ITEM NAME:5V DS3234 Timing Clock Module With PIN For Using CR1225 Battery Description: This component is ideally suited to adding a real time clock to your project. DS3234 chipset module, connects directly to your microcontroller through an SPI interface. Module outputs time (seconds/minutes/hours, day/month/year), accessed through libraries supplied on the main site, accomodates for the length of month and leap year. Programmed to have two serperate alarms and change between 24 and 12 hour timing formats. Unfortunately we can only guarantee the calander up to the year 2100. Specification: Demension: 20mm*20mm*10mm Output Type: SPI Battery Type: CR1225 Battery Input Voltage: 5V DC Package Includes: 1 x Clock Module 1 x Clock Pin Note: Using SPI mode to realize the communication, so the corresponding SPI communication interface is connected, and also SCK, MISO, MOSI, CS, then have the module connected to 3.3 V battery. Burn in routine code after connecting the line, open the serial port observation data, you will find time to start timing, and if power off then charging, the time will not be reset, not lost, it will continue timing. SKU: DMO0011849351002642.Battery Type: CR1225 Battery. 1 x Clock Module. Using SPI mode to realize the communication, so the corresponding SPI communication interface is connected, and also SCK, MISO, MOSI, CS, then have the module connected to 3.3 V battery.