/* * Maurice Ribble * 4-17-2008 * http://www.glacialwanderer.com/hobbyrobotics * This code tests the DS1307 Real Time clock on the Arduino board. * The ds1307 works in binary coded decimal or BCD. You can look up * bcd in google if you aren't familior with it. There can output * a square wave, but I don't expose that in this code. See the * ds1307 for it's full capabilities. * * Add Wire.begin(); to main setup function when ready to use. * * Modified 9/12/2009 by Arclight for C library use. * arclight@gmail.com */ #include #include DS1307::DS1307(){ } DS1307::~DS1307(){ } // Convert normal decimal numbers to binary coded decimal byte DS1307::decToBcd(byte val) { return ( (val/10*16) + (val%10) ); } // Convert binary coded decimal to normal decimal numbers byte DS1307::bcdToDec(byte val) { return ( (val/16*10) + (val%16) ); } // Stops the DS1307, but it has the side effect of setting seconds to 0 // Probably only want to use this for testing /* void DS1307::stopDs1307() { Wire.beginTransmission(DS1307_I2C_ADDRESS); Wire.write(0); Wire.write(0x80); Wire.endTransmission(); } */ // 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 void DS1307::setDateDs1307(byte second, // 0-59 byte minute, // 0-59 byte hour, // 1-23 byte dayOfWeek, // 1-7 byte dayOfMonth, // 1-28/29/30/31 byte month, // 1-12 byte year) // 0-99 { Wire.beginTransmission(DS1307_I2C_ADDRESS); Wire.write(0); 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 void DS1307::getDateDs1307(byte *second, byte *minute, byte *hour, byte *dayOfWeek, byte *dayOfMonth, byte *month, byte *year) { // Reset the register pointer Wire.beginTransmission(DS1307_I2C_ADDRESS); Wire.write(0); Wire.endTransmission(); Wire.requestFrom(DS1307_I2C_ADDRESS, 7); // A few of these need masks because certain bits are control bits *second = bcdToDec(Wire.read() & 0x7f); *minute = bcdToDec(Wire.read()); *hour = bcdToDec(Wire.read() & 0x3f); // Need to change this if 12 hour am/pm *dayOfWeek = bcdToDec(Wire.read()); *dayOfMonth = bcdToDec(Wire.read()); *month = bcdToDec(Wire.read()); *year = bcdToDec(Wire.read()); } /* // Change these values to what you want to set your clock to. // You probably only want to set your clock once and then remove // the setDateDs1307 call. byte second = 20; byte minute = 9; byte hour = 19; byte dayOfWeek = 6; byte dayOfMonth = 12; byte month = 9; byte year = 9; setDateDs1307(second, minute, hour, dayOfWeek, dayOfMonth, month, year); */