DIY Sports Device with ESP32-C3

Turn on a light?

A doorbell?

Or get people moving?

There are many types of buttons, but my favorite is arcade buttons because they usually have a great feel, that “click” sensation.

I have a few arcade buttons in my toolbox, and I’ve always wanted to do something with them.

One day, I had a bright idea to DIY a sports device using buttons.

I will make 4 sports buttons, one as the main node, with a screen that supports menu display, and the other three as slave nodes, communicating via the ESP-NOW protocol.

They are all based on the ESP32-C3, a microcontroller from DFRobot.

Materials List

• ESP32-C3 x4
• Gravity: I2C OLED-2864 Display
• Gravity: Digital Buzzer Module (Arduino compatible) x4
• 3.7V Battery x4
• WS2812 LED x4
• Arcade Buttons x4
• Power Switch x4
• Enclosure x4

Circuit Connection

• The buzzer connects to pin (6)
• The button wiring connects to pin (5)
• The ws2812 connects to pin (0)
• The screen connects to the I2C interface

This application has 4 nodes, including 1 main node and 3 slave nodes, with the main node having an additional display screen.

Hardware Assembly

Solder the WS2812 LEDs (solder in the order of GND, VCC, signal):

Solder the 3.7V rechargeable lithium battery:

Quickly connect via Gravity interface: Display/Buzzer—ESP32-C3:

Cut out Type-C/display/switch/button cutouts on the plastic enclosure:

Install arcade buttons:

Install the power switch:

Install the display:

Use hot melt glue to secure the battery/buzzer:

Secure the ESP32-C3:

Close the lid and screw it on:

At this point, the main node has been completed, and the above steps need to be repeated to complete the production of the other 3 slave nodes (the slave nodes do not include the display).

Upload Program

This application communicates between master and slave nodes via the ESP-NOW protocol. To communicate via NOW protocol, you need to obtain the unique MAC address of each ESP32-C3, so you know which device to send information to.

Modify the MAC address in the program to your own, and then upload:

Show Gameplay

Briefly talk about the game rules, in the program, I preset three modes, which can be selected by short pressing and confirmed by long pressing for 2 seconds.

When you need to switch, you can always long press to enter the menu.

Mode 1 – Whac-A-Mole Mode

In this mode, a red button will randomly appear on 4 sports buttons, and you need to press it in the shortest time to score.

Mode 2 – Relay Mode

In this mode, every time you press a green button on a sports button, the next sports button will turn green.

Mode 3 – Random Mode

In this mode, when we press the sports button, it will randomly select a sports button. If you don’t know who to choose, let the machine decide for you.

There is also a single node height challenge:

ESP-NOW Delay Test:

To confirm that the NOW protocol can meet communication requirements, a basic ESP-NOW communication delay test was conducted, recording the time it took for a node to send information to another node and receive a return response. The transmission and reception delay is about 4ms, and the one-way propagation delay is about 2ms, which is equivalent to 1/100 seconds.

I guess at this moment you must be sitting, staring at the display screen! After a long time of sitting, how’s your back? Get up and move around, relax a bit!

Portal:<span>https://github.com/DFRobot/SportsButtonESP32C3</span>