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DS1307 can not read and write time in arduino.

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dreamtale

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hello everyone
In mid-November, I have designed a shield based on arduino.I have wrote two posts. https://www.electro-tech-online.com...-back-integrates-a-variety-of-sensors.142927/ and https://www.electro-tech-online.com/threads/arduino-shield-with-magnetometer-clock-and-oled.142780/. have to debug a week.However, it does not work.The OLED display and bluetooth is ok.
Here is my sch
20141202175414.jpg
Here is my pcb
IMG_0492.JPG

You can see in my schematic,I use IIC to connects two devices,they are not wroking properly.First, I tested the DS1307.I found the DS1307 has no answer.
Here is my code base on arduino.
Code:
#include <Wire.h>

int clockAddress = 0x68;  // This is the I2C address
int command = 0;  // This is the command char, in ascii form, sent from the serial port   
long previousMillis = 0;  // will store last time Temp was updated
byte second, minute, hour, dayOfWeek, dayOfMonth, month, year;
byte test;

// Convert normal decimal numbers to binary coded decimal
byte decToBcd(byte val)
{
  return ( (val/10*16) + (val%10) );
}

// Convert binary coded decimal to normal decimal numbers
byte bcdToDec(byte val)
{
  return ( (val/16*10) + (val%16) );
}

// 1) Sets the date and time on the ds1307
// 2) Starts the clock
// 3) Sets hour mode to 24 hour clock
// Assumes you're passing in valid numbers,
// Probably need to put in checks for valid numbers.
void setDateDs1307()              
{
  // Use of (byte) type casting and ascii math to achieve result.
second = (byte) ((Serial.read() - 48) * 10 + (Serial.read() - 48));
  minute = (byte) ((Serial.read() - 48) *10 +  (Serial.read() - 48));
  hour  = (byte) ((Serial.read() - 48) *10 +  (Serial.read() - 48));
  dayOfWeek = (byte) (Serial.read() - 48);
  dayOfMonth = (byte) ((Serial.read() - 48) *10 +  (Serial.read() - 48));
  month = (byte) ((Serial.read() - 48) *10 +  (Serial.read() - 48));
  year= (byte) ((Serial.read() - 48) *10 +  (Serial.read() - 48));
  /*second = 50;
  minute = 56;
  hour  = 9;
  dayOfWeek = 2;
  dayOfMonth = 2;
  month = 12;
  year= 14;*/
  Wire.beginTransmission(clockAddress);
  Wire.write(byte(0x00));
  Wire.write(decToBcd(second));  // 0 to bit 7 starts the clock
  Wire.write(decToBcd(minute));
  Wire.write(decToBcd(hour));    // If you want 12 hour am/pm you need to set
  // bit 6 (also need to change readDateDs1307)
  Wire.write(decToBcd(dayOfWeek));
  Wire.write(decToBcd(dayOfMonth));
  Wire.write(decToBcd(month));
  Wire.write(decToBcd(year));
  Wire.endTransmission();
}


// Gets the date and time from the ds1307 and prints result
void getDateDs1307() {
  // Reset the register pointer
  Wire.beginTransmission(clockAddress);
  Wire.write(byte(0x00));
  Wire.endTransmission();

  Wire.requestFrom(clockAddress, 7);

  // A few of these need masks because certain bits are control bits
  second     = bcdToDec(Wire.read() & 0x7f);
  minute     = bcdToDec(Wire.read());

  // Need to change this if 12 hour am/pm
  hour       = bcdToDec(Wire.read() & 0x3f);
  dayOfWeek  = bcdToDec(Wire.read());
  dayOfMonth = bcdToDec(Wire.read());
  month      = bcdToDec(Wire.read());
  year       = bcdToDec(Wire.read());

  Serial.print(hour, DEC);
  Serial.print(":");
  Serial.print(minute, DEC);
  Serial.print(":");
  Serial.print(second, DEC);
  Serial.print("  ");
  Serial.print(month, DEC);
  Serial.print("/");
  Serial.print(dayOfMonth, DEC);
  Serial.print("/");
  Serial.print(year, DEC);

}


void setup() {
  Wire.begin();
  Serial.begin(57600);
}

void loop() {
  if (Serial.available()) {  // Look for char in serial que and process if found
    command = Serial.read();
    if (command == 84) {      //If command = "T" Set Date
      setDateDs1307();
      getDateDs1307();
      Serial.println(" ");
    }
    else if (command == 81) {  //If command = "Q" RTC1307 Memory Functions
      delay(100);   
      if (Serial.available()) {
        command = Serial.read();
      
        // If command = "1" RTC1307 Initialize Memory - All Data will be set to 255 (0xff).
        // Therefore 255 or 0 will be an invalid value.
        if (command == 49) {
        
          // 255 will be the init value and 0 will be cosidered an error that
          // occurs when the RTC is in Battery mode.
          Wire.beginTransmission(clockAddress);
        
          // Set the register pointer to be just past the date/time registers.
          Wire.write(byte(0x08));
          for (int i = 1; i <= 27; i++) {
            Wire.write(byte(0xff));
            delay(100);
          } 
          Wire.endTransmission();
          getDateDs1307();
          Serial.println(": RTC1307 Initialized Memory");
        }
        else if (command == 50) {      //If command = "2" RTC1307 Memory Dump
          getDateDs1307();
          Serial.println(": RTC 1307 Dump Begin");
          Wire.beginTransmission(clockAddress);
          Wire.write(byte(0x00));
          Wire.endTransmission();
          Wire.requestFrom(clockAddress, 64);
          for (int i = 1; i <= 64; i++) {
            test = Wire.read();
            Serial.print(i);
            Serial.print(":");
            Serial.println(test, DEC);
          }
          Serial.println(" RTC1307 Dump end");
        }
      }
    }
    Serial.print("Command: ");
    Serial.println(command);  // Echo command CHAR in ascii that was sent
  }

  command = 0;  // reset command                
  delay(100);
}

Time is always parked in the 45:85:85,I know this is the wrong data.I use two leonardo to test.Unfortunately, I still did not get the correct data.Then,I suspect that the IIC on my leonardo is broken.
I've used other IIC devices, I put GY-30 connected to leonardo, and the code I‘ve been used,it can't work.I borrowed a Duemilanove from others.The GY-30 can work,and the DS1307 in my shield doesn't work.Now I have no idea.anyone can help me,and anyone can upload code about DS1307 base on arduino,In order to confirm the problem in my code or on my PCB.
Thanks
dreamtale
 
All I can say is make sure that you have the correct pull-ups on the bus and that they are operating at the voltage they are supposed to. Watch for 5 V and 3.3 volt systems.
 
Does the arduino wire library sort out the R/W on the DS1307.... I usually need to address the DS with 0xD0 and set/reset the RW bit manually...
Thank you, I've solved the problem. If no AP2306, DS1307 can work properly.
I'm sure the problem is the level conversion circuit.
 
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