How To Calibrate the RTC For Data Logger Shield
In the video we will look at the following: What is a Real Time Clock?, How to use the Real Time Clock on the data logger shield, the battery backup to keep track of the time even when the power cable is unplugged from the arduino, How to take to the RTC and get the time now, perform a test/calibration of the RTC, Setting the time aka calibrating the time.
NOTE:
If you have an Adafruit Datalogger Shield rev B, you will be using the PCF8523 - this RTC is newer and better than the DS1307. Look on your shield to see if you see PCF8523 written above the chip.
If you have an older Datalogger shield, you will be using the DS1307 - there's no text so you'll just need to remember that if it doesn't say PCF8523 it's the DS1307
You MUST have a coin cell installed for the RTC to work, if there is no coin cell, it will act strangely and possibly hang the Arduino when you try to use it, so ALWAYS make SURE there's a battery installed, even if it's a dead battery.