Ds1307 help (newbie)

Projects General Guidance
1

Hey all. (First post so please be patent)

Im a little stuck on using my ds1307.

Im building a clock, and when certain numbers are displayed i want an action to be performed. By swapping digital pins from low to high.

So if the minute was 27minutes past, turn on this pin, and when its 28 minutes past turn on this pin.........
Ive looked at timealarms however if i use that id need to make an alarm for every minute in the day and that would be a nightmare

Basiclly i need to know if im on the right track by using analog read function? Im very new to this and its my second project thats completly diffrent so my previous limited expirence isnt much help.

Thanks in advance.

2

Using analog read for what?
DS1307 uses I2C for interfacing.
On Uno, that is SCL/SDA pins.

Here's an example sketch that outputs data to the serial port.
Connect RTC to the SCL/SDA pins, use 4.7K pullup resistors to +5V.

/*
Test of RTC DS1307 via I2C.
 Counts 
 Seconds, 
 Minutes, 
 Hours, 
 Date of the Month, 
 Month, 
 Day of the week, and 
 Year with Leap-Year
 
 56 bytes battery backed RAM
 Square Wave Output
 
 11/17/2012- Updated for Wire.write & Wire.read commands
 1/18/13 - fixed unclear reference to 0x00
 */

/*
Modified to Run thru IDE Serial port
*/
#include <Wire.h>

//variables
byte zeroByte = 0;
byte seconds_address = 0x00;
byte seconds; // bit 7 = Clock Halt, Enabled = 0, Halt = 1
// bits 6-5-3 = tens of seconds 0-6,  bits 3-2-1-0 = units of seconds, 0-9

byte minutes_address = 0x01;
byte minutes;  // bits 6-5-4 = tens of minutes, bits 3-2-1-0 = units of minutes

byte hours_address = 0x02; 
byte hours;  // 7=0. 6 = 1 for 12 hr, 0 for 24 hr.
// bit 5: 12 hr mode = AM(0)/PM(1). 24 hr mode = upper tens of hrs
// bit 4 =  lower tens of hrs, bits 3-2-1-0 = units of hours (0-9)

byte day_week_address = 0x03; 
byte day_week = 0; // range 01-07

byte date_month_address = 0x04;
byte date_month = 0; // range 01-31

byte month_address = 0x05;
byte month = 0; // range 01-12

byte year_address = 0x06;
int year = 0; // upper byte 0-9, lower byte 0-9

byte square_address = 0x07;
byte sqwe = 0;  // square wave enable
// Out-0-0-Sqwe-0-0-RS1-RS0
// Out, Sqwe = 0/0 - Square wave output = 0
// Out, Sqwe = 1/0 - Square wave output = 1
// Out, Sqwe = 0/1 or 1/1 - Square wave output per RS1/RS0
// RS1/RS0 = 00 = 1 Hz
// RS1/RSo = 01 = 4 KHz
// RS1/RS0 = 10 = 8 KHz
// RS1/RS0 = 11 = 32 KHz

byte RTC_ram_address = 0x08; //range = 08-63, 0x08-0x3F

int RTC_address = 0x68; // 1101 000 

byte incomingCommand = 0;
byte RTC_write_command = 0;
byte RTC_read_command = 0;
byte RTC_ram_command = 0;

// use F0xx, F1xx,F2xx, F3xx, F4xx, F5xx, F6xx, F7xx
// to send one register write commands
// use E0xx to read registers back - not coded yet
// use C0xx to read RAM back - not coded yet

byte incomingRegister = 0;
byte RTC_register = 0;
byte incomingData1 = 0;
byte incomingData2 = 0;
byte new_data = 0;
byte outgoingData = 0;
int delay_time = 100;

unsigned long currentMillis = 0;
unsigned long previousMillis = 0;
unsigned long duration = 5000;

void setup() {
  Wire.begin(); // no address, we are master
  Serial.begin (57600);  
  Serial.flush();
  currentMillis = millis();  
}

void loop() {

  if (Serial.available() >3){
    incomingCommand = Serial.read();
    incomingRegister = Serial.read();
    incomingData1 = Serial.read();
    incomingData1 = incomingData1 - 0x30; // convert ASCII to HEX
    incomingData2 = Serial.read();
    incomingData2 = incomingData2 - 0x30;  // convert ASCII to HEX
    new_data = (incomingData1 << 4) + incomingData2;  // put the Upper/Lower nibbles together
    Serial.print ("command ");
    Serial.println (incomingCommand);
    Serial.print ("register ");
    Serial.println(incomingRegister);
    Serial.print ("data1 ");
    Serial.println (incomingData1, HEX);
    Serial.print ("data2 ");
    Serial.println (incomingData2, HEX);
    Serial.print ("combined data ");    
    Serial.println (new_data, HEX);
    
  }
  // *******************************************
//  RTC_write_command = incomingCommand & 0xF0;  // mask off high byte
//  if (RTC_write_command == 0xF0){  // check for Write command
if ((incomingCommand == 'F') | (incomingCommand == 'f')){
  incomingCommand = 0;  // reset for next pass
//    RTC_register = incomingCommand & 0x0F;  // mask off low btye
//    incomingCommand = 0;
//    new_data = incomingData;
    Serial.println (" Sending a command ");
//    switch (RTC_register){
switch (incomingRegister){
  case '0': // write seconds
        Serial.println ("Seconds ");
      Wire.beginTransmission(RTC_address); // select device
      Wire.write(seconds_address);          // queue the register
      Wire.write(new_data);                  // queue data
      Wire.endTransmission();            // send it
      delay (delay_time);
      break;
    case '1': // write minutes
    Serial.println ("Minutes ");
      Wire.beginTransmission(RTC_address); // select device
      Wire.write(minutes_address);          // queue the register
      Wire.write(new_data);                  // queue data
      Wire.endTransmission();            // send it
      delay (delay_time);
      break;
    case '2': // write hours
        Serial.println ("Hours ");
      Wire.beginTransmission(RTC_address); // select device
      Wire.write(hours_address);          // queue the register
      Wire.write(new_data);                  // queue data
      Wire.endTransmission();            // send it
     delay (delay_time);
      break;
    case '3': // write day
        Serial.println ("Day ");
      Wire.beginTransmission(RTC_address); // select device
      Wire.write(day_week_address);          // queue the register
      Wire.write(new_data);                  // queue data
      Wire.endTransmission();            // send it
     delay (delay_time);
      break;
    case '4': // write date of month
        Serial.println ("Day of Month ");
      Wire.beginTransmission(RTC_address); // select device
      Wire.write(date_month_address);          // queue the register
      Wire.write(new_data);                  // queue data
      Wire.endTransmission();            // send it
     delay (delay_time);
      break;
    case '5': // write month
        Serial.println ("Month ");
      Wire.beginTransmission(RTC_address); // select device
      Wire.write(month_address);          // queue the register
      Wire.write(new_data);                  // queue data
      Wire.endTransmission();            // send it
     delay (delay_time);
      break;
    case '6': // write year
        Serial.println ("Year ");
      Wire.beginTransmission(RTC_address); // select device
      Wire.write(year_address);          // queue the register
      Wire.write(new_data);                  // queue data
      Wire.endTransmission();            // send it
     delay (delay_time);
      break;
    case '7': // write square wave
        Serial.println ("Square Wave ");
    Serial.println (RTC_register, HEX);
      Wire.beginTransmission(RTC_address); // select device
      Wire.write(square_address);          // queue the register
      Wire.write(new_data);                  // queue data
      Wire.endTransmission();            // send it
     delay (delay_time);
      break;
    case '8': // write RAM
        Serial.print ("RAM ");
    Serial.println (RTC_register, HEX);
      Wire.beginTransmission(RTC_address); // select device
      Wire.write(RTC_ram_address);          // queue the register
      Wire.write(new_data);                  // queue data
      Wire.endTransmission();            // send it
     delay (delay_time);
      break;
      // all others,do nothing
      Serial.println ("Invalid command ");
    }  // end Switch
  } // end if command == 'F'
  // ************************************

  currentMillis = millis();
  if ( (currentMillis - previousMillis) >= duration){
    previousMillis = currentMillis;  
    // Reset the register pointer  
    Wire.beginTransmission(RTC_address);  
    Wire.write(zeroByte);  
    Wire.endTransmission();   

    Wire.requestFrom(RTC_address,8 );  
    seconds = Wire.read();  
    minutes = Wire.read();  
    hours = Wire.read();  
    day_week = Wire.read();  
    date_month = Wire.read();  
    month = Wire.read();  
    year = Wire.read();  
    sqwe = Wire.read();

    // Seconds 
    // bit 7 = Clock Halt, Enabled = 0, Halt = 1
    // bits 6-5-3 = tens of seconds 0-6,  bits 3-2-1-0 = units of seconds, 0-9 

    // Hours
    // 7=0. 6 = 1 for 12 hr, 0 for 24 hr.
    // bit 5: 12 hr mode = AM(0)/PM(1). 24 hr mode = upper tens of hrs
    // bit 4 =  lower tens of hrs, bits 3-2-1-0 = units of hours (0-9)

    Serial.print ("Hrs " );
    Serial.print (hours, HEX);
    Serial.print (" Mins ");
    Serial.print (minutes, HEX);
    Serial.print (" Secs ");
    Serial.print (seconds, HEX);
    Serial.print (" Day ");
    Serial.print (day_week, HEX);
    Serial.print (" Date ");
    Serial.print (date_month, HEX);
    Serial.print (" Month ");
    Serial.print (month, HEX);
    Serial.print (" Year 20");
    Serial.print (year, HEX);
    Serial.print (" Square Wave ");
    Serial.println (sqwe, HEX);

  }
}
3

Hi,

For the other part of your question:

Sshot:
So if the minute was 27minutes past, turn on this pin, and when its 28 minutes past turn on this pin.........
Ive looked at timealarms however if i use that id need to make an alarm for every minute in the day and that would be a nightmare

How many actions are there in total, and how many pins do you need to control? You mention an alarm for every minute of the day, but presumably there's only 60 actions repeating hourly? Perhaps if you can expand on this we'll be able to assist with that too.

And like the DS1307 reading, this is another case where analogRead() isn't the answer, at least with the information we have presently.

Cheers ! Geoff

4

Its to control 28 servos to make a physical 4 digit 7 segment display....

So each segment can flip from black to white to create a number...

Make sence?

So its 28 servos in total... I will use mega finally but im playing with the uno at the moment....

Thanks for your help

5

If you're controlling each physical segment with one pin do you mean solenoids, rather than servos? Do you have a link to the particular actuator you'll be using for each segment?

Your problem itself has reduced in complexity to being one of encoding 1 of 10 patterns (0-9), since the patterns themselves are reused in each digit place. Rather than coding for each minute in a day therefore it's going to be easier to code for converting whatever time is given to you by the clock IC into the right one of those 10 possible patterns repeated for each of 4 digits.

Hope that makes sense. It sounds like a very cool, if potentially noisy, idea for a clock :slight_smile:
Geoff