zihluwang
3382b91c50
- Document features, installation, and usage - Add MIT licence with British English spellings
101 lines
2.4 KiB
Markdown
101 lines
2.4 KiB
Markdown
# Modbus Slave Simulator
|
|
|
|
A configurable Modbus slave simulator for testing Modbus TCP, RTU, and TLS connections.
|
|
|
|
## Features
|
|
|
|
- **Multiple Protocols**: TCP, RTU (serial), and TLS support
|
|
- **Configurable Data Store**: Customisable sizes for coils, discrete inputs, holding registers, and input registers
|
|
- **Initial Values**: Set default values for all data types
|
|
- **Device Identity**: Configurable vendor name, product code, model, and version
|
|
- **Docker Support**: Ready-to-use Docker image
|
|
|
|
## Installation
|
|
|
|
### From Source
|
|
|
|
```bash
|
|
git clone <repository-url>
|
|
cd modbus-slave
|
|
pip install -r requirements.txt
|
|
```
|
|
|
|
### With Docker
|
|
|
|
```bash
|
|
docker pull <username>/modbus-slave
|
|
```
|
|
|
|
## Usage
|
|
|
|
### Command Line
|
|
|
|
```bash
|
|
# TCP server (default: 127.0.0.1:5020)
|
|
python main.py
|
|
|
|
# Custom port
|
|
python main.py --port 5020
|
|
|
|
# RTU mode
|
|
python main.py --type rtu --serial-port /dev/ttyUSB0 --slave-id 2
|
|
|
|
# Custom data store sizes
|
|
python main.py --holding-registers-size 1000 --input-registers-size 500
|
|
|
|
# Set initial values
|
|
python main.py --holding-registers-default 100 --coils-default true
|
|
```
|
|
|
|
### Docker
|
|
|
|
```bash
|
|
# Run with defaults
|
|
docker run -p 5020:5020 <username>/modbus-slave
|
|
|
|
# Run with custom arguments
|
|
docker run -p 5020:5020 <username>/modbus-slave --holding-registers-size 1000
|
|
```
|
|
|
|
## Command Line Options
|
|
|
|
| Option | Description | Default |
|
|
|--------|-------------|---------|
|
|
| `-t, --type` | Server type (tcp, rtu, tls) | tcp |
|
|
| `-h, --host` | TCP bind host | 127.0.0.1 |
|
|
| `-p, --port` | TCP/TLS port | 5020 |
|
|
| `-s, --slave-id` | Modbus slave ID | 1 |
|
|
| `--serial-port` | Serial port (RTU) | /dev/ttyUSB0 |
|
|
| `--baudrate` | Serial baudrate | 9600 |
|
|
| `--coils-size` | Number of coils | 100 |
|
|
| `--holding-registers-size` | Number of holding registers | 100 |
|
|
| `--input-registers-size` | Number of input registers | 100 |
|
|
| `--holding-registers-default` | Default value for holding registers | 0 |
|
|
| `-v, --verbose` | Increase verbosity | - |
|
|
|
|
## Modbus Data Model
|
|
|
|
| Function Code | Data Type | Access |
|
|
|--------------|-----------|--------|
|
|
| 0x01/0x05/0x0F | Coil | Read/Write |
|
|
| 0x02 | Discrete Input | Read Only |
|
|
| 0x03/0x06/0x10 | Holding Register | Read/Write |
|
|
| 0x04 | Input Register | Read Only |
|
|
|
|
## Testing
|
|
|
|
Test with `pymodbus` client:
|
|
|
|
```python
|
|
from pymodbus.client import ModbusTcpClient
|
|
|
|
client = ModbusTcpClient('127.0.0.1', port=5020)
|
|
result = client.read_holding_registers(0, 10)
|
|
print(result.registers)
|
|
client.close()
|
|
```
|
|
|
|
## Licence
|
|
|
|
See [LICENCE](LICENCE) file.
|