8. Octopus Real-time Clock

8.1. Introduction

  • OCTOPUS Real-time Clock is a clock module which can achieve counting for year, month, day, hour by using the DS1307 clock chip.


8.2. Characteristics

  • The chip works in a low voltage equipped with 56-byte non-volatile RAM clock calendar

  • It has a complete BCD code real-time clock chip, address and data are passed through two-wire bidirectional serial bus, providing information such as seconds, minutes, hours, etc., and can automatically adjust the number of days per month.

  • It can automatically set the time of the leap year.

  • The chip has built-in power checking circuit that can check the power lost condition and switch the battery.

8.3. Specifications

Item | Parameter :-: | :-: SKU|EF04005 Connector|Two-wire serial interface (IIC Communication) Output|Programmable SQW Detection|Automatic power failure detection and switching circuit Power dissipation|In the standby battery mode, the power consumption is less than 500nA Working temperature|-40℃ ~80℃ Power input|3v-5v Connector type|Digital Pins Definition|1-GND 2-VCC 3-SCK 4-SDA 5-RST

8.4. Quick to Start

Materials used and the connection diagram

  • Connect to IIC port as the picture shows

  • SCL pin needs to connect to SDA pin.

Take sensor:bit for example


Add Package

  • Click “Advanced”in the choice of the MakeCode to find more choices.


  • Click “Extensions”, search “iot”in the dialog box and then download it.



Program as the picture shows

  • Set the number of second as “10” on start to show the second each minute.




You can also download the links below:



  • The current number of second is shown on the micro:bit each minute.

8.5. Relevant Cases

8.6. Technique Files