Modular Flip-Disc Clock

Tip

If you have issues powering the clock, see the list of compatible power adapters.

Specification

• the clock consists of two modules: controller module & flip-disc display module
• two buttons for setting the time
• one button for turning on the clock
• accurate real-time clock (RTC) on board RX8025T
• the RTC clock memory is backed up by a supercapacitor, so the clock does not require an additional battery in the event of a power failure or turn off
• clock dimensions: 53 x 137 x 142mm (2.1" x 5.4" x 5.6")
• power supply from USB-C PD 12V
• ISP programming connector - only for intermediate users

3D Printed Enclosure

You can print your own enclosure or modify the design:

• Download STL files on Printables
• Download the Fusion 360 source file

Datasheet

• CLOCK USER MANUAL
• HOW TO READ THE DISPLAY
• FIRMWARE
• 4x3x3 flip-disc display module v1 - outdated
• 4x3x3 flip-disc display module v2 - current version
• 4x3x3 flip-disc controller module v1 - outdated
• 4x3x3 flip-disc controller module v5 - current version

Programming and Firmware

If you want to modify the firmware, you can program the clock via the ISP connector.

MiniCore Configuration

Before burning the bootloader, install MiniCore using the following Boards Manager URL: https://mcudude.github.io/MiniCore/package_MCUdude_MiniCore_index.json

In Arduino IDE → Tools, configure the settings as follows:

• Board: ATmega328P / ATmega328PA
• Clock: External 12 MHz ⚠
• Bootloader: Yes (UART0)
• BOD: 2.7V
• EEPROM: Retained
• Compiler LTO: Enabled
• Baud Rate: Default
• Variant: 328P / 328PA

⚠ Make sure the clock is set to External 12 MHz. ⚠

Programming Procedure:

1. Select the correct Programmer: AVR ISP MKII (recommended).
2. Click Burn Bootloader to set the fuse bits and configure the microcontroller.
3. After completion, select Upload Using Programmer to flash the firmware.