The recommended crystal oscillator frequency for the DS1302+ is 32.768 kHz.
The time can be set on the DS1302+ by writing the desired time and date values to the corresponding registers (seconds, minutes, hours, day, date, month, and year) using the I2C interface.
The RST (Reset) pin on the DS1302+ is an active-low input that resets the device when pulled low. It can be used to reset the device and restart the oscillator.
Yes, the DS1302+ can be used with a battery backup to maintain the time and date when the main power is lost. The device has a built-in battery switch-over circuit that automatically switches to the battery when the main power is lost.
The operating temperature range of the DS1302+ is -40°C to +85°C.