PM5 Bluetooth JavaScript Demo

A simple JavaScript implementation for connecting to Concept2 PM5 rowing machines via Web Bluetooth API. This project demonstrates how to:

• Discover and connect to PM5 devices
• Read device information
• Subscribe to real-time workout data
• Parse telemetry data (distance, time, pace, stroke data, etc.)
• Send control commands to the PM5

Features

Device Connection

• Device Discovery: Scan for PM5 devices using Web Bluetooth
• Connection Management: Connect/disconnect with automatic reconnection handling
• Device Information: Read model, serial number, firmware version, etc.

Real-time Data Streaming

• General Status: Elapsed time, distance, workout state, rowing state
• Additional Status: Speed, stroke rate, heart rate, pace
• Stroke Data: Drive length, force, work per stroke, stroke count
• Split Data: Split times, distances, and interval information
• Multiplexed Data: Multiple data types in single notifications

Project Structure

js-pm5/
├── src/
│   ├── constants.js      # PM5 UUIDs and state definitions
│   ├── parsers.js        # Data parsing utilities
│   ├── device.js         # PM5 device class (simplified)
│   └── index.js          # Main demo application
├── index.html            # Demo web interface
├── server.js            # Local development server
├── package.json         # NPM configuration
└── README.md           # This file

Quick Start

Prerequisites

• Modern Browser: Chrome, Edge, or Opera with Web Bluetooth support
• HTTPS: Required for Web Bluetooth (see testing notes below)
• PM5 Device: Concept2 rowing machine or SkiErg with Bluetooth enabled

Installation

1. Install Dependencies:

   cd js-pm5-examples
   npm install

2. Start Development Server:

   npm run dev

3. Open Browser: Navigate to http://localhost:3000

Testing Options

Option 1: Local Development (Limited)

• Use the local server for code development
• Web Bluetooth will be restricted due to HTTP
• Good for testing UI and code structure

Option 2: HTTPS Tunnel (Recommended)

Use ngrok for HTTPS access:

# Install ngrok if you haven't already
npm install -g ngrok

# Start the local server
npm run dev

# In another terminal, create HTTPS tunnel
ngrok http 3000

Then use the HTTPS URL provided by ngrok.

Option 3: Chrome Development Flags

For testing without HTTPS:

# macOS/Linux
google-chrome --enable-web-bluetooth-new-permissions-backend --ignore-certificate-errors

# Windows
chrome.exe --enable-web-bluetooth-new-permissions-backend --ignore-certificate-errors

Usage

Basic Connection Flow

1. Click "Connect to PM5": Browser will show device selection dialog
2. Select Your PM5: Choose your rowing machine from the list
3. Device Information: View device details once connected
4. Start Data Stream: Begin receiving real-time workout data

Real-world Integration

To integrate this code into your app:

import { scanForPM5Devices, PM5Device } from './src/device.js';

// Connect to PM5
const bluetoothDevice = await scanForPM5Devices();
const pm5 = new PM5Device(bluetoothDevice);

// Set up event handlers
pm5.onWorkoutData = (data) => {
    console.log('Workout data:', data);
    // Update your app's UI with workout data
};

pm5.onStrokeData = (data) => {
    console.log('Stroke data:', data);
    // Handle stroke-by-stroke data
};

// Connect and start receiving data
await pm5.connect();
await pm5.startRowingDataNotifications();

Data Types

General Status Data

{
    elapsed_time: 120.50,      // seconds
    distance: 485.2,           // meters
    workout_state: 1,          // see WORKOUT_STATES
    rowing_state: 1,           // see ROWING_STATES
    stroke_state: 2,           // see STROKE_STATES
    drag_factor: 115
}

Additional Status Data

{
    speed: 4.235,              // m/s
    stroke_rate: 24,           // strokes per minute
    heart_rate: 150,           // beats per minute
    current_pace: 125.5,       // seconds per 500m
    average_pace: 128.2        // seconds per 500m
}

Stroke Data

{
    drive_length: 1.25,        // meters
    drive_time: 0.95,          // seconds
    stroke_distance: 8.5,      // meters
    peak_drive_force: 485.2,   // newtons
    average_drive_force: 312.8, // newtons
    work_per_stroke: 285.5,    // joules
    stroke_count: 48
}

Browser Compatibility

Browser	Support	Notes
Chrome 56+	✅ Full	Best support
Edge 79+	✅ Full	Chromium-based
Opera 43+	✅ Full	Chromium-based
Firefox	❌ None	No Web Bluetooth support
Safari	❌ None	No Web Bluetooth support

PM5 Connection States

Workout States

• 0: Waiting to Begin
• 1: Workout Row
• 2: Countdown Pause
• 3: Interval Rest
• 4: Work Time Interval
• 5: End of Workout
• 7: Manual Row

Rowing States

• 0: Inactive
• 1: Active

Stroke States

• 0: Waiting for Wheel to Reach Min Speed
• 1: Waiting for Wheel to Accelerate
• 2: Driving
• 3: Dwelling After Drive
• 4: Recovering

Testing Instructions

With a Real PM5 Device

1. Enable PM5 Bluetooth:

   • Go to Main Menu → More Options → Turn Wireless On
   • PM5 should show "Bluetooth Smart Ready"

2. Start the Demo:

   npm run dev
   # Use ngrok for HTTPS access
   ngrok http 3000

3. Test Connection:

   • Open the ngrok HTTPS URL in Chrome
   • Click "Connect to PM5"
   • Select your PM5 from the list
   • Device info should populate

4. Test Data Streaming:

   • Click "Start Data Stream"
   • Begin rowing on the machine
   • Watch real-time data updates in the browser

Without a PM5 Device

For development without hardware:

1. Code Structure Testing:

   • All modules should load without errors
   • UI should be responsive and functional
   • Button states should update correctly

2. Error Handling:

   • Test with Bluetooth disabled
   • Test connection timeouts
   • Test with unsupported browsers

Troubleshooting

Connection Issues

1. Bluetooth Not Found: Ensure PM5 Bluetooth is enabled
2. No Data: Check that notifications are started
3. Permission Denied: Use HTTPS or Chrome flags

Development Issues

1. Module Errors: Ensure you're using a server (not file://)
2. CORS Errors: Use the provided Express server
3. Import Errors: Check that all files are in correct paths

PM5 Specific

1. Device Not Found: Check PM5 is powered on and Bluetooth enabled
2. Disconnects Frequently: Ensure PM5 firmware is up to date
3. No Workout Data: Start a workout on the PM5 first

Performance Considerations

1. Notification Frequency: PM5 sends data at ~50Hz, consider throttling UI updates
2. Memory Usage: Clear old data regularly for long workouts
3. Battery Impact: Bluetooth notifications consume device battery

Security Notes

• HTTPS Required: Web Bluetooth only works over secure connections
• User Gesture: Connection must be initiated by user interaction
• Permissions: Browser will request permission for each device