time_str2 [11];                                  // Needs to be static to survive function exit
  struct ds1307_time_t t;                                      // Declare structure "t" as a copy of structure ds1307_time_t
  
  memset( time_str2, 0, sizeof( time_str2));                  // Empty the string to avoid appending
  
  ds1307_read(&t);                                            // Read DS1307 and put data in "t struct"
  if (t.hours<10) strcat (time_str2,"0");                    // Add leading zero if required
  itoa (t.hours,time_str1,10);                                // Convert hours into ASCII
  strncat (time_str2,time_str1,2);                            // Append hours string to output string
  strcat (time_str2,":");                                      // Append ":"
  if (t.minutes<10) strcat (time_str2,"0");                  // Add leading zero if required
  itoa (t.minutes,time_str1,10);                              // Convert minutes to ASCII
  strncat (time_str2,time_str1,2);                            // Append minutes string to output string
  strcat (time_str2,":");                                      // Append ":"
  if (t.seconds<10) strcat (time_str2,"0");                  // Add leading zero if required
  itoa (t.seconds,time_str1,10);                              // Convert seconds to ASCII
  strncat (time_str2,time_str1,2);                            // Append seconds string to output string

  return time_str2;                                            // Return output string
}


char* get_date_string(void)
{
  /* Function will return a formatted string containing the current date for easy use on LCD and UART 
     Format: dd.mm.yyyy
  */
  
  char date_str1 [3];                                          // Temporary string array
  static char date_str2 [11];                                  // Needs to be static to survive function exit
  struct ds1307_time_t t;                                      // Declare structure "t" as a copy of structure ds1307_time_t
  
  memset( date_str2, 0, sizeof( date_str2));                  // Empty the string to avoid appending
  
  ds1307_read(&t);                                            // Read DS1307 and put data in "t struct"
  if (t.date<10) strcat (date_str2,"0");                      // Add leading zero if required
  itoa (t.date,date_str1,10);                                // Convert date into ASCII
  strncat (date_str2,date_str1,2);                            // Append date string to output string
  strcat (date_str2,".");                                      // Append "."
  if (t.month<10) strcat (date_str2,"0");                    // Add leading zero if required
  itoa (t.month,date_str1,10);                                // Convert month to ASCII
  strncat (date_str2,date_str1,2);                            // Append month string to output string
  strcat (date_str2,".20");                                    // Append ".20"
  if (t.year<10) strcat (date_str2,"0");                      // Add leading zero if required
  itoa (t.year,date_str1,10);                                // Convert year to ASCII
  strncat (date_str2,date_str1,2);                            // Append year string to output string

  return date_str2;                                            // Return output string
}

#endif /* _ds1307_H_ */

[Michael (Gast)]

SUPER!

bin im Moment dabei eine DS1338 am ATMEGA32 zu verwenden.

habe weder mit RTC noch mit I2C gearbeitet bis jetzt. Habe mich aber 
ebenfalls für die PF lib entschieden, da kommt mir deine umgebaute 
rtc-lib gerade recht.

Das einzige was mir bei der PF lib noch fehlt ist eine function zum 
senden und empfangen von mehreren bytes, so dass man ein array z.b. 
"calender" mit allen inhalten auf einmal übertragen kann.

Wenn ich so weit bin werde ich hie rein kleines update von der ein oder 
andren function hier bringen.

Danke schonmal für das posten, hilft mir gut weiter :)

[Jürgen (Gast)]

Hi,

ich habe eine bescheidene Frage bezüglich der Funktionen dieser lib.

Ich möchte lediglich einen Funktionsaufruf von ds1307_read un 
ds1308_write starten. In diesen Funktionen sind ja die Zeiger als 
Parameter drin. Sorry, aber ich konnte nirgends finden wie ich diese 
Funktion aus meiner main loop aufrufe.


static inline bool ds1307_read(struct ds1307_time_t *time_data)
static inline bool ds1307_write(struct ds1307_time_t *time_data)


Die Datentypen sind bei mir ebenfalls das struct von der lib

struct ds1307_time_t {
  uint8_t seconds;
  uint8_t minutes;
  uint8_t hours;
  uint8_t day;
  uint8_t date;
  uint8_t month;
  uint8_t year;
}

Wie also rufe ich folgende funktionen (lesen und schreiben auf) Merci 
für die kleine Unterstützung

[bomba (Gast)]

Hi,

ich habe eine Frage

ich versuche vergeblich diese Funktion get_time_string() aufzurufen und 
auf einem LCD darzustellen. Hat jemand eine idee wie das gehen soll?

Mfg

[Thomas K. (muetze1)]

@Jürgen:

int main(void)
{
  // init TWI
  // init DS1307 (ds1307_init())
 
  ...

  ds1307_time_t lTimeStruct;

  if ( ds1307_read(&lTimeStruct) )
  {
    // mach was mit der Zeit in lTimeStruct
  }
  else
    // Fehler aufgetreten
}

@bomba:

du bekommst einen direkten String zurück, das bedeutet du kannst diesen 
direkt deiner LCD Schreib-Routine übergeben, wenn diese einen char 
Pointer akzeptiert. Aber das hängt vor allem von deiner LCD Bibliothek 
ab - die gibt es schliesslich wie Sand am Meer (wie halt auch 
unterschiedliche Displays & Controller).