Button-bolt-on

Introduction

The Button Bolt-On is a modular accessory designed to enhance the functionality of the ESP32-CAN-X2 development board. It integrates tactile push buttons and RGB LEDs for intuitive user interaction and feedback.

Key Features

Following are the features of 2 main components TS-1002S-04326C and WS2812 (2020 package) that are used in the Button bolt-on board.

Four tactile switches with a 6x6 mm footprint and 4.3 mm actuator height, offering reliable operation and minimal accidental presses.
Eight WS2812B 2020 RGB LEDs are strategically positioned around the buttons to provide clear visual feedback for user actions or system states.

Primary Purpose

Facilitates CAN-based messaging and local device control.
Enhances user experience with interactive lighting and button functions.

Applications

Button bolt-on consists of just a button and an LED so it makes user input functionality simple and efficient. Following are some of the real-world scenarios in which button bolt-ons can fit in perfectly.

Automotive

Driver selection (e.g., using buttons to identify which driver is using the car).
Adjust ECU tuning with a press of a button.

Home Automation

Use buttons to control smart appliances.
Indicate device states with customizable LED lighting patterns.

Industrial Use Cases

Trigger remote devices like pumps or fans.
Use LED signals to display system statuses or warnings

Getting Started

Assembly Instructions

Solder two 20-pin headers SV1 and SV2 to the Button Bolt-on PCB. These headers are available separately from a variety of sources (male/female) Amazon | Ebay
Ensure secure connections between the Bolt-on board and ESP32-CAN-X2 as per the following hardware connection

Hardware Connections

The following are the hardware connections for the Button Bolt-On and the respective ESP32 GPIOs from the ESP32-CAN-X2 board

The Following are the ESP32 GPIOs from the ESP32-CAN-X2 board to be used on the button bolt-on


SV1 Pins	ESP32 GPIO	Purpose
7	GPIO14	Connect to DIN of U1 (WS2812)
8	GPIO21	Connect to Push button S1
9	GPIO47	Connect to Push button S2
10	GPIO48	Connect to Push button S3
14	GPIO38	Connect to Push button S4

Required Tools and Materials

Button Bolt-On board.
ESP32-CAN-X2 development board.
Soldering iron (for assembling headers, if not pre-soldered).
USB cable Type-C for programming the ESP32.

Working

Working of the button bolt-on is simple as mentioned below for both button and LEDs

Each button can be configured to send unique CAN messages when pressed as well as periodically
RGB LEDs can provide dynamic feedback based on:
- Button states (e.g., green for "on," red for "off").
- Incoming CAN messages (e.g., flash when a message is received).
- System diagnostics or statuses.

Project Examples

Project 1: Remote Device Toggle

Description:Use the Bolt-On to send CAN messages to toggle a remote device.

Implementation Steps:

Connect the ESP32-CAN-X2 and button bolt-on on top of each other through the connector SV1 and SV2 in the correct configuration.
Program the ESP32-CAN-X2 board to send a CAN message with the specific data (e.g., "Turn Light On"). based on the button bolt-on input through the S1, S2, S3, and S4 push buttons.
Program the ESP32-CAN-X2 to use the RGB LEDs on the button bolt-on to flash green on successful transmission and red on unsuccessful transmission of the CAN messages.

Project 2: Driver Selection System

Description: Configure buttons to assign driver profiles in a vehicle.

Implementation Steps:

Connect the ESP32-CAN-X2 and button bolt-on on top of each other through the connector SV1 and SV2 in the correct configuration.
Map each button to a driver ID (e.g., Driver A = Button 1).
Use the LEDs to display the selected driver's ID with a specific color pattern.
Button Status / Driver profiles can be sent periodically or on event bases through CAN bus and remotely so some servers as well.

Project 3: Status Indicator

Description: Display system health or warnings using the RGB LEDs.

Implementation Steps:

Connect the ESP32-CAN-X2 and button bolt-on on top of each other through the connector SV1 and SV2 in the correct configuration.
Program the LEDs to show green for normal, yellow for warning, and red for critical conditions.
Update LED states based on incoming CAN messages.
Reset the LED states via buttons as well.

Demo Code

The demo code for the button bolt-on can be found in the following GitHub repo in which the button states are periodically sent over the CAN bus as well as when the button is pressed. Demo Code