1, press button A for 3 second to enter to set hour mode, then press button A for one second to set hour;
2, after setting hour, press button A for 3 second to enter to set minute mode, then press button A for one second to set minute
3, after setting minute, press button A for 3 second to enter to set month mode, then press button A for one second to set month;
4, after setting month, press button A for 3 second to enter to set date mode, then press button A for one second to set date;
5, after setting date, press button A for 3 second to enter to set year mode, then press button A for one second to set year