Creating an Innovative Retro-Fusion Digital Pocket Watch – digiPclock

More than 60 years have passed, and although the glow tubes have been discontinued, many engineers still have a deep affection for them. I created a simulated glow tube clock using 8 LCD screens to appreciate the beauty of retro elements and express my respect for the classic past.

In this smart era, traditional old-fashioned watches have gradually been forgotten. To create a watch that combines digital functionality with a retro appearance, I designed a digital pocket watch called digiPclock (see Figure 1). Compared to traditional wristwatches, pocket watches can easily fit into pockets. To combine this traditional item with modern technology, I added a digital display to the digiPclock, giving its surface a look similar to that of old-fashioned analog clocks.

Figure 1 digiPclock

digiPclock is a powerful digital pocket watch and also a tribute to traditional pocket watches. I hope this unique watch can evoke a sense of nostalgia in people today, in this advanced technological age.

Working Principle

The ESP32-C3搭载 on the digiPclock is the core of the entire project, which has a built-in RTC (real-time clock) that can accurately obtain time information without needing to connect to an external RTC. It can display exquisite analog clocks on the LCD screen, and users can easily set the time through the portal interface. Considering that the entire system is powered by batteries, energy conservation is crucial, so I specifically added a sleep function to effectively reduce power consumption. In addition, the device is also equipped with a convenient USB Type-C interface for easy charging.

Material Introduction

Some materials are shown in Figure 2.

The ESP32-C3 is a controller designed for IoT applications, featuring an ESP32-C3 RISC-V 32-bit single-core processor. It integrates a charging chip TP4057, allowing it to charge the battery via USB Type-C interface.

This display is driven by GC9A01, with a resolution of 240 pixels × 240 pixels and an internal RAM of 129600 words. The LCD supports 12-bit, 16-bit, and 18-bit data buses through the MCU interface, corresponding to RGB444, RGB565, and RGB666 respectively.

I chose a lithium polymer battery with a capacity of 600mAh, using polymer electrolyte instead of liquid electrolyte. This electrolyte is formed by a high conductivity semi-solid (gel) polymer. Compared with other types of lithium batteries, this type can provide higher energy, suitable for mobile devices, remote-controlled aircraft, and electric vehicles.

Creating 3D Models

Tinkercad is a user-friendly online platform. Since it is completely cloud-based, there is no need to install any software, and there are no special system configurations or operating system requirements. I used Tinkercad to create 3D models, with the following printing settings.

● Material: Black ABS.

● Nozzle Diameter: 0.2mm.

● Fill Rate: 40%.

The 3D printed model is shown in Figure 3.

Figure 3 3D Printed Model

Installing Program Libraries

Uploading Program

Download the program from vishalsoniindia’s Github page, unzip the folder, and open the digiPclock.ion file in the Arduino IDE, ensuring that all ESP boards are installed in the Arduino IDE. Connect the ESP32-C3, select the port connected to the circuit board, and click the upload button. Compiling the program may take some time, depending on the system configuration.

After uploading the program to the ESP32-C3, the ESP32-C3 can connect to the circuit, as shown in Figure 4.

Testing and Usage

Press the mode switch button and slide the power switch, and the time setting instructions will be displayed on the screen. After entering the time setting mode, turn on the Wi-Fi on your phone, search for digiPclock and connect, then a webpage will open. Click the set button on the webpage, choose hours and minutes as the time, and then click “Save”. After saving the settings, the hotspot of the digiPclock will turn off, and the pocket watch will display the time.

In time display mode, the pocket watch will display an analog clock on the screen. Press the button on the right side to enter this mode, and release the button to enter sleep mode.

If everything is normal, the screen will turn black in sleep mode. This function was added to save battery life, as the current consumed by the ESP32-C3 is lower in sleep mode, which can extend the device’s runtime.

The bottom of the device is equipped with a USB Type-C interface, which can be charged using a power bank. It takes about 1.5 hours to fully charge, and a full charge can support the device for up to 4 days. Through testing, the current in time display mode is 110mA; in sleep mode, the current is 5.9mA. Therefore, the battery can sustain 4 days of runtime in sleep mode. To reduce power consumption, some modifications to the circuit can be made, which is also my optimization goal for subsequent versions.

Complete Assembly

Conclusion