RTC, real-time clock, provides accurate time reference for electronic systems, especially those without network connection, by using the vibration of crystal oscillator as reference frequency. If the RTC chip works when the main power is cut off, additional battery power is required.
For simple electronic projects, RTC enables more accurate data processing. For example, it is easy to tell when came the sharp changes in temperature, at night? Or at noon. Send the feeding signal every 4 hours from dawn to early night every day, to realize more intelligent pet feeding operation.
RTC Card is based on the DS1307 chip, which supports the I2C protocol. The card requires a Lithium cell battery (CR1225) to operate a long period continuously. The clock operates in either the 24-hour or 12-hour format with AM/PM indicator. The card requires to insert 3V CR1225 lithium cell battery into the battery holder.
Longan Cards is a unique open source development platform designed by Longan Labs. As a plug and play development platform, Longan Cards allows you to quicky build wide array of prototypes and applications in no time. A full set of Arduino libraries and plenty of example codes are available to play with Longan Cards platform.