scalesApp/test_comport_writer/README.md

COM Port Test Writer - Simulates device sending data

This utility simulates a physical device (like scales) by continuously writing test data to a COM port.

Features

• ✅ Writes test data continuously to COM port
• ✅ Multiple data types: scales, counter, random, mixed
• ✅ Configurable write interval
• ✅ Easy start/stop with Ctrl+C
• ✅ List available COM ports
• ✅ Command-line arguments

Setup

1. Install dependencies:

   pip install -r requirements.txt
   

2. Configure environment (optional):

   copy .env.example .env
   # Edit .env with your settings
   

Usage

List Available COM Ports

python test_writer.py --list

Basic Usage (using configured port)

python test_writer.py

Specify COM Port

python test_writer.py --port COM3

Different Data Types

Scales Data (default) - Simulates scale readings

python test_writer.py --type scales

Counter Data - Incrementing numbers

python test_writer.py --type counter

Random Data - Random numeric values

python test_writer.py --type random

Mixed Sensor Data - Temperature, humidity, pressure

python test_writer.py --type mixed

Custom Write Interval

python test_writer.py --interval 2.0  # Send every 2 seconds
python test_writer.py --interval 0.5  # Send every 0.5 seconds

Custom Baud Rate

python test_writer.py --baud 115200

Testing Workflow

1. Start Serial Bridge (reads COM port)

   cd serial_bridge
   python app.py
   

2. Start Test Writer (writes test data)

   cd test_comport_writer
   python test_writer.py --type scales --interval 1.0
   

3. View in React Frontend

   • Open http://localhost:3000
   • Data should appear in real-time

Configuration

Edit .env for default settings:

COM_PORT=COM1
BAUD_RATE=9600
WRITE_INTERVAL=1.0
TEST_DATA_TYPE=scales
SCALES_MIN=0
SCALES_MAX=100

Example Output

==================================================
COM Port Test Writer
==================================================
Port: COM1
Baud Rate: 9600
Data Type: scales
Write Interval: 1.0s
==================================================

✓ Connected to COM1 at 9600 baud
Press Ctrl+C to stop writing data

→ Sent: 45.23 kg
→ Sent: 45.67 kg
→ Sent: 46.12 kg
→ Sent: 46.45 kg
...
(Press Ctrl+C to stop)

✓ Disconnected from COM1
✓ Test writer stopped

Troubleshooting

• "COM port not found": Check COM_PORT setting and ensure port exists
• "Port already in use": Another application is using the port (close Serial Bridge temporarily)
• No data appearing: Ensure Serial Bridge is running and pointing to same COM port
• Baud rate mismatch: Ensure test writer and serial bridge use same baud rate

Complete System Test

To test the complete flow:

# Terminal 1: Django Backend
cd backend
venv\Scripts\activate
python manage.py runserver

# Terminal 2: React Frontend
cd frontend
npm start

# Terminal 3: Serial Bridge
cd serial_bridge
venv\Scripts\activate
python app.py

# Terminal 4: Test Writer
cd test_comport_writer
python test_writer.py --type scales --interval 1.0

Then visit http://localhost:3000 to see real-time data flow.