DEJA.js

DCC-EX JavaScript Api

The Definitive, Tranformative, Innovative DCC-EX CommandStation API

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This API runs on any supported device with a DCC-EX EX-CommandStation connected via USB. DEJA.js can replace JMRI as a lightweight replacement that runs in modern environments.

What is DEJA.js

• 🧠 NodeJS application that runs on a 💻 Mac/PC/Linux/Raspberry Pi that is connected to a DCC-EX EX-CommandStation
• 🔥 Use 🛰️ DEJA Throttle to connect to DEJA.js and send DCC Loco commands to your track
• 🌎 DEJA.js is written in JavaScript - the most popular programming language in the world^*
• ✨ Replace JMRI. DEJA.js is 🌟 modern, ⚡ blazing fast, it's requirements are simple 🎯, and you'll never look back 👀!

🚀 Getting Started

📦 Prerequisites

• 📦 Install & Configure DCC-EX CommandStation connected via USB to a 💻 Mac/PC/Linux/Raspberry Pi

• 📦 Install NodeJS 20+ on the same 💻 Mac/PC/Linux/Raspberry Pi

  $ nvm install 21

📝 Configure Environment

Create a .env file in this directory.

$ touch .env

Copy & Paste the values below into the.env file.

LAYOUT_ID=[your-layout-name]
VITE_MQTT_BROKER=wss://test.mosquitto.org
VITE_MQTT_PORT=8081
ENABLE_MQTT=true
ENABLE_WS=true
VITE_WS_PORT=8082
VITE_WS_ID=DEJA.js

❗❗❗ 📣 📣 📣 ❗❗❗

Replace your-layout-name with a descriptive name of your layout. Only use lowercase letter, numbers, and dashed. No spaces. No special characters. No emoji.

🤌 GOOD Examples

LAYOUTID=[my-basement-empire]

LAYOUTID=[idaho-crossing]

LAYOUTID=[something-unique]

LAYOUTID=[apple-munchkin-fairy]

💩 BAD Examples

LAYOUTID=[My B@sement "Empire"!]

LAYOUTID=[ID_cross]

LAYOUTID=[my-basement-empire] (already used!)

LAYOUTID=['🍎👶🧚']

🧩 Usage

• 🚀 Install & Run

  Clone this repository and open a terminal in the projet root.

  $ npm i -g pnpm
  $ pnpm install
  $ pnpm run start

• 🛤️ Open a Supported Throttle and connect to the DCC-EX CommandStation via DEJA.js

Command Reference

// TODO: imporove with examples, MQTT Explorer instructions

action	payload	notes
connect	{Object} serial: {String}	Returns: { 'action': 'connected', payload: { path: {String}, baudRate: {String} } }	example: { serial: '/devv/ttyusb2301' }	---
dcc	{String}	send raw DCC command (omit < and >)
getStatus	{Object} { action: 'status', payload: { isConnected: {Boolean} }
listPorts	{Object} { 'action': 'listPorts', [ports] }	Returns array of available USB ports
power	{Integer}	Toggle track power. 1 = ON, 0 = OFF
throttle	{Object} address: {Integer} speed: {Integer}	Forward = positive speed, Reverse = negative -speed
turnout	{Object} turnoutId: {Integer} state: {Boolean}	Toggle DCC-EX Turnout
output	{Object} pin: {Integer} state: {Boolean}	Toggle DCC-EX Output
function	{Object} address: {Integer} function: {Integer} state: {Boolean}	Toggle DCC-EX Locomotive Function

Roadmap

• Convert to TypeScript
• Write Unit Tests
• Support Turnouts
• Support Outputs

🛠️ Built With