DS1302 is a trickle charge clock chip introduced by DALLAS, which contains a real-time clock/calendar and 31 bytes of static RAM, and communicates with the microcontroller through a simple serial interface. The real-time clock/calendar circuit provides information of seconds, minutes, hours, days, weeks, months, and years. The number of days in a month and the number of days in a leap year can be adjusted automatically. Clock operation can be determined by AM/PM indication to adopt 24 or 12 hour format. DS1302 and the single-chip microcomputer can simply use synchronous serial communication, only three ports are needed: (1) RST reset (2) I/O data line (3) SCLK serial clock. The read/write data of the clock/RAM is communicated in one byte or up to 31 byte character groups. The DS1302 has very low power consumption when working, and the power is less than 1mW while maintaining data and clock information

Main performance indicators of DS1302:★ The real-time clock has the ability to calculate seconds, minutes, hours, days, weeks, months, and years before 2100, as well as the ability to adjust leap years★ 31 8-bit temporary data storage RAM★ Serial I/O port mode minimizes the number of pins★ Wide range of working voltage 2.0 5.5V★ When the working current is 2.0V, less than 300nA★ There are two transmission methods when reading/writing clock or RAM data: single-byte transmission and multi-byte transmission character group method★ 8-pin DIP package or optional 8-pin SOIC package according to surface assembly★ Simple 3-wire interface★ Compatible with TTL Vcc=5V★ Optional industrial temperature range -40 +85★ Dual power supply tubes are used for main power supply and backup power supply

The parameters of the DS1302 real-time clock module are as follows:

1. The PCB is a single panel, size: 44mm*23mm*1.6mm

2. With 4 positioning holes, diameter 3.1mm

3. The spare battery is genuine Celestial CR2032, voltage 3V, current 260mAh, non-rechargeable battery. The theoretical data retention time is more than 10 years!

4. Crystal oscillator 32.768KHz, imported from Japan crystal oscillator, matching capacitance 6pF, size 2*6mm

5. DS1302 is a large 8-pin direct-insertion chip made in China. There is an IC socket under the chip, which is convenient for replacing and plugging the chip.

6. The working voltage of the module is compatible with 3.3V/5V and can be connected with 5V and 3.3V single-chip microcomputers

7. Working temperature: 0°---70°

Wiring method (take the provided program as an example, you can connect to any IO port, just modify the port definition in the program):

VCC→+5V/3.3V

GND→GND

CLK→P02

DAT→P01

RST→P00

Precautions:

1. Don't connect VCC and GND reversely, so as not to burn out the chip

2.51 The P0 port of the single-chip microcomputer needs to be connected with a pull-up resistor. If your single-chip microcomputer is not connected with a pull-up resistor, you can connect the data line to other ports

Gallery:

1. LCD1602 clock display in conjunction with our ZS5100 development board (the first line displays the year, month, day and week, and the second line displays the hour, minute, and second)

2. LCD12864 Chinese clock display made in conjunction with our ZS5100 development board: